Analog Devices AD2S83 e Datasheet

Variable Resolution,
A3
RIPPLE CLOCK
R4
VCO
I/P
TRACKING RATE SELECTION
R6
VELOCITY SIGNAL
INTEGRATOR I/P
BANDWIDTH SELECTION
R3
C3
REFERENCE I/P
HF FILTER
R2
C2
C1
R1
DEMOD O/P
INTEGRATOR
O/P
DIRECTION
BUSY
DIG
GND
16
DATA BITS
SC1
SC2
DATA LOAD
BYTE SELECT
5V
+12V
–12V
GND
COS
SIG
GND
SIN
AC ERROR O/P
VCO
O/P
C7
AD2S83
R7 3K3
C6 390pF
R8
–12V
+12V
OFFSET ADJUST
R9
R5
C4
C5
R – 2R DAC
PHASE
SENSITIVE
DETECTOR
VCO + DATA TRANSFER LOGIC
16-BIT UP/DOWN COUNTER
SEGMENT SWITCHING
OUTPUT DATA LATCH
A2
A1
ENABLE INHIBIT
a
FEATURES Tracking R/D Converter High Accuracy Velocity Output High Max Tracking Rate 1040 RPS (10 Bits) 44-Lead PLCC Package 10-, 12-, 14-, or 16-Bit Resolution Set by User Ratiometric Conversion Stabilized Velocity Reference Dynamic Performance Set by User Industrial Temperature Range
APPLICATIONS DC and AC Servo Motor Control Process Control Numerical Control of Machine Tools Robotics Axis Control
Resolver-to-Digital Converter
FUNCTIONAL BLOCK DIAGRAM
GENERAL DESCRIPTION
The AD2S83 is a monolithic 10-, 12-, 14-, or 16-bit tracking resolver-to-digital converter.
The converter allows users to select their own resolution and dynamic performance with external components. The converter allows users to select the resolution to be 10, 12, 14, or 16 bits and to track resolver signals rotating at up to 1040 revs per second (62,400 rpm) when set to 10-bit resolution.
The AD2S83 converts resolver format input signals into a paral­lel natural binary digital word using a ratiometric tracking con­version method. This ensures high noise immunity and tolerance of long leads allowing the converter to be located remote from the resolver.
The position output from the converter is presented via 3-state output pins which can be configured for operations with 8- or 16-bit bus. BYTE SELECT, ENABLE and INHIBIT pins ensure easy data transfer to 8- and 16-bit data bus, and outputs are provided to allow for cycle or pitch counting in external counters.
A precise analog signal proportional to velocity is also available and will replace a tachogenerator.
The AD2S83 operates over reference frequencies in the range 0 Hz to 20,000 Hz.
REV. E
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
PRODUCT HIGHLIGHTS
High Accuracy Velocity Output. A precision analog velocity
signal with a typical linearity of ±0.1% and reversion error less than ±0.3% is generated by the AD2S83. The provision of this signal removes the need for mechanical tachogenerators used in servo systems to provide loop stabilization and speed control.
Resolution Set by User. Two control pins are used to select the resolution of the AD2S83 to be 10, 12, 14 or 16 bits allow­ing optimum resolution for each application.
Ratiometric Tracking Conversion. This technique provides continuous output position data without conversion delay. It also provides noise immunity and tolerance of harmonic distor­tion on the reference and input signals.
Dynamic Performance Set by the User. By selecting external resistor and capacitor values the user can determine band­width, maximum tracking rate and velocity scaling of the converter to match the system requirements. The component values are easy to select using the free component selection software design aid.
