Fluke 5700a schematic

5700A/5720A Series II

Multi-Function Calibrator

Service Manual

PN 601630 June 1996 Rev. 1, 3/02

LIMITED WARRANTY & LIMITATI O N OF LIABILITY

Each Fluke product is warranted to be free fr om defects in material and workmanship under normal use and service. The warranty period is one year and begins on the date of shipment. Parts, product repairs and services are warranted for 90 days. This warranty extends only to the original buyer or end- user customer of a Fluke authorized reseller, and does not apply to fuses, disposable batt er ies or to any product which, in Fluke’s opinion, has been misused, altered, neglected or damaged by accident or abnormal conditions of operation or handling. Fluke warr ant s t hat software will operate substantially in accordance with its functional specifications for 90 days and that it has been properly recorded on non-defective media. Fluke does not war r ant that software will be error free or operate without interruption.

Fluke authorized resellers shall extend this warranty on new and unused products to end-user customers only but have no authority t o extend a greater or different warr anty on behalf of Fluke. Warranty support is available if product is purchased through a Fluke authorized sales outlet or Buyer has paid the applicable international price. Fluke reserves the right to invoice Buyer for im por tation costs of repair/replacement par t s when product purchased in one country is submitted f or r epair in another country.

Fluke’s warranty obligation is limited, at Fluke’s option, to refund of the purchase pr ice, free of charge repair, or replacem ent of a defective product which is returned to a Fluke authorized service center within the warranty period.

To obtain warranty service, contact your near est Fluke authorized service center or send the product, with a description of the dif ficulty, postage and insurance prepaid (FOB Destination), to the nearest Fluke authorized service center. Fluke assumes no risk for damage in transit. Following warr ant y r epair , the product will be returned to Buyer, transportation prepaid (FO B Dest inat ion) . If Fluke determines that the failur e was caused by misuse, alteration, accident or abnormal condition of operation or handling, Fluke will provide an estimate of repair costs and obt ain aut horization before commencing the work. Following repair, t he pr oduct will be returned to the Buyer transportation prepaid and the Buyer will be billed for t he r epair and return transportation charges (FOB Shipping Point).

THIS WARRANTY IS BUYER’S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU O F ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIM ITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. FLUKE SHALL NOT BE LIABLE FOR ANY SPECI AL, INDIRECT, INCIDENTAL OR CO NSEQUENTIAL DAMAGES OR LOSSES, INCLUDING LOSS OF DATA, W HETHER ARI SING FROM BREACH OF WARRANTY OR BASED ON CONTRACT, TORT, RELI ANCE O R ANY OTHER THEORY.

Since some countries or states do not allow limitat ion of the term of an implied warranty, or exclusion or limitation of incidental or consequential damages, the limitations and exclusions of this warranty may not apply to every buyer . If any provision of this Warranty is held invalid or unenforceable by a court of com petent jurisdiction, such holding will not affect the validity or enfor ceabilit y of any other provision.

Fluke Corporation Fluke Europe B.V. P.O. Box 9090 P.O. Box 1186 Everett, WA 98206-9090 5602 BD Eindhoven U.S.A. The Netherlands

5/94

Interference Information

This equipment generates and uses radio frequency energy and if not installed and used in strict

accordance with the manufacturer’s instructions, may cause interference to radio and television reception. It has been type tested and found to comply with the limits for a Class B computing device in accordance with the specifications of Part 15 of FCC Rules, which are designed to provide reasonable protection against such interference in a residential installation.

Operation is subject to the following two conditions:

This device may not cause harmful interference.

•

This device must accept any interference received, including interference that may cause

•

undesired operation.

There is no guarantee that interference will not occur in a particular installation. If this equipment does cause interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one of more of the following measures:

Reorient the receiving antenna

•

Relocate the equipment with respect to the receiver

•

Move the equipment away from the receiver

•

Plug the equipment into a different outlet so that the computer and receiver are on different

•

branch circuits

If necessary, the user should consult the dealer or an experienced radio/television technician for additional suggestions. The user may find the following booklet prepared by the Federal Communications Commission helpful: How to Identify and Resolve Radio-TV Interference Problems. This booklet is available from the U.S. Government Printing Office, Washington, D.C.

20402. Stock No. 004-000-00345-4.

Declaration of the Manufacturer or Importer

We hereby certify that the Fluke Model 5700A/5720A Series II Calibrator is in compliance with BMPT Vfg 243/1991 and is RFI suppressed. The normal operation of some equipment (e.g. signal generators) may be subject to specific restrictions. Please observe the notices in the users manual. The marketing and sales of the equipment was reported to the Central Office for Telecommunication Permits (BZT). The right to retest this equipment to verify compliance with the regulation was given to the BZT.

Bescheinigung des Herstellers/Importeurs

Hiermit wird bescheinigt, daβ Fluke Models 5700A/5720A Series II Calibrator in Übereinstimung mit den Bestimmungen der BMPT-AmtsblVfg 243/1991 funk-entstört ist. Der vorschriftsmäßige Betrieb mancher Geräte (z.B. Meßsender) kann allerdings gewissen Einschränkungen unterliegen. Beachten Sie deshalb die Hinweise in der Bedienungsanleitung. Dem Bundesamt für Zulassungen in der Telekcommunikation wurde das Inverkehrbringen dieses Gerätes angezeigt und die Berechtigung zur Überprüfung der Seire auf Einhaltung der Bestimmungen eingeräumt.

Fluke Corporation

OPERATOR SAFETY

SUMMARY

WARNING

HIGH VOLTAGE

is used in the operation of this equipment

LETHAL VOLTAGE

may be present on the terminals, observe all safety precautions!

To avoid electrical shock hazard, the operator should not electrically contact the output hi or sense hi binding posts. During operation, lethal voltages of up to 1100V ac or dc may be present on these terminals.

Whenever the nature of the operation permits, keep one hand away from equipment to reduce the hazard of current flowing thought vital organs of the body.

Terms in this Manual

This instrument has been designed and tested in accordance with IEC Publication 348, Safety Requirements for Electronic Measuring Apparatus. This manual contains information and warnings which have to be followed by the user to ensure safe operation and to retain the instrument in safe condition.

