View AD8510BR_239905.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

Precision, Very Low Noise, Low Input Bias Current, Wide Bandwidth JFET Operational Amplifiers
AD8510/AD8512/AD8513
FEATURES
Fast settling time: 500 ns to 0.1% Low offset voltage: 400 V max Low TCVOS: 1 V/C typ Low input bias current: 25 pA typ Dual-supply operation: 5 V to 15 V Low noise: 8 nV/Hz Low distortion: 0.0005% No phase reversal Unity gain stable
OUT A -IN A +IN A V- 1
PIN CONFIGURATIONS
8 V+ OUT B
02729-D-001
OUT A -IN A +IN A V-
V+
AD8512
TOP VIEW (Not to Scale) 4 5
AD8512
TOP VIEW (Not to Scale)
OUT B -IN B +IN B
02729-D-002
02729-D-006
-IN B +IN B
Figure 1. 8-Lead MSOP (RM Suffix)
NC -IN +IN V- NC
Figure 2. 8-Lead SOIC (R Suffix)
NC -IN NC
AD8510
TOP VIEW (Not to Scale)
V+
02729-D-003
AD8510
TOP VIEW (Not to Scale)
V+ OUT NC
02729-D-004
OUT NC
+IN V-
APPLICATIONS
Instrumentation Multipole filters Precision current measurement Photodiode amplifiers Sensors Audio
Figure 3. 8-Lead MSOP (RM Suffix)
OUT A 1 -IN A 2 +IN A 3 V+ 4
14 13
Figure 4. 8-Lead SOIC (R Suffix)
1 14
OUT D -IN D +IN D
OUT A -IN A +IN A V+ +IN B
02729-D-005
OUT D -IN D
AD8513
12
AD8513
TOP VIEW (Not to Scale)
+IN D V- +IN C -IN C OUT C
11 V- TOP VIEW +IN B 5 (Not to Scale) 10 +IN C
-IN B 6 OUT B 7
9 8
-IN C OUT C
-IN B OUT B
7 8
Figure 5. 14-Lead SOIC (R Suffix)
Figure 6. 14-Lead TSSOP (RU Suffix)
GENERAL DESCRIPTION
The AD8510, AD8512, AD8513 are single-, dual-, and quadprecision JFET amplifiers that feature low offset voltage, input bias current, input voltage noise, and input current noise. The combination of low offsets, low noise, and very low input bias currents makes these amplifiers especially suitable for high impedance sensor amplification and precise current measurements using shunts. The combination of dc precision, low noise, and fast settling time results in superior accuracy in medical instruments, electronic measurement, and automated test equipment. Unlike many competitive amplifiers, the AD8510/ AD8512/AD8513 maintain their fast settling performance even with substantial capacitive loads. Unlike many older JFET amplifiers, the AD8510/AD8512/ AD8513 do not suffer from output phase reversal when input voltages exceed the maximum common-mode voltage range. Fast slew rate and great stability with capacitive loads make the AD8510/AD8512/AD8513 a perfect fit for high performance filters. Low input bias currents, low offset, and low noise result in a wide dynamic range of photodiode amplifier circuits. Low noise and distortion, high output current, and excellent speed make the AD8510/AD8512/AD8513 a great choice for audio applications. The AD8510/AD8512 are both available in 8-lead narrow SOIC and 8-lead MSOP packages. MSOP packaged parts are only available in tape and reel. The AD8513 is available in 14-lead SOIC and TSSOP packages. The AD8510/AD8512/AD8513 are specified over the -40C to +125C extended industrial temperature range.
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 that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.326.8703 (c) 2004 Analog Devices, Inc. All rights reserved.
AD8510/AD8512/AD8513 TABLE OF CONTENTS
Specifications............................................................................................3
Total Noise Including Source Resistors................................... 13 Settling Time............................................................................... 14 Overload Recovery Time .......................................................... 14 Capacitive Load Drive ............................................................... 14 Open-Loop Gain and Phase Response.................................... 15 Precision Rectifiers..................................................................... 16 I-V Conversion Applications .................................................... 17
Outline Dimensions ..............................................................................19
Electrical Characteristics ............................................................. 4
Absolute Maximum Ratings ..................................................................6
ESD Caution.................................................................................. 6
Typical Performance Characteristics ....................................................7 General Application Information........................................................13
Input Overvoltage Protection ................................................... 13 Output Phase Reversal............................................................... 13 THD + Noise............................................................................... 13
Ordering Guide .......................................................................... 20
REVISION HISTORY
6/04--Data Sheet Changed from Rev. D to Rev. E Changes to Format .............................................................Universal Changes to Specifications ................................................................ 3 Updated Outline Dimensions ....................................................... 19 10/03--Data Sheet Changed from Rev. C to Rev. D Added AD8513 Model ......................................................Universal Changes to Specifications ................................................................ 3 Added Figures 36 through 40........................................................ 10 Added new Figures 55 and 57....................................................... 17 Changes to Ordering Guide .......................................................... 20 9/03--Data Sheet Changed from Rev. B to Rev. C Changes to Ordering Guide ........................................................... 4 Updated Figure 2 ............................................................................ 10 Changes to Input Overvoltage Protection section .................... 10 Changes to Figures 10 and 11 ....................................................... 12 Changes to Photodiode Circuits section ..................................... 13 Changes to Figures 13 and 14 ....................................................... 13 Deleted Precision Current Monitoring section .......................... 14 Updated Outline Dimensions ...................................................... 15 3/03--Data Sheet Changed from Rev. A to Rev. B Updated Figure 5 ............................................................................ 11 Updated Outline Dimensions....................................................... 15 8/02--Data Sheet Changed from Rev. 0 to Rev. A Added AD8510 Model .......................................................Universal Added Pin Configurations ...............................................................1 Changes to Specifications.................................................................2 Changes to Ordering Guide .............................................................4 Changes to TPCs 2 and 3..................................................................5 Added new TPCs 10 and 12.............................................................6 Replaced TPC 20 ...............................................................................8 Replaced TPC 27 ...............................................................................9 Changes to General Application Information Section .............. 10 Changes to Figure 5........................................................................ 11 Changes to I-V Conversion Applications Section...................... 13 Changes to Figures 13 and 14 ....................................................... 13 Changes to Figure 17...................................................................... 14
Rev. E | Page 2 of 20
AD8510/AD8512/AD8513 SPECIFICATIONS
@ VS = 5 V, VCM = 0 V, TA = 25C, unless otherwise noted. Table 1.