MODELS AVAILABLE
Information on the models available is given in the Ordering Guide.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781/329-4700 World Wide Web Site: http://www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 2000
AD2S83–SPECIFICATIONS
(VS = 12 V dc 5%; VL = 5 V dc  10%; TA = –40C to +85C)
Parameter Conditions Min Typ Max Unit
SIGNAL INPUTS (SIN, COS)
Frequency
1
0 20,000 Hz Voltage Level 1.8 2.0 2.2 V rms Input Bias Current 60 150 nA Input Impedance 1.0 M
REFERENCE INPUT (REF)
Frequency 0 20,000 Hz Voltage Level 1.0 8.0 V pk Input Bias Current 60 150 nA Input Impedance 1.0 M
PERFORMANCE
Repeatability 1 LSB Allowable Phase Shift (Signals to Reference) –10 +10 Degree Max Tracking Rate 10 Bits 1040 rps
12 Bits 260 rps 14 Bits 65 rps 16 Bits 16.25 rps
Bandwidth User Selectable
ACCURACY
Angular Accuracy A, I
8 +1 LSB arc min Monotonicity Guaranteed Monotonic Missing Codes (16-Bit Resolution) A, I 4 Codes
VELOCITY SIGNAL
LINEARITY
2, 3, 4
AD2S83AP
0 kHz–500 kHz –40°C to +85°C ±0.15
0.5 MHz–1 MHz –40°C to +85°C ±0.25
0.25 % FSR
1.0 % FSR
AD2S83IP
0 kHz–500 kHz –40°C to +85°C ±0.25
0.5 MHz–1 MHz –40°C to +85°C ±0.25
0.5 % FSR
1.0 % FSR
Reversion Error
AD2S83AP –40°C to +85°C ±0.5 AD2S83IP –40°C to +85°C ±1.0
DC Zero Offset
5
±3mV
1.0 % O/P
1.5 % O/P
Gain Scaling Accuracy ±1.5 3 % FSR Output Voltage 1 mA Load ±8V Dynamic Ripple Mean Value 1.0 % rms O/P
INPUT/OUTPUT PROTECTION
Analog Inputs Overvoltage Protection ±8V Analog Outputs Short Circuit O/P Protection ±5.6 ±8 ±10.4 mA
DIGITAL POSITION
Resolution 10, 12, 14, and 16 Bits Output Format Bidirectional Natural Binary Load 3 LSTTL
INHIBIT
6
Sense Logic LO to INHIBIT Time to Stable Data 240 390 490 ns
ENABLE
6
Logic LO Enables Position Output Logic HI Outputs in High
ENABLE6/Disable Time Impedance State 35 110 ns
BYTE SELECT
6
Sense Logic HI MS Byte DB1–DB8 Logic LO LS Byte DB1–DB8 Time to Data Available 60 140 ns
SHORT CYCLE INPUTS Internally Pulled High via
100 k to +V
S
SC1 SC2
0 0 10-Bit Resolution 0 1 12-Bit Resolution 1 0 14-Bit Resolution 1 1 16-Bit Resolution
–2–
REV. E
AD2S83
Parameter Conditions Min Typ Max Unit
COMPLEMENT Internally Pulled High via 100 k
DATA LOAD
Sense Internally Pulled High via 100 k 150 300 ns
6, 7
BUSY
Sense Logic HI When Position O/P Changing Width 150 350 ns Load Use Additional Pull-Up (See Figure 2) 1 LSTTL
DIRECTION
6
Sense Logic HI Counting Up
Max Load 3 LSTTL
RIPPLE CLOCK
6
Sense Logic HI
Width Dependent on Input Velocity 300 ns Reset Before Next Busy Load 3 LSTTL
DIGITAL INPUTS
Input High Voltage, V
Input Low Voltage, V
IH
IL
DIGITAL INPUTS
Input High Current, I
Input Low Current, I
IH
IL
DIGITAL INPUTS
Low Voltage, V
Low Current, I
IL
IL
DIGITAL OUTPUTS
High Voltage, V
Low Voltage, V
NOTES
1
Angular accuracy is not guaranteed <50 Hz reference frequency.
2
Linearity derates from 500 kHz–1000 kHz @ 0.0017%/kHz.
3
Refer to Definition of Linearity, “The AD2S83 as a Silicon Tachogenerator.”
4
Worst case reversion error at temperature extremes.
5
Velocity output offset dependent on value for R6.
6
Refer to timing diagram.
7
Busy pulse guaranteed up to a VCO rate of 900 kHz.
All min and max specifications are guaranteed. Specifications in boldface are tested on all production units at final electrical test. Specifications subject to change without notice.
