Linear Technology LTC4232, LTC4232-1 Demo Manual

Page 1

DEMO MANUAL DC1886B

LTC4232 and LTC4232-1:

DESCRIPTION

Demonstration circuit 1886B features the LTC4232 and the LTC4232-1 5A integrated Hot Swap™ controllers. The LTC4232 is ideally suited for demanding power distribution control in 2.9V to 15V applications for hot board insertion protection, high side power switching, and electronic circuit breaker functions. The LTC4232 provides a rich set of features to support Hot Swap applications including:

• 2% accurate undervoltage and over voltage comparators

• Thermal protection

• Adjustable inrush current control

• Adjustable, 10% accurate current limit with programmable cutout time

• Foldback current limiting

• Programmable output voltage ramp rate

• Configurable auto-retry or latchoff on overcurrent faults

• Power good and fault outputs

5A Integrated

Hot Swap Controller

The LTC4232 debounce time is 100ms, while the LTC4232-1 is 16ms. Both are available in a 16-lead 5mm × 3mm DFN package. The LTC4232 is showcased on demonstration circuit 1886B-A. The LTC4232-1 is installed on DC1886B-B. Both demo boards are configured for 12V application. By changing a few passive components, 2.9V to 15V applications can be easily evaluated.

The LTC4232 has limited output voltage slew rate with a typical value of 300V/s, while the LTC4232-1 does not have a special circuit to limit this parameter. The natural (maximum) gate voltage slew rate (SN) of the LTC4232-1 is defined by the internal MOSFET C capacitance) value and gate driver current capability. It is 48000V/s as a typical value.

Design files for this circuit board are available at

http://www.linear.com/demo/DC1886B

L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners.

(reverse transfer

RSS

• Debounce time during supply turn-on

PERFORMANCE SUMMARY

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

/dt GATE Pin Turn-On Ramp Rate LTC4232

GATE

LIM(TH)

UV(RTH)

FB(HYST)

D(AUTO-RETRY)

ADJUST

Board Input Supply Range Min Is UV, Max Is OV 9.2 12 15.1 V

MOSFET + Sense Resistor On-Resistance 15 33 50 mΩ

Current Limit Threshold VFB = 1.23V, No R

OV, UV, FB Pin Threshold Voltage VIN Rising 1.21 1.235 1.26 V

UV Pin Reset Threshold Voltage VUV Falling 0.55 0.62 0.7 V

FB Pin Power Good Hysteresis 10 20 30 mV

Auto-Retry Turn-On Delay (Internal) LTC4232

Timer Period for ADJUSTABLE Option LTC4232

(TA = 25°C)

LTC4232-1 with 10nF GATE Capacitor

SET

= 20k

VFB = 0V VFB = 1.23V, R

LTC4232-1

0.15

1.7

5.0

1.2

2.6

9.5

0.95

0.3

2.4

5.6

1.5

2.9

100

12.3

1.23

0.55

3.5

6.1

1.8

3.3

150

16.8

1.68

V/ms V/ms

ms ms

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A A A

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DEMO MANUAL DC1886B

JUMPERS AND LEDS

Two demo board jumpers, JP1 and JP2, allow selection of controller operation:

• JP1 TIMER DURATION: Set to FIXED 2ms position for the internal 2ms timer period (FIXED 2ms not recom mended for LTC4232-1 during auto-retry) or ADJUSTABLE determined by TIMER capacitor C1 (12ms for LTC4232 and 1.2ms for LTC4232-1). (Default position: ADJUSTABLE)

• JP2 AUTORETRY: Set to ON for auto-retry or OFF for latchoff on overcurrent fault. (Default position: OFF)

When selecting AUTORETRY option for the circuit with a predominantly resistive load, particularly for LTC4232-1, pay special attention to the power MOSFET thermal con dition. The initial low current limit (due to the foldback characteristic) can power the load only during a very short time, and the MOSFET will experience the maximum cur rent limit for almost all of the remaining power up period. This may exceed the MOSFET SOA, if allowed to autoretry.

Four LEDs indicate the state of the hot swap circuit. Red LEDs, D3 and D5, provide fault status and low output voltage (it is a NOT power good signal). Two green LEDs, D2 and D4, signal the presence of valid input and output voltages.

Figure 1. Proper Measurement Equipment Setup

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QUICK START PROCEDURE

DEMO MANUAL DC1886B

Demonstration circuit 1886B is easy to set up to evaluate the performance of the LTC4232 or LTC4232-1. Refer to Figure 1 for the proper measurement equipment setup and follow the procedure below.