Parameter INPUT CHARACTERISTICS Offset Voltage (B Grade)1 Offset Voltage (A Grade) Input Bias Current Symbol VOS -40C < TA < +125C VOS -40C < TA < +125C IB -40C < TA < +85C -40C < TA < +125C Input Offset Current IOS -40C < TA < +85C -40C < TA < +125C Input Capacitance Differential Common-Mode Input Voltage Range Common-Mode Rejection Ratio Large Signal Voltage Gain Offset Voltage Drift (B Grade)1 Offset Voltage Drift (A Grade) OUTPUT CHARACTERISTICS Output Voltage High Output Voltage Low Output Voltage High Output Voltage Low Output Voltage High Output Voltage Low Output Current POWER SUPPLY Power Supply Rejection Ratio Supply Current/Amplifier AD8510/AD8512/AD8513 AD8510/AD8512 AD8513 DYNAMIC PERFORMANCE Slew Rate Gain Bandwidth Product Settling Time THD + Noise Phase Margin NOISE PERFORMANCE Voltage Noise Density 12.5 11.5 CMRR AVO VOS/T VOS/T VOH VOL VOH VOL VOH VOL IOUT PSRR ISY VCM = -2.0 V to +2.5 V RL = 2 k, VO = -3 V to +3 V -2.0 86 65 +2.5 100 107 0.9 1.7 +4.3 -4.9 + 4.2 -4.9 +4.1 -4.8 54 130 2.0 2.3 2.5 2.75 5 21 0.1 Conditions Min Typ 0.08 Max 0.4 0.8 0.9 1.8 75 0.7 7.5 50 0.3 0.5 Unit mV mV mV mV pA nA nA pA nA nA pF pF V dB V/mV V/C V/C V V V V V V mA dB mA mA mA V/s MHz s % Degrees nV/Hz nV/Hz nV/Hz nV/Hz V p-p
5 12
RL = 10 k -40C < TA < +125C RL = 2 k, -40C < TA < +125C RL = 600 -40C < TA < +125C
+4.1 +3.9 +3.7 40
-4.7 -4.5 -4.2
VS = 4.5 V to 18 V VO = 0 V -40C < TA < +125C -40C < TA < +125C
86
SR GBP tS THD + N O en
RL = 2 k To 0.1%, 0 V to 4 V Step, G = +1 1 kHz, G = +1, RL = 2 k
20 8 0.4 0.0005 44.5 34 12 8.0 7.6 2.4
Peak-to-Peak Voltage Noise
en p-p
f = 10 Hz f = 100 Hz f = 1 kHz f = 10 kHz 0.1 Hz to 10 Hz Bandwidth
10 5.2
1
AD8510/AD8512 only.
Rev. E | Page 3 of 20
AD8510/AD8512/AD8513
ELECTRICAL CHARACTERISTICS
@ VS = 15 V, VCM = 0 V, TA = 25C, unless otherwise noted. Table 2.