Warning statements identify conditions or practices that could result in personal injury or loss of life.

Caution statements identify conditions or practices that could result in damage to the equipment or other property.

Symbols Marked on Equipment

DANGER — High Voltage

Protective ground (earth) terminal

Attention — refer to the manual. This symbol indicates that information about the usage of a feature is contained in the manua

Power Source

The 5700A/5720A Series II is intended to operate from a power source that will not apply more than 264V ac rms between the supply conductors or between either supply conductor and ground. A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation.

Use the Proper Fuse

To avoid fire hazard, use only the fuse specified on the line voltage selection switch label, and which is identical in type voltage rating, and current rating.

Grounding the 5700A/5720A Series II

The 5700A/5720A Series II is Safety Class I (grounded enclosure) instruments as defined in IEC 348. The enclosure is grounded through the grounding conductor of the power cord. To avoid electrical shock, plug the power cord into a properly wired earth grounded receptacle before connecting anything to any of the 5700A/5720A Series II terminals. A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation.

Use the Proper Power Cord

Use only the power cord and connector appropriate for proper operation of a 5700A/5720A Series II in your country.

Use only a power cord that is in good condition. Refer cord and connector changes to qualified service personnel.

Do Not Operate in Explosive Atmospheres

To avoid explosion, do not operate the 5700A/5720A Series II in an atmosphere of explosive gas.

Do Not Remove Cover

To avoid personal injury or death, do not remove the 5700A/5720A Series II cover. Do not operate the 5700A/5720A Series II without the cover properly installed. There are no user-serviceable parts inside the 5700A/5720A Series II, so there is no need for the operator to ever remove the cover.

Do Not Attempt to Operate if Protection May be Impaired

If the 5700A/5720A Series II appears damaged or operates abnormally, protection may be impaired. Do not attempt to operate it. When in doubt, have the instrument serviced.

SERVICING SAFETY

SUMMARY

FOR QUALIFIED SERVICE

PERSONNEL ONLY

Also refer to the preceding Operator Safety Summary

Do Not Service Alone

Do not perform internal service or adjustment of this product unless another person capable of rendering first aid and resuscitation is present.

Use Care When Servicing With Power On

Dangerous voltage exist at many points inside this product. To avoid personal injury, do not touch exposed connections and components while power is on.

Whenever the nature of the operation permits, keep one hand away from equipment to reduce the hazard of current flowing through vital organs of the body.

Do not wear a grounded wrist strap while working on this product. A grounded wrist strap increase the risk of current flowing through the body.

Disconnect power before removing protective panels, soldering, or replacing components.

High voltage may still be present even after disconnecting power.

FIRST AID FOR ELECTRIC SHOCK

Free the Victim From the Live Conductor

Shut off high voltage at once and ground the circuit. If high voltage cannot be turned off quickly, ground the circuit.

If the circuit cannot be broken or grounded, use a board, dry clothing, or other nonconductor to free the victim.

Get Help!

Yell for help. Call an emergency number. Request medical assistance.

Never Accept Ordinary and General Tests for Death

Symptoms of electric shock may include unconsciousness, failure to breathe, absence of pulse, pallor, and stiffness, and severe burns.

Treat the Victim

If the victim is not breathing, begin CPR or mouth-to-mouth resuscitation if you are certified.

Chapter Title Page

1 Introduction and Specifications........................................................ 1-1

1-1. Introduction.......................................................................................... 1-3

1-2. Contacting Fluke .................................................................................. 1-4

1-3. About this Manual................................................................................ 1-4

1-4. How to Use this Manual....................................................................... 1-4

1-5. Additional Instruction Manuals............................................................ 1-5

1-6. Wideband AC Voltage Module (Option 5700A-03)............................ 1-5

1-7. Auxiliary Amplifiers............................................................................ 1-6

1-8. 5725A Amplifier.............................................................................. 1-6

1-9. Support Equipment and Services ......................................................... 1-6

1-10. 732B Direct Voltage Reference Standard........................................ 1-7

1-11. 732B-200 Direct Volt Maintenance Program (U.S.A. Only) .......... 1-7

1-12. 742A Series Resistance Standards................................................... 1-7

1-13. Wideband AC Module (Option 5700A-03) Calibration Support .... 1-7

1-14. Service Centers ................................................................................ 1-8

1-15. The Components of the 5700A/5720A Series II Calibrator................. 1-8

1-16. Calibrating the 5700A/5720A Series II Calibrator............................... 1-9

1-17. The Calibration Process................................................................... 1-10

1-18. Establishing Traceability ................................................................. 1-10

1-19. Calibration Reports.......................................................................... 1-11

1-20. Calibration Check................................................................................. 1-11

1-21. Developing a Performance History...................................................... 1-11

1-22. Range Calibration................................................................................. 1-12

1-23. DC Zeros Calibration ........................................................................... 1-12

1-24. Specifications....................................................................................... 1-12

1-25. Specification Confidence Levels ..................................................... 1-12

1-26. Using Absolute and Relative Uncertainty Specifications................ 1-12

1-27. Using Secondary Performance Specifications................................. 1-13

1-28. DC Voltage Specifications................................................................... 1-14

1-29. AC Voltage Specifications................................................................... 1-17

1-30. Resistance Specifications..................................................................... 1-23

1-31. DC Current Specifications ................................................................... 1-27

1-32. AC Current Specifications ................................................................... 1-30

1-33. Wideband AC Voltage (Option 5700-03) Specifications .................... 1-35

5700A/5720A Series II

Service Manual

2 Theory of Operation........................................................................... 2-1

1-34. General Specifications.......................................................................... 1-36

1-35. Auxiliary Amplifier Specifications...................................................... 1-37

2-1. Introduction.......................................................................................... 2-5

2-2. Calibrator Overview............................................................................. 2-5

2-3. Internal References .......................................................................... 2-5

2-4. Hybrid Reference Amplifiers ...................................................... 2-5

2-5. Fluke Thermal Sensor (FTS)....................................................... 2-5

2-6. Digital-to-Analog Converter (DAC)............................................ 2-6

2-7. Digital Section Overview..................................................................... 2-6