1. Place jumpers in the following positions:

JP1 TIMER DURATION FIXED 2ms

JP2 AUTORETRY OFF

2. With power off, connect 12V power supply terminals to the VDD (E1) and GND (E3) turrets.

3. Turn on the 12V power supply and verify the output voltage between the V Two green LEDs, D2 and D4 should light up.

4. Check the current limit using an electronic or resis tive load. It should be in the range of 5A to 6.1A if an overcurrent condition occurs while the output is high (after powering up properly). If the output is shorted initially, the load current will be limited in the range of

1.2A to 1.8A due to the foldback characteristic. Current may be monitored on the IMON turret. The IMON signal scale is 0.4V/A.

(E2) and GND (E4) turrets.

OUT

5. Check the output voltage slew rate with an oscilloscope, without a load connected. It should take from 22ms to 80ms for LTC4232, and from 3.0ms to 7.0ms for LTC4232-1.

6. For DC1886B-A (LTC4232) use a 2000μF capacitive load to demonstrate that power up mode completes successfully. Use a current probe to verify that inrush current is limited initially by the foldback characteristic and later by the low output voltage slew rate.

7. For DC1886B-A use a 6000μF capacitive load to dem onstrate that the part not only enters into the current limit state but operates in this state until the timer period expires. It is not a successful power up.

8. For DC18886B-B use a 800μF capacitive load to demon strate a successful power up mode. The controller will operate in current limit almost all of the timer period.

9. For DC1886B-B use a 3000μF capacitive load to demonstrate an unsuccessful power up transient. The operating point does not leave current limit during the whole timer period. It will then time out and turn off.

An overcurrent condition is indicated by the red LED

FLT(D3) and red LED PG (D5).

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DEMO MANUAL DC1886B

PARTS LIST

ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER

Required Circuit Components

1 0 CIN1, COUT2 CAP., SANYO\16X25\H OPT

2 1 COUT1 CAP., TANT, 22µF 25V, 20%, 7343 AVX, TPSD226M025R0200

3 1 C2 CAP., X5R, 1µF 25V, 0603 AVX, 06033D105KAT2A

4 1 D1 DIODE, 400W TRANSIENT VOLTAGE

SUPPRESSOR, SMA-DIODE

5 2 D2, D4 LED, GREEN, LED-ROHM-SML-010FT ROHM, SML-010FTT86L

6 2 D3, D5 LED, RED, LED-ROHM-SML-010VT ROHM, SML-010VTT86L

7 4 E1, E2, E3, E4 TURRET, TEST PIN, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0

8 8 E5-E12 TURRET, TEST PIN, 0.064" MILL-MAX, 2308-2-00-80-00-00-07-0

9 2 JP1, JP2 JMP, HD1X3, 0.079CC SULLIN, NRPN031PAEN-RC

10 1 RMON RES., CHIP, 20k, 1/8W, 5%, 0805 YAGEO, RC0805JR-0720KL

11 0 RSET RES., CHIP, 0805 O PT

12 4 R1, R2, R3, R5 RES., CHIP, 3.3k, 1/16W, 5%, 0603 YAGEO, RC0603JR-073K3L

13 1 R4 RES., CHIP, 150k, 1/16W, 5%, 0603 YAGEO, RC0603JR-07150KL

14 3 R6, R7, R8 RES., CHIP, 20k, 1/16W, 5%, 0603 YAGEO, RC0603JR-0720KL

15 1 R9 RES., CHIP, 140k, 1/16W, 5%, 0603 YAGEO, RC0603JR-07140KL

16 1 R10 RES., CHIP, 226k, 1/16W, 5%, 0603 YAGEO, RC0603JR-07226KL

17 2 SHUNT, 0.079" CENTER SAMTEC, 2SN-BK-G

DC1886B-A Required Circuit Components

1 DC1886B-GENERAL BOM

1 C1 CAP., X5R, 1µF 25V, 0603 AVX, 06033D105KAT2A

0 CGS, CGATE CAP., 0603 OPT

0 RGATE RES., 0603 OPT

1 U1 I.C., LTC4232IDHC, DFN16DHC LINEAR TECH., LTC4232IDHC

DC1886B-B Required Circuit Components

1 DC1886B-GENERAL BOM

1 C1 CAP., X5R, 0.1µF 25V, 0603 AVX, 06033D104KAT2A

0 CGS CAP., X7R, 3300pF 100V, 5%, 0603 AVX, 06031C332JAT2A

1 CGATE CAP., X7R, 0.01µF 100V, 5%, 0603 AVX, 06031C103JAT2A

1 RGATE RES., CHIP, 100k, 1/10W, 1% 0603 NIC, NRC06F1003TRF

1 U1 I.C., LTC4232IDHC-1, DFN16DHC LINEAR TECH., LTC4232IDHC-1

DIODES INC., SMAJ22A-13-F

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SCHEMATIC DIAGRAM

06-06-14

VLADIMIR O.