Parameter INPUT CHARACTERISTICS Offset Voltage (B Grade)1 Symbol VOS -40C < TA < +125C Offset Voltage (A Grade) Input Bias Current VOS -40C < TA < +125C IB -40C < TA < +85C -40C < TA < +125C Input Offset Current IOS -40C < TA < +85C -40C < TA < +125C Input Capacitance Differential Common-Mode Input Voltage Range Common-Mode Rejection Ratio Large Signal Voltage Gain Offset Voltage Drift (B Grade)1 Offset Voltage Drift (A Grade) OUTPUT CHARACTERISTICS Output Voltage High Output Voltage Low Output Voltage High Output Voltage Low Output Voltage High Output Voltage Low Output Current POWER SUPPLY Power Supply Rejection Ratio Supply Current/Amplifier AD8510/AD8512/AD8513 AD8510/AD8512 AD8513 DYNAMIC PERFORMANCE Slew Rate Gain Bandwidth Product Settling Time THD + Noise Phase Margin 12.5 11.5 CMRR AVO VOS/T VOS/T VOH VOL VOH VOL VOH VOL IOUT PSRR ISY VS = 4.5 V to 18 V VO = 0 V -40C < TA < +125C -40C < TA < +125C SR GBP tS THD + N O RL = 2 k To 0.1%, 0 V to 10 V Step, G = +1 To 0.01%, 0 V to 10 V Step, G = +1 1 kHz, G = +1, RL = 2 k 86 2.2 2.5 2.6 3.0 RL = 10 k -40C < TA < +125C RL = 2 k -40C < TA < +125C RL = 600 , TA = 25C -40C < TA < +125C RL = 600 , TA = 25C -40C < TA < +125C +14.0 +13.8 +13.5 11.4 VCM = -12.5 V to +12.5 V VO = -13.5 V to +13.5 V RL = 2 k, VCM = 0 V -13.5 86 115 +13.0 108 196 1.0 1.7 +14.2 -14.9 +14.1 -14.8 +13.9 -14.3 70 5 12 6 25 0.1 Conditions Min Typ 0.08 Max 0.4 0.8 1.0 1.8 80 0.7 10 75 0.3 0.5 Unit mV mV mV mV pA nA nA pA nA nA pF pF V dB V/mV V/C V/C V V V V V V V V mA dB mA mA mA V/s MHz s s % Degrees
-14.6 -14.5
-13.8 -12.1
20 8 0.5 0.9 0.0005 52
Rev. E | Page 4 of 20
AD8510/AD8512/AD8513
Parameter NOISE PERFORMANCE Voltage Noise Density Symbol en Conditions f = 10 Hz f = 100 Hz f = 1 kHz f = 10 kHz 0.1 Hz to 10 Hz Bandwidth Min Typ 34 12 8.0 7.6 2.4 Max Unit nV/Hz nV/Hz nV/Hz nV/Hz V p-p
10 5.2
Peak-to-Peak Voltage Noise
en p-p
1
AD8510/AD8512 only.
Rev. E | Page 5 of 20
AD8510/AD8512/AD8513 ABSOLUTE MAXIMUM RATINGS
Table 3. AD8510/AD8512/AD8513 Stress Ratings1
Parameter Supply Voltage Input Voltage Output Short-Circuit Duration to GND Storage Temperature Range R, RM Packages Operating Temperature Range Junction Temperature Range R, RM Packages Lead Temperature Range (Soldering, 10 sec) Electrostatic Discharge (HBM) Rating 18 V VS Observe Derating Curves -65C to +150C -40C to +125C -65C to +150C 300C 2000 V
Table 4. Thermal Resistance
Package Type 8-Lead MSOP (RM) 8-Lead SOIC (R) 14-Lead SOIC (R) 14-Lead TSSOP (RU) JA2 210 158 120 180 JC 45 43 36 35 Unit C/W C/W C/W C/W
1
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those listed in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. 2 JA is specified for worst-case conditions, i.e., JA is specified for device soldered in circuit board for surface-mount packages.
ESD 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 this product features 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 | Page 6 of 20
AD8510/AD8512/AD8513 TYPICAL PERFORMANCE CHARACTERISTICS
120 VSY = 15V TA = 25C 100 INPUT BIAS CURRENT (pA)
10k 100k VSY = 5V, 15V
NUMBER OF AMPLIFIERS
80
1k
60
100
40
02729-D-007
0 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 INPUT OFFSET VOLTAGE (mV)
1 -40
-25 -10
5
20 35 50 65 TEMPERATURE (C)
80
95
110 125
Figure 7. Input Offset Voltage Distribution
30 VSY = 15V B GRADE 25
Figure 10. Input Bias Current vs. Temperature
1000
INPUT OFFSET CURRENT (pA)
NUMBER OF AMPLIFIERS
100 15V 10 5V
20
15
10
1
02729-D-011
0 0 1 2 3 TCVOS (V/C) 4 5 6
02729-D-008
5
0.1 -40
-25 -10
5
20 35 50 65 TEMPERATURE (C)
80
95
110 125
Figure 8. AD8510/AD8512 TCVOS Distribution
30 VSY = 15V A GRADE 25
Figure 11. Input Offset Current vs. Temperature
40 TA = 25C 35 30 25 20 15 10 5 0
02729-D-012
NUMBER OF AMPLIFIERS
20
15
10
0 0 1 2 3 TCVOS (V/C) 4 5 6
02729-D-009
5
INPUT BIAS CURRENT (pA)
8
13
18 23 SUPPLY VOLTAGE (V+ - V- )
28
30
Figure 9. AD8510/AD8512 TCVOS Distribution
Figure 12. Input Bias Current vs. Supply Voltage