2-8. Analog Section Overview..................................................................... 2-6

2-9. Functional Description Presented by Output Function........................ 2-8

2-10. DC Voltage Functional Description................................................. 2-8

2-11. AC Voltage Functional Description................................................. 2-11

2-12. Wideband AC V Functional Description (Option -03).................... 2-12

2-13. DC Current Functional Description................................................. 2-12

2-14. AC Current Functional Description................................................. 2-12

2-15. Ohms Functional Description.......................................................... 2-13

2-16. System Interconnect Detailed Circuit Description............................... 2-13

2-17. Digital Motherboard Assembly (A4)............................................... 2-13

2-18. Transformer Assembly (A22).......................................................... 2-14

2-19. Analog Motherboard Assembly (A3) .............................................. 2-14

2-20. Front/Rear Binding Posts................................................................. 2-18

2-21. Rear Panel Assembly (A21)............................................................. 2-18

2-22. Filter PA Supply Assembly (A18)................................................... 2-18

2-23. Digital Section Detailed Circuit Description....................................... 2-18

2-24. Digital Power Supply Assembly (A19)............................................ 2-18

2-25. +5V Power Supply....................................................................... 2-19

2-26. ±12V Power Supplies.................................................................. 2-19

2-27. +35V Power Supply..................................................................... 2-19

2-28. +75V Power Supply..................................................................... 2-20

2-29. +35V and +75V Shut-Down Circuit............................................ 2-20

2-30. CPU (Central Processing Unit) Assembly (A20) ............................ 2-21

2-31. Power-Up and Reset Circuit........................................................ 2-21

2-32. Clock Generation......................................................................... 2-21

2-33. Watchdog Timer.......................................................................... 2-24

2-34. Address Decoding and DTACK (Data Acknowledge)................ 2-24

2-35. Interrupt Controller...................................................................... 2-25

2-36. Glue Logic................................................................................... 2-25

2-37. RAM (Random-Access Memory)................................................ 2-25

2-38. ROM (Read-Only Memory) ........................................................ 2-25

2-39. Electrically-Erasable Programmable Read-Only Memory

(EEPROM) .................................................................................. 2-26

2-40. DUART (Dual Universal Asynchronous Receiver/transmitter)

Circuit.......................................................................................... 2-26

2-41. Clock/Calendar Circuit................................................................ 2-26

2-42. Clock Filter Circuit...................................................................... 2-27

2-43. CPU to Rear Panel Interface........................................................ 2-27

2-44. CPU to Front Panel Interface....................................................... 2-27

2-45. Fan Monitor................................................................................. 2-27

2-46. Front Panel Assembly (A2).............................................................. 2-28

2-47. Clock Regeneration Circuitry...................................................... 2-28

2-48. Refresh Failure Detect Circuitry ................................................. 2-28

Contents

2-49. Decoding and Timing Circuitry................................................... 2-28

2-50. Control Display Circuitry............................................................ 2-29

2-51. Output Display Circuitry............................................................. 2-30

2-52. Keyboard Scanner Circuitry........................................................ 2-31

2-53. Knob Encoder Circuitry............................................................... 2-31

2-54. Led Circuitry................................................................................ 2-32

2-55. Keyboard Assembly (A1)................................................................ 2-32

2-56. Analog Section Detailed Circuit Description....................................... 2-33

2-57. Filter/PA Supply (A18), Low-voltage Filter/Regulator Section...... 2-33

2-58. Unregulated OSC Supplies.......................................................... 2-34

2-59. Unregulated LH Supplies ............................................................ 2-34

2-60. Unregulated S Supplies ............................................................... 2-34

2-61. Triac Circuit................................................................................. 2-34

2-62. FR1 Supplies................................................................................ 2-34

2-63. Unregulated FR1 Supply ............................................................. 2-34

2-64. FR2 Supplies................................................................................ 2-35

2-65. Filter/PA Supply (A18), Power Amplifier Output Supply Section . 2-35

2-66. ±PA Supplies Digital Control...................................................... 2-35

2-67. ±250V and ±500V Supplies ........................................................ 2-37

2-68. +PA and -PA Supplies................................................................. 2-37

2-69. ±PA Supply Current Limit........................................................... 2-37

2-70. Regulator/Guard Crossing Assembly (A17).................................... 2-38

2-71. Voltage Regulator Circuitry........................................................ 2-38

2-72. Regulated OSC Supplies.............................................................. 2-38

2-73. Regulated LH Supplies................................................................ 2-39

2-74. Regulated S Supplies................................................................... 2-39

2-75. FR1 Supply.................................................................................. 2-40

2-76. FR2 Supply.................................................................................. 2-40

2-77. Guarded Digital Control Circuitry............................................... 2-41

2-87. Switch Matrix Assembly (A8)......................................................... 2-43

2-88. Switch Matrix Digital Control..................................................... 2-44

2-89. Switch Matrix Operation: 11V DC and 22V DC Ranges............ 2-46

2-90. Switch Matrix Operation: 2.2V AC and 22V AC Ranges........... 2-48

2-91. Switch Matrix Operation: 220V AC and DC Ranges.................. 2-48

2-92. Switch Matrix Operation: 2.2V DC Range ................................. 2-51

2-93. Calibration of the 2.2V Range..................................................... 2-53

2-94. Switch Matrix Operation: 220 mV DC Range ............................ 2-53

2-95. Switch Matrix Operation: 220 mV AC Range ............................ 2-56

2-96. Switch Matrix Operation: 2.2 mV and 22 mV AC Ranges......... 2-56

2-97. Calibration of the mV Ranges..................................................... 2-56

2-98. Internal CAL Zero Amplifier....................................................... 2-59

2-99. Switch Matrix 5725A Amplifier Interface.................................. 2-61

2-100. DAC Assembly (A11)...................................................................... 2-61

2-101. Basic DAC Theory of Operation................................................. 2-61

2-102. DAC Assembly Digital Control................................................... 2-64

2-103. DAC Assembly Reference Circuitry........................................... 2-64

2-104. Duty-Cycle Control Circuit......................................................... 2-65

2-105. DAC Filter Circuit....................................................................... 2-66

2-106. DAC Output Stage....................................................................... 2-66