OH
OL
. Logic LO to Activate;
to +V
S
No Connect for Normal Operation
. Logic LO Allows
to +V
S
Data to be Loaded into the Counters from the Data Lines
Logic LO Counting Down
All 1s to All 0s All 0s to All 1s
INHIBIT, ENABLE 2.0 V DB1–DB16, Byte Select
= ±11.4 V, VL = 5.0 V
±V
S
INHIBIT, ENABLE 0.8 V DB1–DB16, Byte Select ±VS = ±12.6 V, VL = 5.0 V
INHIBIT, ENABLE
100 µA
DB1–DB16 ±V
= ±12.6 V, VL = 5.5 V
S
INHIBIT, ENABLE
100 µA
DB1–DB16, Byte Select ±VS = ±12.6 V, VL = 5.5 V
ENABLE = HI 1.0 V SC1, SC2, DATA LOAD ±V
= ±12.0 V, VL = 5.0 V
S
ENABLE = HI –400 µA SC1, SC2, DATA LOAD ±VS = ±12.0 V, VL = 5.0 V
DB1–DB16 2.4 V RIPPLE CLK, DIR
= ±12.0 V, VL = 4.5 V
±V
S
= 100 µA
I
OH
DB1–DB16 0.4 V RIPPLE CLK, DIR ±V
= ±12.0 V, VL = 5.5 V
S
IOL = 1.2 mA
REV. E
–3–
AD2S83–SPECIFICATIONS
(VS = 12 V dc 5%; VL = 5 V dc  10%; TA = –40C to +85C)
Parameter Conditions Min Typ Max Unit
THREE-STATE LEAKAGE DB1–DB16 Only
Current I
L
±VS = ±12.0 V, VL = 5.5 V V
= 0 V
OL
= ±12.0 V, VL = 5.5 V
±V
S
V
= 5.0 V
OH
20 µA
20 µA
RATIO MULTIPLIER
AC Error Output Scaling 10 Bit 177.6 mV/Bit
12 Bit 44.4 mV/Bit 14 Bit 11.1 mV/Bit 16 Bit 2.775 mV/Bit
PHASE SENSITIVE DETECTOR
Output Offset Voltage 12 mV Gain
In Phase w.r.t. REF –0.882 –0.9 –0.918 V rms/V dc In Quadrature w.r.t. REF ±0.02 V rms/V dc
Input Bias Current 60 150 nA Input Impedance 1.0 M Input Voltage ±8V
INTEGRATOR
Open-Loop Gain At 10 kHz 57 60 63 dB Dead Zone Current (Hysteresis) 90 100 110 nA/LSB Input Offset Voltage 15 mV Input Bias Current 60 150 nA Output Voltage Range 8 V
VCO
Maximum Rate 1.1 MHz VCO Rate +ve DIR 8.25 8.50 8.75 kHz/µA
–ve DIR 8.25 8.50 8.75 kHz/µA
VCO Power Supply Sensitivity
Rate +V
–V
S
S
+0.5 %/V
–0.5 %/V Input Offset Voltage 3mV Input Bias Current 12 50 nA Input Bias Current Tempco +0.22 nA/°C Linearity of Absolute Rate
AD2S83AP
0 kHz–500 kHz ±0.15 0.25 % FSR
0.5 MHz–1 MHz ±0.25 1.0 % FSR
AD2S83IP
0 kHz–500 kHz ±0.25 0.5 % FSR
0.5 MHz–1 MHz ±0.25 1.0 % FSR
Reversion Error
AD2S83AP ±0.5 1.0 % Output AD2S83IP ±1.0 1.5 % Output
POWER SUPPLIES
Voltage Levels
+V –V +V
S
S
L
+11.4 +12.6 V –11.4 –12.6 V +4.5 +5 +V
S
V
Current
±I
S
±I
S
±I
L
All min and max specifications are guaranteed. Specifications in boldface are tested on all production units at final electrical test.
Specifications subject to change without notice.
±VS @ ±12 V ±12 23 mA ±VS @ ±12.6 V ±19 30 mA
+VL @ ±5.0 V ±0.5 1.5 mA
ORDERING GUIDE
Temperature Package Package
Model Range Accuracy Description Option
AD2S83AP –40°C to +85°C 8 arc min Plastic Leaded Chip Carrier P-44A AD2S83IP –40°C to +85°C 8 arc min Plastic Leaded Chip Carrier P-44A
–4–
REV. E
AD2S83
WARNING!