Rev. E | Page 7 of 20
02729-D-010
20
10
AD8510/AD8512/AD8513
2.0
SUPPLY CURRENT PER AMPLIFIER (mA)
2.8
1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2
TA = 25C
TA = 25C 2.6 2.4
SUPPLY CURRENT (mA)
2.2 2.0 1.8 1.6 1.4
02729-D-013
1.1 1.0 8 13 18 23 SUPPLY VOLTAGE (V+ - V-) 28
1.2 1.0 8 13 18 23 SUPPLY VOLTAGE (V+ - V-) 28
30
33
Figure 13. AD8512 Supply Current per Amplifier vs. Supply Voltage
16 VOL 14 VOH
OUTPUT VOLTAGE (V)
Figure 16. AD8510 Supply Current vs. Supply Voltage
70 315 VSY = 15V RL = 2.5k CSCOPE = 20pF M = 52 DEGREES 270 225 180 135 90 45 0 -45 -90 100k 1M FREQUENCY (Hz) 10M -135 50M
02729-D-017
VSY = 15V
60 50 40
12 10 8 6
VOL VSY = 5V
GAIN (dB)
30 20 10 0
4 2 0 0 10 20 30 40 50 LOAD CURRENT (mA) 60 70
02729-D-014
VOH
-10 -20 -30 10k
80
Figure 14. AD8510/AD8512 Output Voltage vs. Load Current
2.50 2.50
Figure 17. Open-Loop Gain and Phase vs. Frequency
SUPPLY CURRENT AMPLIFIER (mA)
SUPPLY CURRENT AMPLIFIER (mA)
2.25
2.25
15V
2.00
15V
2.00
5V
1.75 5V 1.50
1.75
1.50
02729-D-015
1.00 -40 -25
-10
5
20 65 35 50 TEMPERATURE (C)
80
95
110 125
1.00 -40 -25
-10
5
20 65 35 50 TEMPERATURE (C)
80
95
110 125
Figure 15. AD8512 Supply Current per Amplifier vs. Temperature
Figure 18. AD8510 Supply Current vs. Temperature
Rev. E | Page 8 of 20
02729-D-018
1.25
1.25
PHASE (Degrees)
02729-D-016
AD8510/AD8512/AD8513
70 60 50 VSY = 15V, 5V 300 270 240 VSY = 15V VIN = 50mV
CLOSED-LOOP GAIN (dB)
OUTPUT IMPEDANCE ()
40 AV = 100 30 20 AV = 10 10 0 AV = 1 -10
02729-D-019
210 180 150 120 90 60 30 0 100 1k 10k 1M 100k FREQUENCY (Hz) 10M 100M AV = 100 AV = 10 AV = 1
-20 -30 1k 10k 100k 1M FREQUENCY (Hz) 10M
50M
Figure 19. Closed-Loop Gain vs. Frequency
120 VSY = 15V
VOLTAGE NOISE DENSITY (nV Hz)
32
Figure 22. Output Impedance vs. Frequency
VSY = 5V TO 15V 28 24 20 16 12 8 4 0 0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 FREQUENCY (kHz)
02729-D-023
100
80
CMRR (dB)
60
40
0 100
1k
100k 1M 10k FREQUENCY (Hz)
10M
100M
02729-D-020
20
25.0
Figure 20. CMRR vs. Frequency
120 VSY = 5V, 15V 100
Figure 23. Voltage Noise Density
VSY = 15V
-PSRR
PSRR (dB)
60
40 +PSRR 20
02729-D-021
VOLTAGE (1V/DIV)
80
0 -20 100
1k
10k 100k 1M FREQUENCY (Hz)
10M
100M
TIME (1s/DIV)
Figure 21. PSRR vs. Frequency
Figure 24. 0.1 Hz to 10 Hz Input Voltage Noise
Rev. E | Page 9 of 20
02729-D-024
02729-D-022
AD8510/AD8512/AD8513
280 VSY = 5V TO 15V 245
90 80 70
OVERSHOOT (%)
VSY = 15V RL = 2k
VOLTAGE NOISE DENSITY (nV Hz)
210 175 140 105 70
02729-D-025
60 50 40 30 20 10 0 1 10 100 CAPACITANCE (pF) 1k
02729-D-028
+OS -OS
35 0 0 10 20 30 40 50 60 70 80 90 FREQUENCY (Hz)
100
10k
Figure 25. Voltage Noise Density vs. Frequency
70 VSY = 15V RL = 2k CL = 100pF AV = 1 60 50 40
Figure 28. Small Signal Overshoot vs. Load Capacitance
315 VSY = 5V RL = 2.5k 270 CSCOPE = 20pF M = 44.5 DEGREES 225
VOLTAGE (5V/DIV)
GAIN (dB)
30 20 10 0
135 90 45 0 -45 -90 100k 1M FREQUENCY (Hz) 10M
02729-D-026
-10 -20 -30 10k
-135 50M
TIME (1s/DIV)
Figure 26. Large Signal Transient Response
VSY = 15V RL = 2k CL = 100pF AV = 1
VOLTAGE (50mV/DIV)
120
Figure 29. Open-Loop Gain and Phase vs. Frequency
VSY = 5V 100
80
CMRR (dB)
60
40
02729-D-027
TIME (100ns/DIV)
0 100
1k
100k 1M 10k FREQUENCY (Hz)
10M
100M
Figure 27. Small Signal Transient Response Figure 30. CMRR vs. Frequency
Rev. E | Page 10 of 20
02729-D-030
20
02729-D-029
PHASE (Degrees)
180
AD8510/AD8512/AD8513
300 270 240
OUTPUT IMPEDANCE ()
VSY = 5V VIN = 50mV
210 180 150 120
AV = 100
VOLTAGE (50mV/DIV)
02729-D-031
VSY = 5V RL = 2k CL = 100pF AV = 1
AV = 1
90 60
AV = 10
0 100
1k
10k
100k 1M FREQUENCY (Hz)
10M
100M
TIME (100ns/DIV)
Figure 31. Output Impedance vs. Frequency
VSY = 5V 100 90 80
Figure 34. Small Signal Transient Response
VSY = 5V RL = 2k
VOLTAGE (1V/DIV)
OVERSHOOT (%)
70 60 50 -OS 40 30 +OS
02729-D-032
20 10 0 1 10 100 CAPACITANCE (pF) 1k
02729-D-035
TIME (1s/DIV)
10k
Figure 32. 0.1 Hz to 10 Hz Input Voltage Noise
VSY = 5V RL = 2k CL = 100pF AV = 1
Number of Amplifiers VOLTAGE (2V/DIV)