2-107. Sense Current Cancellation Circuit............................................. 2-67

2-108. Linearity Control Circuit............................................................. 2-67

2-109. Negative Offset Circuit................................................................ 2-68

2-110. DAC Output Switching................................................................ 2-68

2-111. DAC Buffered Reference Sip...................................................... 2-68

2-112. Calibration Hardware .................................................................. 2-69

(continued)

iii

5700A/5720A Series II

Service Manual

2-113. ADC Amplifier............................................................................ 2-69

2-114. ADC Input Selection.................................................................... 2-69

2-115. ADC Circuit................................................................................. 2-70

2-116. How the DAC is Used in Calibration.......................................... 2-72

2-117. DAC Assembly Calibration......................................................... 2-72

2-118. Oscillator Section Overview............................................................ 2-73

2-119. Oscillator Control Assembly (A12)................................................. 2-73

2-120. Oscillator Control Digital Control............................................... 2-74

2-121. Oscillator Input Switching........................................................... 2-74

2-122. Sense Current Cancellation ......................................................... 2-74

2-123. Averaging Converter.................................................................... 2-75

2-124. Error Integrator............................................................................ 2-75

2-125. Three-Pole Filter.......................................................................... 2-75

2-126. Analog Amplitude Control Loop................................................. 2-75

2-127. AC/DC Thermal Transfer Circuit................................................ 2-77

2-128. Oscillator Calibration .................................................................. 2-79

2-129. AC/DC Frequency Response Characterization ........................... 2-80

2-130. Oscillator Output Assembly (A13).................................................. 2-80

2-131. Oscillator Output Digital Control................................................ 2-82

2-132. Quadrature RC Oscillator............................................................ 2-82

2-133. Oscillator Amplitude Control...................................................... 2-83

2-134. Phase−locked Loop...................................................................... 2-83

2-135. 2.2V and 22V Range Output Amplifier....................................... 2-84

2-136. Oscillator Wideband Smd Assembly (A13A1) ........................... 2-84

2-137. Output Stage ................................................................................ 2-85

2-138. Phase Shifter................................................................................ 2-85

2-139. Power Amplifier Assembly (A16)................................................... 2-85

2-140. Power Amplifier Digital Control Sip Assembly (A16A1).......... 2-86

2-141. PA Common Circuitry................................................................. 2-87

2-142. +PA and -PA Supplies................................................................. 2-87

2-143. PA Input Stage............................................................................. 2-87

2-144. PA Mid Stage............................................................................... 2-88

2-145. PA Output Stage.......................................................................... 2-88

2-146. PA Sense Current Cancellation Circuitry.................................... 2-89

2-147. PA in Standby.............................................................................. 2-89

2-148. PA Operation: 220V DC Range .................................................. 2-89

2-149. PA Operation: 220V AC Range .................................................. 2-91

2-150. High Voltage Assembly Support Mode....................................... 2-91

2-153. 220V DC Internal Calibration Network ...................................... 2-92

2-154. PA Calibration............................................................................. 2-92

2-155. High Voltage Assemblies (A14 and A15) ....................................... 2-96

2-156. 1100V AC Range......................................................................... 2-96

2-157. 1100V DC Range......................................................................... 2-98

2-158. HVDC Power Supply Filter Circuit............................................. 2-98

2-159. HV DC Output Series Pass and Current Limit Circuit................ 2-98

2-160. DC HV Amplifier/AC Sense Buffer............................................ 2-100

2-161. 2.2A Range.................................................................................. 2-100

2-162. 2.2A Power Supply Filter Circuit................................................ 2-102

2-163. High Voltage Digital Control...................................................... 2-103

2-164. High Voltage Calibration............................................................. 2-104

2-165. Calibration of the AC Function................................................... 2-104

2-166. Calibration of the Current Function. ........................................... 2-106

2-167. High Voltage Magnitude Control................................................ 2-106

2-168. Ohms Overview ............................................................................... 2-108

Contents

2-169. Ohms Main Assembly (A10)........................................................... 2-109

2-170. Selection of Resistance Values.................................................... 2-109

2-171. Ohms Main Assembly Support of Current Function Calibration 2-112

2-172. Ohms Digital Control .................................................................. 2-112

2-173. Ohms Cal Assembly (A9)................................................................ 2-112

2-174. Ohms CAL Digital Control ......................................................... 2-112

2-175. 1, 1.9, and Short Resistance......................................................... 2-113

2-176. Two-Wire Ohmmeter Compensation Circuit. ............................. 2-113

2-180. Ohms Calibration......................................................................... 2-115

2-186. Current/High Resolution Oscillator Assembly Overview (A7)....... 2-121

2-187. Current Section............................................................................ 2-122

2-199. High-Resolution Oscillator Section............................................. 2-128

2-204. Rear Panel Assembly (A21)............................................................. 2-130

2-205. Rear Panel Power Supplies.......................................................... 2-131

2-206. Rear Panel Address Mapping...................................................... 2-131

2-207. Clock Regeneration Circuit......................................................... 2-132

2-208. IEEE-488 (GPIB) Interface.......................................................... 2-132

2-209. RS-232C Interface....................................................................... 2-132

2-210. Auxiliary Amplifier Interface...................................................... 2-133

2-211. 5725A Interface........................................................................... 2-133

2-212. Phase Lock In/Variable Phase out............................................... 2-133

2-213. Rear Panel Relay Control............................................................ 2-134

2-214. Rear Panel CPU Interface............................................................ 2-134

2-215. Wideband AC Module (Option -03)................................................ 2-135

2-216. Wideband Oscillator Assembly (A6) .......................................... 2-135

2-222. Wideband Output Assembly (A5)............................................... 2-138

(continued)

3 Calibration and Verification .............................................................. 3-1

3-1. Introduction.......................................................................................... 3-3

3-2. Accessing the Fuse............................................................................... 3-4

3-3. Cleaning the Air Filter.......................................................................... 3-5

3-4. Cleaning the Exterior ........................................................................... 3-6

3-5. Calibration............................................................................................ 3-6

3-6. Calibrating the 5700A/5720A Series II to External Standards............ 3-6

3-7. Calibration Requirements ................................................................ 3-7