ESD SENSITIVE DEVICE
ABSOLUTE MAXIMUM RATINGS1
2
+V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +13 V dc
S
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –13 V dc
–V
S
+V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +V
L
Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +13 V to –V
SIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +13 V to –V
COS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +13 V to –V
(with respect to GND)
S
S
S
S
Any Logical Input . . . . . . . . . . . . . . . . . . –0.4 V dc to +VL dc
Demodulator Input . . . . . . . . . . . . . . . . . . . . . . . +13 V to –V
Integrator Input . . . . . . . . . . . . . . . . . . . . . . . . . . +13 V to –V
VCO Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +13 V to –V
S
S
S
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 mW
Operating Temperature
Industrial (AP, IP) . . . . . . . . . . . . . . . . . . . –40°C to +85°C
Storage Temperature . . . . . . . . . . . . . . . . . . –65°C to +150°C
Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . . 300°C
CAUTION
1
Absolute Maximum Ratings are those values beyond which damage to the device may occur.
2
Correct polarity voltages must be maintained on the +VS and –VS pins.
RECOMMENDED OPERATING CONDITIONS
Power Supply Voltage (+VS, –VS) . . . . . . . . . . ± 12 V dc ± 5%
Power Supply Voltage V
. . . . . . . . . . . . . . . . . +5 V dc ± 10%
L
Analog Input Voltage (SIN and COS) . . . . . . . 2 V rms ± 10%
Analog Input Voltage (REF) . . . . . . . . . . . . . . 1 V to 8 V peak
Signal and Reference Harmonic Distortion . . . . . . 10% (max)
Phase Shift Between Signal and Reference . . . ±10 Degrees (max) Ambient Operating Temperature Range
Industrial (AP, IP) . . . . . . . . . . . . . . . . . . . –40°C to +85°C
PIN CONFIGURATION
VCO I/P
VCO O/P
INTEGRATOR O/P
39
–V
38
RIPPLE CLOCK
37
DIRECTION
36
BUSY
35
COMP
34
DATA LOAD
33
SC1
SC2
32
DIGITAL GND
31
30
INHIBIT
NC
29
L
+V
ENABLE
BYTE SELECT
S
7
SIN I/P
8
+V
S
9
NC
DB2
DB3
DB4
DB5
DB6
DB7
DB8
10
11
12
13
14
15
16
17
(MSB) DB1
NC = NO CONNECT
ANALOG GND
AC ERROR O/P
DEMOD O/P
SIGNAL GND
5642414043
181920 21 2 2 23 24 252627 28
DB9
DB10
COS I/P
4
DB11
REF I/P
21443
AD2S83
TOP VIEW
(Not to Scale)
DB13
DB12
DEMOD I/P
PIN 1 IDENTIFIER
DB15
DB14
INTEGRATOR I/P
(LSB) DB16
PIN FUNCTION DESCRIPTIONS
P
in
Nos. Mnemonic Description
1 DEMOD O/P Demodulator Output
2 REFERENCE I/P Reference Signal Input
3 AC ERROR O/P Ratio Multiplier Output
4 COS Cosine Input
5 ANALOG GND Power Ground
6 SIGNAL GND Resolver Signal Ground
7 SIN Sine Input
8+V
S
Positive Power Supply
10–25 DB1–DB16 Parallel Output Data
26 +V
L
Logic Power Supply
27 ENABLE Logic HI—Output Data Pins in
High Impedance State Logic LO—Presents Active Data to the Output Pins
28 BYTE SELECT Logic HI—Most Significant Byte to
DB1–DB8 Logic LO—Least Significant Byte to DB1–DB8
30 INHIBIT Logic LO Inhibits Data Transfer
to Output Latches
31 DIGITAL GND Digital Ground
32, 33 SC2–SC1 Select Converter Resolution 34 DATA LOAD Logic LO DB1–DB16 Inputs
Logic HI DB1–DB16 Outputs
35 COMPLEMENT Active Logic LO
36 BUSY Converter Busy, Data not Valid
While Busy HI
37 DIRECTION Logic State Defines Direction of
Input Signal Rotation
38 RIPPLE CLOCK Positive Pulse When Converter Output
Changes from 1s to All 0s or Vice Versa
39 –V
S
Negative Power Supply
40 VCO I/P VCO Input
41 VCO O/P VCO Output
42 INTEGRATOR O/P Integrator Output
43 INTEGRATOR I/P Integrator Input
44 DEMOD I/P Demodulator Input