Figure 35. Small Signal Overshoot vs. Load Capacitance
100 VS = 15V 90 80 70 60 50 40 30 20 10 0 0 1 2 3 TCVOS (V/C) 4 5 6
02729-D-036
TIME (1s/DIV)
Figure 33. Large Signal Transient Response
02729-D-033
Figure 36. AD8513 TCVOS Distribution
Rev. E | Page 11 of 20
02729-D-034
30
AD8510/AD8512/AD8513
120 VS = 5V
14 16 VOL VOH VSY = 15V
100
80
OUTPUT VOLTAGE (V)
12 10 8 6 VOL 4 VOH
02729-D-039
Number of Amplifiers
60
40
VSY = 5V
02729-D-037
20
2 0 0 10 20 30 40 50 60 70 LOAD CURRENT (mA)
0 0 1 2 3 TCVOS (V/C) 4 5 6
80
Figure 37. AD8513 TCVOS Distribution
2.5
SUPPLY CURRENT PER AMPLIFIER (mA)
Figure 39. AD8513 Output Voltage vs. Load Current
3.0
2.4 2.3
SUPPLY CURRENT (mA)
TA = 25C
2.5 15V 2.0 5V 1.5
2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 8 13 18 23 28 SUPPLY VOLTAGE (V+ - V-)
02729-D-038
1.0
33
0 -40
-25
-10
5
20
35
50
65
80
95
110
125
TEMPERATURE (C)
Figure 38. AD8513 Supply Current vs. Supply Voltage
Figure 40. AD8513 Supply Current vs. Temperature
Rev. E | Page 12 of 20
02729-D-040
0.5
AD8510/AD8512/AD8513 GENERAL APPLICATION INFORMATION
INPUT OVERVOLTAGE PROTECTION
The AD8510/AD8512/AD8513 have internal protective circuitry that allows voltages as high as 0.7 V beyond the supplies to be applied at the input of either terminal without causing damage. For higher input voltages, a series resistor is necessary to limit the input current. The resistor value can be determined from the formula
V IN - VS RS 5mA
02729-D-056
0.01 VSY = 5V RL = 100k BW = 22kHz
DISTORTION (%)
0.001
With a very low offset current of <0.5 nA up to 125C, higher resistor values can be used in series with the inputs. A 5 k resistor will protect the inputs to voltages as high as 25 V beyond the supplies and will add less than 10 V to the offset.
0.0001 20
100
1k FREQUENCY (Hz)
20k
Figure 42. THD + N vs. Frequency
OUTPUT PHASE REVERSAL
Phase reversal is a change of polarity in the transfer function of the amplifier. This can occur when the voltage applied at the input of an amplifier exceeds the maximum common-mode voltage. Phase reversal can cause permanent damage to the device and may result in system lockups. The AD8510/AD8512/AD8513 do not exhibit phase reversal when input voltages are beyond the supplies.
VSY = 5V AV = 1 RL = 10k
TOTAL NOISE INCLUDING SOURCE RESISTORS
The low input current noise and input bias current of the AD8510/AD8512/AD8513 make them the ideal amplifiers for circuits with substantial input source resistance. Input offset voltage increases by less than 15 nV per 500 of source resistance at room temperature. The total noise density of the circuit is
e nTOTAL = e n 2 + (i n R S )2 + 4kTR S
VOLTAGE (2V/DIV)
VOUT
where: en is the input voltage noise density of the parts. in is the input current noise density of the parts. RS is the source resistance at the noninverting terminal. k is Boltzman's constant (1.38 x 10-23 J/K). T is the ambient temperature in Kelvin (T = 273 + C). For RS < 3.9 k, en dominates and enTOTAL en. The current noise of the AD8510/AD8512/AD8513 is so low that its total density does not become a significant term unless RS is greater than 165 M, an impractical value for most applications. The total equivalent rms noise over a specific bandwidth is expressed as
VIN
TIME (20s/DIV)
Figure 41. No Phase Reversal
02729-D-057
THD + NOISE
The AD8510/AD8512/AD8513 have low total harmonic distortion and excellent gain linearity, making these amplifiers a great choice for precision circuits with high closed-loop gain, and for audio application circuits. Figure 42 shows that the AD8510/ AD8512/AD8513 have approximately 0.0005% of total distortion when configured in positive unity gain (the worst case) and driving a 100 k load.
enTOTAL = enTOTAL BW
where BW is the bandwidth in Hertz. Note that the above analysis is valid for frequencies larger than 150 Hz and assumes flat noise above 10 kHz. For lower frequencies, flicker noise (1/f) must be considered.