3-8. When to Adjust the Calibrator’s Uncertainty Specifications .......... 3-7

3-9. Calibration Procedure ...................................................................... 3-8

3-10. Range Calibration................................................................................. 3-14

3-11. Calibrating the Wideband AC Module (Option 5700A-03)................. 3-17

3-12. Performing a Calibration Check........................................................... 3-20

3-13. Full Verification................................................................................... 3-22

3-14. Required Equipment for All Tests................................................... 3-23

3-15. Warm-up Procedure for All Verification Tests ............................... 3-23

3-16. Resistance Verification Test............................................................ 3-25

3-17. Two-Wire Compensation Verification ............................................ 3-27

3-18. DC Voltage Verification Test.......................................................... 3-28

3-19. DC Voltage One-Tenth Scale Linearity Test................................... 3-29

3-20. Direct Current Accuracy Verification Test...................................... 3-30

3-21. AC Voltage Frequency Accuracy Test ............................................ 3-31

3-22. Output Level Tests For AC V Ranges............................................. 3-31

3-23. AC Current Test, 22 mA to 11A Ranges......................................... 3-33

3-24. AC Current Test, 2 mA and 200 µA Ranges ................................... 3-36

3-25. Rationale for Using Metal-Film Resistors to Measure AC Current 3-37

3-26. Wideband Frequency Accuracy Test............................................... 3-38

5700A/5720A Series II

Service Manual

4 Maintenance....................................................................................... 4-1

3-27. Wideband AC Voltage Module Output Verification....................... 3-38

3-28. Wideband Output Accuracy at 1 kHz Test........................................... 3-39

3-29. Wideband Output Flatness Test ........................................................... 3-40

3-30. Wideband Flatness Calibration Procedure....................................... 3-41

3-31. Optional Tests ...................................................................................... 3-42

3-32. DC Voltage Load Regulation Test................................................... 3-42

3-33. DC Voltage Linearity Test............................................................... 3-43

3-34. DC Voltage Output Noise (10 Hz to 10 kHz) Test.......................... 3-43

3-35. DC Voltage Output Noise (0.1 to 10 Hz) Test................................. 3-45

3-36. AC Voltage Distortion Test............................................................. 3-45

3-37. Wideband Distortion Testing........................................................... 3-45

3-38. AC Voltage Overshoot Test............................................................. 3-46

3-39. Minimum Use Requirements................................................................ 3-46

3-40. Determining Test Limits for Other Calibration Intervals..................... 3-48

4-1. Introduction.......................................................................................... 4-3

4-2. Cleaning the Air Filter.......................................................................... 4-3

4-3. General Cleaning.................................................................................. 4-4

4-4. Cleaning PCA’s..................................................................................... 4-4

4-5. Access Procedures................................................................................ 4-4

4-6. Top and Bottom Covers................................................................... 4-4

4-7. Digital Section Cover....................................................................... 4-4

4-8. Analog Section Covers..................................................................... 4-4

4-9. Rear Panel Removal and Installation............................................... 4-4

4-10. Rear Panel Assembly Access........................................................... 4-5

4-11. Front Panel Removal and Installation.............................................. 4-6

4-12. Display Assembly Removal and Installation............................... 4-6

4-13. Keyboard Assembly Removal and Installation ........................... 4-7

4-14. Analog Assembly Removal and Installation.................................... 4-7

4-15. Digital Assembly Removal and Installation .................................... 4-9

4-16. Power Transformer Removal and Installation................................. 4-9

4-17. Hybrid Cover Removal.................................................................... 4-9

4-18. Front/Rear Binding Post Reconfiguration............................................ 4-9

4-19. Installing a Wideband AC Module (Option -03).................................. 4-11

4-20. Clearing Ghost Images from the Control Display................................ 4-11

4-21. Replacing the Clock/Calendar Backup Battery.................................... 4-11

4-22. Using Remote Commands Reserved for Servicing.............................. 4-12

4-23. Using the ETIME Command............................................................ 4-12

5 Troubleshooting................................................................................. 5-1

5-1. Introduction.......................................................................................... 5-3

5-2. Interpreting Diagnostic Fault Codes..................................................... 5-3

5-3. Component-level Troubleshooting....................................................... 5-40

5-4. Troubleshooting the Wideband Output Assembly (A5).................. 5-40

5-5. Troubleshooting the Wideband Oscillator Assembly (A6)............. 5-42

5-6. Troubleshooting the Current/Hi-Res Assembly (A7)...................... 5-47

5-7. Current Section............................................................................ 5-47

5-8. Hi-Res Oscillator Section............................................................ 5-52

5-9. Troubleshooting the Switch Matrix Assembly (A8)........................ 5-54

5-10. Troubleshooting the Ohms Cal Assembly (A9)............................... 5-56

5-11. Two-wire Compensation Circuit................................................. 5-56

5-12. Troubleshooting the Ohms Main Assembly (A10).......................... 5-57

Contents

5-13. Troubleshooting the DAC Assembly (A11).................................... 5-58

5-14. Duty-cycle Control Circuit.......................................................... 5-63

5-15. ADC Circuit................................................................................. 5-67

5-16. Buffered Reference SIP Assembly (A11A2):.............................. 5-68

5-17. Troubleshooting the Oscillator Control Assembly (A12)................ 5-69

5-18. Troubleshooting the Oscillator Output Assembly (A13)................. 5-72

5-19. Troubleshooting the High Voltage Control Assembly (A14).......... 5-74

5-20. Magnitude Control Circuit........................................................... 5-76

5-21. Troubleshooting the High Voltage/High Current Assembly (A15). 5-77

5-22. Troubleshooting the Power Amplifier Assembly (A16).................. 5-79

5-23. Troubleshooting the Filter/PA Supply Assembly (A18) ................. 5-82

6 List of Replaceable Parts .................................................................. 6-1

6-1. Introduction.......................................................................................... 6-3

6-2. How to Obtain Parts............................................................................. 6-3

6-3. Manual Status Information................................................................... 6-3

6-4. Newer Instruments................................................................................ 6-3

6-5. Service Centers..................................................................................... 6-4

7 Schematic Diagrams.......................................................................... 7-1

(continued)