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD2S83 feature proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high-energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
REV. E
–5–
AD2S83
Bit Weight Table
Binary Resolution Degrees Minutes Seconds Bits (N) (NN) /Bit /Bit /Bit
0 1 360.0 21600.0 1296000.0 1 2 180.0 10800.0 648000.0 2 4 90.0 5400.0 324000.0 3 8 45.0 2700.0 162000.0 4 16 22.5 1350.0 81000.0
5 32 11.25 675.0 40500.0 6 64 5.625 337.5 20250.0 7 128 2.8125 168.75 10125.0 8 256 1.40625 84.375 5062.5 9 512 0.703125 42.1875 2531.25
10 1024 0.3515625 21.09375 1265.625 11 2048 0.1757813 10.546875 632.8125 12 4096 0.0878906 5.273438 316.40625 13 8192 0.0439453 2.636719 158.20313 14 16384 0.0219727 1.318359 79.10156
15 32768 0.0109836 0.659180 39.55078 16 65536 0.0054932 0.329590 19.77539 17 131072 0.0027466 0.164795 9.88770 18 262144 0.0013733 0.082397 4.94385
CONNECTING THE CONVERTER
The power supply voltages connected to +VS and –VS pins should be +12 V dc and –12 V dc and must not be reversed. The voltage applied to V
can be +5 V dc to +VS.
L
It is recommended that the decoupling capacitors are connected in parallel between the power lines +V
, –VS and ANALOG
S
GROUND adjacent to the converter. Recommended values are 100 nF (ceramic) and 10 µF (tantalum). Also capacitors of 100 nF and 10 µF should be connected between +V
and
L
DIGITAL GROUND adjacent to the converter.
When more than one converter is used on a card, separate de­coupling capacitors should be used for each converter.
The resolver connections should be made to the SIN and COS inputs, REFERENCE INPUT and SIGNAL GROUND as shown in Figure 11 and described in the Connecting the Resolver section.
The two signal ground wires from the resolver should be joined at the SIGNAL GROUND pin of the converter to minimize the coupling between the sine and cosine signals. For this reason it is also recommended that the resolver is connected using indi­vidually screened twisted pair cables with the sine, cosine and reference signals twisted separately.
SIGNAL GROUND and ANALOG GROUND are connected internally. ANALOG GROUND and DIGITAL GROUND must be connected externally and as close to the converter as possible.
The external components required should be connected as shown in Figure 1.
CONVERTER RESOLUTION
Two major areas of the AD2S83 specification can be selected by the user to optimize the total system performance. The resolu­tion of the digital output is set by the logic state of the inputs SC1 and SC2 to be 10, 12, 14 or 16 bits; and the dynamic char­acteristics of bandwidth and tracking rate are selected by the choice of external components.
The choice of the resolution will affect the values of R4 and R6 which scale the inputs to the integrator and the VCO respec­tively (see Component Selection section). If the resolution is changed, then new values of R4 and R6 must be switched into the circuit.
Note: When changing resolution under dynamic conditions, do it when the BUSY is low, i.e., when data is not changing.
SIN
SIG GND
COS
GND
RIPPLE CLOCK
+12V
–12V
DATA LOAD
SC1
A1
SEGMENT SWITCHING
A2
16-BIT UP/DOWN COUNTER
ENABLE
SC2
R - 2R DAC
OUTPUT DATA LATCH
16 DATA BITS
Figure 1. Connection Diagram
AC ERROR O/P
A3
AD2S83
BYTE SELECT
HF FILTER
C1
R1
5V
GND
R2
C2
PHASE SENSITIVE DETECTOR
REFERENCE I/P
C3
DEMOD O/P
VCO + DATA TRANSFER LOGIC
DIRECTIONBUSYDIG
R3
R4
INTEGRATOR
O/P
INHIBIT
OFFSET ADJUST
+12V
INTEGRATOR
VCO
I/P
VCO
O/P
R9
R8
BANDWIDTH SELECTION
I/P
R6
C7
150pF
R7 3K3
C6 390pF
–12V
C5
R5
C4
TRACKING RATE SELECTION
VELOCITY SIGNAL
–6–
REV. E
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