Rev. E | Page 13 of 20
AD8510/AD8512/AD8513
SETTLING TIME
Settling time is the time it takes the output of the amplifier to reach and remain within a percentage of its final value after a pulse has been applied at the input. The AD8510/AD8512/ AD8513 settle to within 0.01% in less than 900 ns with a step of 0 V to 10 V in unity gain. This makes the each of the parts an excellent choice as a buffer at the output of DACs whose settling time is typically less than 1 s. In addition to their fast settling time and fast slew rate, the AD8510/AD8512/AD8513's low offset voltage drift and input offset current maintain full accuracy of 12-bit converters over the entire operating temperature range.
OUTPUT
+15V
VSY = 15V AV = -100 RL = 10k
VOLTAGE
0V
INPUT
0V -200mV
02729-D-054
TIME (2s/DIV)
OVERLOAD RECOVERY TIME
Overload recovery, also known as overdrive recovery, is the time it takes the output of an amplifier to recover from a saturated condition to its linear region. This recovery time is particularly important in applications where the amplifier must amplify small signals in the presence of large transient voltages. Figure 43 shows the positive overload recovery of the AD8510/AD8512/AD8513. The output recovers in approximately 200 ns from a saturated condition.
VSY = 15V VIN = 200mV AV = -100 RL = 10k
Figure 44. Negative Overload Recovery
CAPACITIVE LOAD DRIVE
The AD8510/AD8512/AD8513 are unconditionally stable at all gains in inverting and noninverting configurations. They are capable of driving up to 1000 pF of capacitive loads without oscillation in unity gain, the worst-case configuration. However, as with most amplifiers, driving larger capacitive loads in a unity gain configuration may cause excessive overshoot and ringing or even oscillation. A simple snubber network reduces the amount of overshoot and ringing significantly. The advantage of this configuration is that the output swing of the amplifier is not reduced, because RS is outside the feedback loop.
V+
OUTPUT VOLTAGE
0V
-15V
7
INPUT
200mV 0V
02729-D-053
AD8510
200mV
4
6
VOUT RS CS CL
02729-D-055
V-
TIME (2s/DIV)
Figure 45. Snubber Network Configuration
Figure 43. Positive Overload Recovery
The negative overdrive recovery time shown in Figure 44 is less than 200 ns. In addition to the fast recovery time, the AD8510/AD8512/ AD8513 show excellent symmetry of the positive and negative recovery times. This is an important feature for transient signal rectification, because the output signal is kept equally undistorted throughout any given period.
Figure 46 shows a scope photograph of the output of the AD8510/AD8512/AD8513 in response to a 400 mV pulse. The circuit is configured in positive unity gain (worst-case) with a load experience of 500 pF.
Rev. E | Page 14 of 20
AD8510/AD8512/AD8513
VSY = 15V CL = 500pF RL =10k
OPEN-LOOP GAIN AND PHASE RESPONSE
In addition to their impressive low noise, low offset voltage, and offset current, the AD8510/AD8512/AD8513 have excellent loop gain and phase response even when driving large resistive and capacitive loads. They were compared to the OPA2132 under the same conditions. With a 2.5 k load at the output, the AD8510/AD8512/AD8513 have more than 8 MHz of bandwidth and a phase margin of more than 52. The OPA2132, on the other hand, has only 4.5 MHz of bandwidth and 28 of phase margin under the same test conditions. Even with a 1 nF capacitive load in parallel with the 2 k load at the output, the AD8510/AD8512/AD8513 show much better response than the OPA2132, whose phase margin is degraded to less than 0, indicating oscillation.
70 60 50 VSY = 15V RL = 2.5k CL = 0 315 270 225 190 135 90 45 0 -45 -90 100k 1M FREQUENCY (Hz) 10M -135 50M
02729-D-043
02729-D-044
VOLTAGE (200mV/DIV)
TIME (1s/DIV)
Figure 46. Capacitive Load Drive without Snubber
When the snubber circuit is used, the overshoot is reduced from 55% to less than 3% with the same load capacitance. Ringing is virtually eliminated, as shown in Figure 47.
02729-D-041
GAIN (dB)
30 20 10 0
VOLTAGE (200mV/DIV)
-10 -20 -30 10k
02729-D-042
Figure 48. Frequency Response of the AD8510/AD8512/AD8513
70 315 VSY = 15V RL = 2.5k CL = 0 270 225 190 135 90 45 0 -45 -90 100k 1M FREQUENCY (Hz) 10M -135 50M
TIME (1s/DIV)
Figure 47. Capacitive Load with Snubber Network
60 50
GAIN (dB)
30 20 10 0
Table 5. Optimum Values for Capacitive Loads
CLOAD 500 pF 2 nF 5 nF RS () 100 70 60 CS 1 nF 100 pF 300 pF
-10 -20 -30 10k
Figure 49. Frequency Response of the OPA2132
Rev. E | Page 15 of 20
PHASE (Degrees)
Optimum values for RS and CS depend on the load capacitance and input stray capacitance and are determined empirically. Table 5 shows a few values that can be used as starting points.