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Service Manual

viii

List of Tables

Table Title Page

1-1. Auxiliary Amplifier Data....................................................................................... 1-6

1-2. 5720A Series II DC Voltage Specifications: 99 % and 95 % Confidence Levels 1-14 1-3. 5700A Series II DC Voltage Specifications: 99 % and 95 % Confidence Levels 1-15 1-4. DC Voltage Secondary Performance Specifications and Operating

Characteristics ....................................................................................................... 1-16

1-5. 5720A Series II AC Voltage Specifications: 99 % Confidence Level.................. 1-17

1-6. 5720A Series II AC Voltage Specifications: 95 % Confidence Level.................. 1-18

1-7. 5700A Series II AC Voltage Specifications: 99 % Confidence Level.................. 1-19

1-8. 5700A Series II AC Voltage Specifications: 95 % Confidence Level.................. 1-20

1-9. AC Voltage Secondary Performance Specifications and Operating

Characteristics ....................................................................................................... 1-21

1-10. 5720A Series II Resistance Specifications: 99 % and 95 % Confidence Levels.. 1-23 1-11. 5700A Series II Resistance Specifications: 99 % and 95 % Confidence Levels.. 1-24 1-12. Resistance Secondary Performance Specifications and Operating

Characteristics ....................................................................................................... 1-25

1-13. Current Derating Factors....................................................................................... 1-26

1-14. 5720A Series II DC Current Specifications: 99 % and 95 % Confidence Levels. 1-27 1-15. 5700A Series II DC Current Specifications: 99 % and 95 % Confidence Levels. 1-28 1-16. DC Current Secondary Performance Specifications and Operating

Characteristics ....................................................................................................... 1-29

1-17. 5720A Series II AC Current Specifications: 99 % Confidence Level .................. 1-30

1-18. 5720A Series II AC Current Specifications: 95 % Confidence Level .................. 1-31

1-19. 5700A Series II AC Current Specifications: 99 % Confidence Level .................. 1-32

1-20. 5700A Series II AC Current Specifications: 95 % Confidence Level .................. 1-33

1-21. AC Current Secondary Performance Specifications and Operating

Characteristics ....................................................................................................... 1-34

1-22. Wideband AC Voltage (Option 5700-03) Specifications...................................... 1-35

2-1. Analog Motherboard Connectors .......................................................................... 2-17

2-2. Supplies Generated by the Digital Power Supply ................................................. 2-19

2-3. CPU Acronym Glossary ........................................................................................ 2-23

2-4. CPU Memory Map ................................................................................................ 2-24

2-5. CPU Interrupts, Priorities, and Vectors................................................................. 2-25

5700A/5720A Series II

Service Manual

2-6. Front Panel Memory Map...................................................................................... 2-29

2-7. Control Lines for the Keyboard LEDs................................................................... 2-32

2-8. Unregulated Supplies from the Filter Assembly................................................... 2-33

2-9. Regulated Supplies from the Filter/PA Supply..................................................... 2-33

2-10. Regulated Outputs from the Regulator/Guard Crossing Assembly ...................... 2-39

2-11. Inguard CPU Memory Map................................................................................... 2-41

2-12. Inguard CPU Interrupts.......................................................................................... 2-43

2-13. PA and -PA Supply Settings at Different Outputs ................................................ 2-87

2-14. AC and DC Current Ranges................................................................................... 2-122

2-15. Relay Settings for Current Range Selection.......................................................... 2-125

2-16. Divider Settings and VCO Frequencies................................................................. 2-131

3-1. Standards for Calibrating 5700A/5720A Series II................................................ 3-7

3-2. List of Required Equipment for Main Output....................................................... 3-24

3-3. Equipment Required for Resistance Testing......................................................... 3-25

3-4. Low Value Resistance Calibration Using a Current Source.................................. 3-27

3-5. Equipment Required for DC Voltage Testing....................................................... 3-28

3-6. Equipment Required for Direct Current Test........................................................ 3-30

3-7. Equipment Required for AC V Output Level Tests.............................................. 3-31

3-8. 5790A Adjustment Counts .................................................................................... 3-33

3-9. Equipment Required for 22 mA to 11A Alternating Current Test Using

the 5790A Input 1.................................................................................................. 3-33

3-10. Equipment Required for Alternating Current Accuracy Test for the 2 mA

and 200 uA Ranges................................................................................................ 3-36

3-11. Equipment Required for Testing and Calibrating the Wideband Option.............. 3-39

3-12. Wideband Adjustment Tolerance.......................................................................... 3-40

3-13. Equipment Required For DC V Optional Tests..................................................... 3-42

3-14. Equipment Required for Distortion Test............................................................... 3-45

3-15. Minimum Use Requirements................................................................................. 3-47

3-16. 5720A Resistance Test Record.............................................................................. 3-50

3-17. 5700A Resistance Test Record.............................................................................. 3-52

3-18. DC Voltage Test Record for 5720A...................................................................... 3-54

3-19. DC Voltage Test Record for 5700A...................................................................... 3-55

3-20. Direct Current Accuracy Test Record (5720A)..................................................... 3-56

3-21. Direct Current Accuracy Test Record (5700A)..................................................... 3-57

3-22. AC Voltage Frequency Accuracy Test Record ..................................................... 3-57

3-23. 5720A AC Voltage Output Test Record................................................................ 3-58

3-24. 5700A AC Voltage Output Test Record................................................................ 3-60

3-25. AC Voltage 2 mV Range Test Record .................................................................. 3-61

3-26. 5720A AC Current 20 mA to 10A Accuracy Test Record.................................... 3-62

3-27. 5700A AC Current 20 mA to 10A Accuracy Test Record.................................... 3-63

3-28. 5720A AC Current 2 mA and 200 mA Accuracy Test Record............................. 3-64

3-29. 5700A AC Current 2 mA and 200µA Accuracy Test Record............................... 3-64

3-30. Wideband Frequency Accuracy Testi Record....................................................... 3-65

3-31. Wideband Accuracy at 1 kHz Test Record............................................................ 3-66

3-32. Wideband Flatness Test Record............................................................................ 3-66