VOUT

12V / 5A

COUT2

OPT+COUT2

OPT

DEMO MANUAL DC1886B

GNDE4GND

ISET

IMON

E10

E11

IMON

www.linear.com

SHEET OF

E8PGE8

VOUT

COUT1

22uF

25V

7343

COUT1

22uF

25V

7343

REVISION HISTORY

DESCRIPTION DATEAPPROVEDECO REV

REVISION HISTORY

DESCRIPTION DATEAPPROVEDECO REV

REVISION HISTORY

DESCRIPTION DATEAPPROVEDECO REV

REBUILD WITH CHANGE2

CGS*CGS

OUT

OUT8OUT

U1*U1

VDD

3.3kR33.3k

3.3kR53.3k

150kR4150k

GREEND4GREEN

2 1

REDD5RED

2 1

RSET

OPT

0805

RSET

OPT

0805

20kR620k

GATE

RGATE*RGATE

CGATE*CGATE

RMON

20k

RMON

20k

0805

ISET

IMON

GND

SENSE

FLT

TIMER4INTVCC

1uF

25VC21uF

25V

OPT

RGATESUFFIX

OPT

0.01uF

CGATE

OPT

CGSC1

0.033uF

1uF

0.1uF

LTC4232IDHC

LTC4232IDHC - 1B 100k

ASSY U1

Fax: (408)434-0507

Milpitas, CA 95035

Phone: (408)432-1900

1630 McCarthy Blvd.

LTC Confidential-For Customer Use Only

Fax: (408)434-0507

Milpitas, CA 95035

Phone: (408)432-1900

1630 McCarthy Blvd.

LTC Confidential-For Customer Use Only

Fax: (408)434-0507

Milpitas, CA 95035

Phone: (408)432-1900

1630 McCarthy Blvd.

LTC Confidential-For Customer Use Only

TECHNOLOGY

IC NO. REV.

SCHEMATIC

5A INTEGRATED HOT SWAP CONTROLLER

SIZE

TITLE:

KIM T.

VLADIMIR O.

APPROVALS

PCB DES.

APP ENG.

LTC4232IDHC / -1

DEMO CIRCUIT 1886B

06/06/2014, 04:50 PM 1 1

N/A

DATE:

SCALE = NONE

C1*C1

3.3kR23.3k

CIN1

OPT+CIN1

OPT

REDD3RED

2 1

R10

226k

R10

226k

140kR9140k

20kR820k

20kR720k

3 2 1

JP2JP2

AUTORETRY

OFF ON

CUSTOMER NOTICE

LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A

CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;

HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO

VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL

APPLICATION. COMPONENT SUBSTITUTION AND PRINTED

CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT

PERFORMANCE OR RELIABILITY. CONTACT LINEAR

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A

CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;

HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO

VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL

APPLICATION. COMPONENT SUBSTITUTION AND PRINTED

CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT

LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A

CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;

PERFORMANCE OR RELIABILITY. CONTACT LINEAR

HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO

VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL

APPLICATION. COMPONENT SUBSTITUTION AND PRINTED

CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT

PERFORMANCE OR RELIABILITY. CONTACT LINEAR

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

3.3kR13.3k

VDD

12V

VDD

D D

GREEND2GREEN

2 1

SMAJ22A

Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

GNDE3GND

E6OVE6

E5UVE5

FLTE7FLT

TIMERE9TIMER

C C

E12

JP1JP1

1 2 3

INTVCC

TIMER

DURATION

FIXED ADJUSTABLE

B B

ALL CAPACITORS ARE IN MICROFARADS, 0603.

NOTES: UNLESS OTHERWISE SPECIFIED

2. INSTALL SHUNTS AS SHOWN.

1. ALL RESISTORS ARE IN OHMS, 0402.

A A

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DEMO MANUAL DC1886B

DEMONSTRATION BOARD IMPORTANT NOTICE

Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:

This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.

If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.

The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or agency certified (FCC, UL, CE, etc.).

No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,

customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.

LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.

Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and

observe good laboratory practice standards. Common sense is encouraged.

This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer.

Mailing Address:

Linear Technology

1630 McCarthy Blvd.

Milpitas, CA 95035

Linear Technology Corporation

1630 McCarthy Blvd., Milpitas, CA 95035-7417

(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com

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LT 0814 REV A • PRINTED IN USA

 LINEAR TECHNOLOGY CORPORATION 2012