40
PHASE (Degrees)
VSY = 15V RL =10k CL = 500pF RS =100 CS =1nF
40
AD8510/AD8512/AD8513
PRECISION RECTIFIERS
Rectifying circuits are used in a multitude of applications. One of the most popular uses is in the design of regulated power supplies, where a rectifier circuit is used to convert an input sinusoid to a unipolar output voltage. There are some potential problems for amplifiers used in this manner. When the input voltage (VIN) is negative, the output is zero. The magnitude of VIN is doubled at the inputs of the op amp. This voltage can exceed the power supply voltage, which would damage some amplifiers permanently. The op amp must come out of saturation when VIN is negative. This delays the output signal because the amplifier requires time to enter its linear region. The AD8510/AD8512/AD8513 have a very fast overdrive recovery time, which makes them great choices for the rectification of transient signals. The symmetry of the positive and negative recovery times is also important in keeping the output signal undistorted. Figure 50 shows the test circuit of the rectifier. The first stage of the circuit is a half-wave rectifier. When the sine wave applied at the input is positive, the output follows the input response. During the negative cycle of the input, the output tries to swing negative to follow the input, but the power supply restrains it to zero. In a similar fashion, the second stage is a follower during the positive cycle of the sine wave and an inverter during the negative cycle.
R2 10k R3 10k
VOLTAGE (1V/DIV)
TIME (1ms/DIV)
Figure 51. Half-Wave Rectifier Signal (Out A)
VOLTAGE (1V/DIV)
TIME (1ms/DIV)
Figure 52. Full-Wave Rectifier Signal (Out B)
5V VIN 3V p-p R1 1k
2 6 3
2/2
4 7
1/2
8 1 5
AD8512
8
AD8512
4
OUT B (HALF WAVE)
5V OUT A (HALF WAVE)
Figure 50. Half-Wave and Full-Wave Rectifier
Rev. E | Page 16 of 20
02729-D-045
02729-D-047
02729-D-046
AD8510/AD8512/AD8513
I-V CONVERSION APPLICATIONS
Photodiode Circuits
Common applications for I-V conversion include photodiode circuits, where the amplifier is used to convert a current emitted by a diode placed at the positive input terminal into an output voltage. The AD8510/AD8512/AD8513's low input bias current, wide bandwidth, and low noise make them each an excellent choice for various photodiode applications, including fax machines, fiber optic controls, motion sensors, and bar code readers. The circuit shown in Figure 53 uses a silicon diode with zero bias voltage. This is known as a Photovoltaic Mode; this configuration limits the overall noise and is suitable for instrumentation applications.
Cf
includes external parasitic capacitance. Ct creates a pole in the frequency response, which may lead to an unstable system. To ensure stability and optimize the bandwidth of the signal, a capacitor is placed in the feedback loop of the circuit shown in Figure 53. It creates a zero and yields a bandwidth whose corner frequency is 1/(2(R2Cf)). The value of R2 can be determined by the ratio V/ID, where V is the desired output voltage of the op amp and ID is the diode current. For example, if ID is 100 A and a 10 V output voltage is desired, R2 should be 100 k. Rd is a junction resistance that drops typically by a factor of 2 for every 10C increase in temperature. A typical value for Rd is 1000 M. Since Rd >> R2, the circuit behavior is not impacted by the effect of the junction resistance. The maximum signal bandwidth is
f MAX = ft 2R2Ct
R2
VEE
where ft is the unity gain frequency of the amplifier.
2 4
AD8510
Rd Ct
3 7
6
Using the parameters above, Cf 1 pF, which yields a signal bandwidth of about 2.6 MHz.
02729-D-048
Cf =
VCC
Ct 2R2 ft
Figure 53. Equivalent Preamplifier Photodiode Circuit
where ft is the unity gain frequency of the op amp, achieves a phase margin, m, of approximately 45. A higher phase margin can be obtained by increasing the value of Cf. Setting Cf to twice the previous value yields approximately m = 65 and a maximally flat frequency response, but reduces the maximum signal bandwidth by 50%.
A larger signal bandwidth can be attained at the expense of additional output noise. The total input capacitance (Ct) consists of the sum of the diode capacitance (typically 3 pF to 4 pF) and the amplifier's input capacitance (12 pF), which
Rev. E | Page 17 of 20
AD8510/AD8512/AD8513
Signal Transmission Applications
One popular signal transmission method uses pulse-width modulation. High data rates may require a fast comparator rather than an op amp. However, the need for sharp and undistorted signals may favor using a linear amplifier. The AD8510/AD8512/AD8513 make excellent voltage comparators. In addition to a high slew rate, the AD8510/ AD8512/AD8513 have a very fast saturation recovery time. In the absence of feedback, the amplifiers are in open-loop mode (very high gain). In this mode of operation, they spend much of their time in saturation. The circuit in Figure 54 compares two signals of different frequencies, namely a 100 Hz sine wave and a 1 kHz triangular wave. Figure 56 shows a scope photograph of the output waveform. A pull-up resistor (typically 5 k) may be connected from the output to VCC if the output voltage needs to reach the positive rail. The trade-off is that power consumption will be higher.
+15V
VOLTAGE (5V/DIV)
TIME (2ms/DIV)
Figure 56. Pulse-Width Modulation
Crosstalk
Crosstalk, also known as channel separation, is a measure of signal feedthrough from one channel to the other on the same IC. The AD8512/AD8513 have a channel separation better than -90 dB for frequencies up to 10 kHz, and better than -50 dB for frequencies up to 10 MHz. Figure 57 shows the typical channel separation behavior between amplifier A (driving amplifier), with respect to amplifiers B, C, and D.