3-33. Wideband Absolute Error 10 Hz to 500 kHz......................................................... 3-68

3-34. Load Regulation Test Record................................................................................ 3-69

3-35. DC Voltage Linearity Test Record....................................................................... 3-69

3-36. DC Voltage Output Noise Test.............................................................................. 3-69

3-37. AC V Distortion Test Summary............................................................................ 3-70

Contents

3-38. Test Record for Flatness Check of the AC 2 mV Range....................................... 3-70

5-1. Verifying Multiplexer U 6..................................................................................... 5-46

5-2. Ohms Main Resistance Tolerance ......................................................................... 5-58

6-1. Front Panel Final Assembly .................................................................................. 6-5

6-2. A1 Keyboard PCA................................................................................................. 6-12

6-3. A2 Front Panel PCA.............................................................................................. 6-14

6-4. A3 Analog Motherboard PCA............................................................................... 6-17

6-5. A4 Digital Motherboard PCA................................................................................ 6-19

6-6. A5 Wideband Output PCA, Option -03................................................................ 6-21

6-7. A6 Wideband Ocillator PCA, Option -03.............................................................. 6-25

6-8. A7 Current/High-Res Oscillator PCA................................................................... 6-29

6-9. A8 Switch Matrix PCA.......................................................................................... 6-33

6-10. A9 Ohms Cal PCA................................................................................................. 6-36

6-11. A10 Ohms Main PCA............................................................................................ 6-39

6-12. A11 DAC PCA ...................................................................................................... 6-41

6-13. A11A1 DAC Filter SIP PCA................................................................................. 6-46

6-14. A11A2 DAC Buffered Reference SIP PCA.......................................................... 6-48

6-15. A12 Oscillator Control PCA.................................................................................. 6-50

6-16. A13 Oscillator Output PCA................................................................................... 6-54

6-17. A13A1 Oscillator Wideband SMD PCA.............................................................. 6-58

6-18. A14 High Voltage Control PCA............................................................................ 6-60

6-19. A15 High Voltage/High Current PCA................................................................... 6-63

6-20. A16 Power Amplifier PCA.................................................................................... 6-66

6-21. A16A1 Power Amplifier Digital Control SIP PCA............................................... 6-70

6-22. A17 Regulator/Guard Crossing PCA..................................................................... 6-72

6-23. A18 Filter/PA Supply PCA ................................................................................... 6-75

6-24. A19 Digital Power Supply PCA............................................................................ 6-79

6-25. A20 CPU PCA....................................................................................................... 6-82

6-26. A20 CPU PCA....................................................................................................... 6-83

6-27. A21 Rear Panel PCA............................................................................................. 6-85

(continued)

5700A/5720A Series II

Service Manual

xii

List of Figures

Figure Title Page

1-1. Time and Costs: Calibrator Calibration................................................................. 1-10

1-2. Volt-Hertz Capability ............................................................................................ 1-22

2-1. Digital Section Block Diagram.............................................................................. 2-7

2-2. Analog Section Block Diagram, Part .................................................................... 2-9

2-3. Analog Section Block Diagram, Part .................................................................... 2-10

2-4. System Interconnections........................................................................................ 2-15

2-5. CPU Assembly Block Diagram............................................................................. 2-22

2-6. Power Amplifier Output Supply Simplified Schematic ........................................ 2-36

2-7. Switch Matrix Assembly Simplified Schematic.................................................... 2-45

2-8. Switch Matrix Configuration for 11V DC and 22V DC Ranges........................... 2-47

2-9. Switch Matrix Configuration for 2.2V and 22V AC Ranges ................................ 2-50

2-10. Switch Matrix Configuration for 220V DC and AC Ranges................................. 2-50

2-11. Switch Matrix Configuration for 2.2V DC Range ................................................ 2-52

2-12. Calibration of the 2.2V DC Range ........................................................................ 2-54

2-13. Switch Matrix Configuration for 220 mV DC Range ........................................... 2-56

2-14. V AC, 2.2 mV AC, and 22 mV AC Range............................................................ 2-57

2-15. Divider Calibration................................................................................................ 2-58

2-16. Divider Gain Calibration ....................................................................................... 2-60

2-17. DAC Assembly Simplified Schematic.................................................................. 2-63

2-18. ADC Circuit Measurement Functions................................................................... 2-71

2-19. Oscillator Control Analog Control Loop............................................................... 2-76

2-20. AC/DC Thermal Transfer Circuit.......................................................................... 2-78

2-21. Quadrature RC Oscillator Circuit.......................................................................... 2-81

2-22. Power Amplifier Simplified Schematic................................................................. 2-90

2-23. Power Amplifier DC Calibration Network............................................................ 2-93

2-24. Power Amplifier Calibration AC Attenuator......................................................... 2-95

2-25. High Voltage/High Current Assembly 1100V AC Range..................................... 2-97

2-26. High Voltage/High Current Assembly 1100V DC Range..................................... 2-99

2-27. High Voltage/High Current Assembly 2.2A AC and DC Ranges......................... 2-102

2-28. High Voltage/High Current Assembly Calibration............................................... 2-106

2-29. High Voltage/High Current Assembly 2.2A Range Calibration........................... 2-107

2-30. Ohms Assemblies Simplified Schematic............................................................... 2-111

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Service Manual

2-31. Ohms Main Assembly Simplified Schematic........................................................ 2-111

2-32. Two-Wire Lead Drop Compensatin Circuit.......................................................... 2-114

2-33. Calibration to an External 10 kΩ Standard ........................................................... 2-116

2-34. Ratio Calibration, 10Ω From 100Ω....................................................................... 2-120

2-35. Current Output Simplified Schematic ................................................................... 2-123

2-36. Current Assembly Calibration............................................................................... 2-128

2-37. Wideband Output Assembly Simplified Schematic.............................................. 2-139

3-1. Accessing the Fuse................................................................................................ 3-4

3-2. Accessing the Air Filter......................................................................................... 3-5

3-3. 732B External Calibration Connections................................................................ 3-9

3-4. 742A-1 and 742A-10k External Calibration Connections .................................... 3-12

3-5. 220V DC Range Calibration Connections............................................................. 3-17

3-6. Wideband Module Calibration Connection........................................................... 3-19

3-7. Overview of Verification Tests............................................................................. 3-22

3-8. 1 Ohm and 10 Ohm Resistor Verification............................................................. 3-26

3-9. Direct Current Accuracy Test Setup...................................................................... 3-30

3-10. 1 MHz Low Pass Filter.......................................................................................... 3-31

3-11. AC Voltage Test Setup.......................................................................................... 3-32

3-12. Alternating Current Test Setup.............................................................................. 3-35

3-13. Alternating Current Test Setup2 mA and 200 µA................................................. 3-36

3-14. Metal Film Resistor Equivalent Circuit................................................................. 3-37

3-15. Metal Film Resistor in Test Circuit....................................................................... 3-37

3-16. Wideband Accuracy at 1 kHz Test Setup.............................................................. 3-39

3-17. Wideband Flatness Test Setup............................................................................... 3-40

3-18. DC Voltage Linearity Test..................................................................................... 3-43

3-19. DC Voltage Output Noise Test Setup.................................................................... 3-44

3-20. Determining Other Test Limits.............................................................................. 3-49

4-1. Air Filter ................................................................................................................ 4-3

4-2. Rear Panel Removal .............................................................................................. 4-5

4-3. Rear Panel Assembly Access................................................................................. 4-5

4-4. Front Panel Removal ............................................................................................. 4-6

4-5. Analog and Digital Assemblies ............................................................................. 4-8

5-1. Waveform at TP10................................................................................................. 5-42

5-2. Waveform at TP1................................................................................................... 5-43

5-3. Waveform at TP15................................................................................................. 5-44

5-4. Waveform at Pins 14 and 15 of U1 ....................................................................... 5-45

5-5. Waveform at Pin 6 of U9....................................................................................... 5-46

5-6. Waveform at Pin 11 of K2..................................................................................... 5-48

5-7. Waveform at Pin 6 of K2....................................................................................... 5-49

5-8. Verifying the 220 uA Range of the 220 µA/2.2 mA Amp Circuit........................ 5-49

5-9. Verifying the 2.2 mA Range of the 220 µA/2.2 mA Amp Circuit........................ 5-50

5-10. Verifying the 22 mA Range of the 22 mA/220 mA Amp Circuit......................... 5-50

5-11. Verifying the 220 mA Range of the 22 mA/220 mA Amp Circuit....................... 5-51

5-12. Waveform at Pin 4 of U13..................................................................................... 5-52

5-13. Waveform at TP12................................................................................................. 5-53

5-14. Waveform at TP13................................................................................................. 5-54

5-15. Waveform at TP16................................................................................................. 5-55

5-16. Waveform at Pin 13 of U6..................................................................................... 5-57

5-17. Waveform at TP6................................................................................................... 5-59

xiv

Contents

5-18. Waveform at TP4, Calibrator Set to 0V................................................................ 5-59

5-19. Waveform at TP4, Calibrator Set to 6.5V............................................................. 5-60

5-20. Waveform at TP7................................................................................................... 5-61

5-21. Waveform at TP5................................................................................................... 5-62

5-22. Waveform at Pin 10 of U6..................................................................................... 5-64

5-23. Waveform at Pin 6 of U13..................................................................................... 5-65

5-24. Waveform at Pin 4 of U10..................................................................................... 5-65

5-25. Waveform at TP6................................................................................................... 5-66

5-26. Waveform at Pin 7 of U12..................................................................................... 5-67

5-27. Waveform at Anode of CR4.................................................................................. 5-70

5-28. Waveform at Pin 6 of U11..................................................................................... 5-70

5-29. DC Sense Buffer Waveform TP6.......................................................................... 5-71

5-30. AC Sense Buffer Waveform at TP6 ...................................................................... 5-72

5-31. Waveform at TP 3.................................................................................................. 5-75

5-32. Waveform at Pin 18 of Hybrid H4 ........................................................................ 5-79

5-33. Power Amplifier with Calibrator Set to 22V at 1 kHz.......................................... 5-80

6-1. Front Panel Final Assembly .................................................................................. 6-6

6-2. Chassis Final Assembly......................................................................................... 6-8

6-3. Rear Panel Final Assembly................................................................................... 6-11

6-4. A1 Keyboard PCA................................................................................................. 6-13

6-5. A2 Front Panel PCA.............................................................................................. 6-16

6-6. A3 Analog Motherboard PCA............................................................................... 6-18

6-7. A4 Digital Motherboard PCA................................................................................ 6-20

6-8. A5 Wideband Output PCA, Option -03................................................................. 6-24

6-9. A6 Wideband Oscillator PCA, Option -03............................................................ 6-28

6-10. A7 Current/HIgh-Res Oscillator PCA................................................................... 6-32

6-11. A8 Switch Matrix PCA.......................................................................................... 6-35

6-12. A9 Ohms Cal PCA................................................................................................. 6-38

6-13. A10 Ohms Main PCA............................................................................................ 6-40

6-14. A11 DAC PCA ...................................................................................................... 6-45

6-15. A11A1 DAC Filter SIP PCA................................................................................. 6-47

6-16. A11A2 DAC Buffered Reference SIP PCA.......................................................... 6-49

6-17. A12 Oscillator Control PCA.................................................................................. 6-53

6-18. A13 Oscillator Output PCA................................................................................... 6-57

6-19. A13A1 Oscillator Wideband SMD PCA.............................................................. 6-59

6-20. A14 High Voltage Control PCA............................................................................ 6-62

6-21. A15 High Voltage/High Current PCA................................................................... 6-65

6-22. A16 Power Amplifier PCA.................................................................................... 6-69

6-23. A16A1 Power Amplifier Digital Control SIP PCA............................................... 6-71

6-24. A17 Regulator/Guard Crossing PCA..................................................................... 6-74

6-25. A18 Filter/PA Supply PCA ................................................................................... 6-78

6-26. A19 Digital Power Supply PCA............................................................................ 6-81

6-27. A20 CPU PCA....................................................................................................... 6-84

6-28. A21 Rear Panel PCA............................................................................................. 6-87

(continued)

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Service Manual

xvi

Chapter 1

Introduction and Specifications

Title Page