0
3
7
6
VOUT
2
V1
4
-20
02729-D-049
CHANNEL SEPARATION (dB)
-15V
V2
-40 -60 -80 -100 -120 -140 CH-D
02729-D-051
CH-B CH-C
Figure 54. Pulse-Width Modulator
VOUT 20k +VS 2 18V p-p 3 VIN CROSSTALK = 20 LOG 5k VOUT 10VIN 5k 4 -VS
02729-D-052
2.2k
8
6 1 7 5
-160 100
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 57. Channel Separation
Figure 55. Crosstalk Test Circuit
Rev. E | Page 18 of 20
02729-D-050
10M
AD8510/AD8512/AD8513 OUTLINE DIMENSIONS
5.00 (0.1968) 4.80 (0.1890)
8 5 4
5.10 5.00 4.90
4.00 (0.1574) 3.80 (0.1497) 1
6.20 (0.2440) 5.80 (0.2284)
4.50 4.40 4.30
14
8
1.27 (0.0500) BSC 0.25 (0.0098) 0.10 (0.0040)
1.75 (0.0688) 1.35 (0.0532)
0.50 (0.0196) x 45 0.25 (0.0099)
6.40 BSC
1 7
PIN 1
0.51 (0.0201) COPLANARITY SEATING 0.31 (0.0122) 0.10 PLANE
8 0.25 (0.0098) 0 1.27 (0.0500) 0.40 (0.0157) 0.17 (0.0067)
1.05 1.00 0.80
0.65 BSC 1.20 MAX 0.15 0.05 0.30 0.19 0.20 0.09 8 0 0.75 0.60 0.45
COMPLIANT TO JEDEC STANDARDS MS-012AA CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN
SEATING COPLANARITY PLANE 0.10
COMPLIANT TO JEDEC STANDARDS MO-153AB-1
Figure 58. 8-Lead Standard Small Outline Package [SOIC] Narrow Body (R-8) Dimensions shown in millimeters and (inches)
Figure 60. 14-Lead Thin Shrink Small Outline Package [TSSOP] (RU-14) Dimensions show in millimeters
3.00 BSC
8.75 (0.3445) 8.55 (0.3366)
5
8
3.00 BSC
4
4.90 BSC
4.00 (0.1575) 3.80 (0.1496)
14 1
8 7
6.20 (0.2441) 5.80 (0.2283)
PIN 1 0.65 BSC 1.10 MAX 8 0 0.80 0.60 0.40
0.25 (0.0098) 0.10 (0.0039) COPLANARITY 0.10
1.27 (0.0500) BSC
1.75 (0.0689) 1.35 (0.0531)
0.50 (0.0197) x 45 0.25 (0.0098)
0.15 0.00 0.38 0.22 COPLANARITY 0.10
0.51 (0.0201) 0.31 (0.0122)
SEATING PLANE
0.23 0.08 SEATING PLANE
8 0.25 (0.0098) 0 1.27 (0.0500) 0.40 (0.0157) 0.17 (0.0067)
COMPLIANT TO JEDEC STANDARDS MO-187AA
COMPLIANT TO JEDEC STANDARDS MS-012AB CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN
Figure 59. 8-Lead Mini Small Outline Package [MSOP] (RM-8) Dimensions shown in millimeters
Figure 61. 14-Lead Standard Small Outline Package [SOIC] Narrow Body (R-14) Dimensions shown in millimeters and (inches)
Rev. E | Page 19 of 20
AD8510/AD8512/AD8513
ORDERING GUIDE
Model AD8510ARM-REEL AD8510ARM-R2 AD8510AR AD8510AR-REEL AD8510AR-REEL7 AD8510ARZ1 AD8510ARZ-REEL1 AD8510ARZ-REEL71 AD8510BR AD8510BR-REEL AD8510BR-REEL7 AD8512ARM-REEL AD8512ARM-R2 AD8512ARMZ-REEL1 AD8512ARMZ-R21 AD8512AR AD8512AR-REEL AD8512AR-REEL7 AD8512ARZ1 AD8512ARZ-REEL1 AD8512ARZ-REEL71 AD8512BR AD8512BR-REEL AD8512BR-REEL7 AD8513AR AD8513AR-REEL AD8513AR-REEL7 AD8513ARU AD8513ARU-REEL Temperature Range -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C -40C to +125C Package Description 8-Lead MSOP 8-Lead MSOP 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 8-Lead SOIC 14-Lead SOIC 14-Lead SOIC 14-Lead SOIC 14-Lead TSSOP 14-Lead TSSOP Package Option RM-8 RM-8 R-8 R-8 R-8 R-8 R-8 R-8 R-8 R-8 R-8 RM-8 RM-8 RM-8 RM-8 R-8 R-8 R-8 R-8 R-8 R-8 R-8 R-8 R-8 R-14 R-14 R-14 RU-14 RU-14 Branding Information B7A B7A
B8A B8A B8A B8A
1
Z = Pb-free part.
(c) 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C02729-0-6/04(E)
Rev. E | Page 20 of 20

▲Up To Search▲

Price & Availability of AD8510BR

	To Download AD8510BR Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .