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ANALOG DEVICES AD8610/AD8620 Guide

1. 600 18 16 gt 400 g 2 ul O ui L 200 12 5 a z o z 10 lt gt 0 lt w ja m 8 tr tc E 5 200 6 E z 2 2 2 4 2 400 2 0 600 0 250 150 50 50 150 250 40 129 250 150 50 50 150 250 INPUT OFFSET VOLTAGE pV H INPUT OFFSET VOLTAGE p V TPC 1 Input Offset Voltage at 13 V TPC 2 Input Offset Voltage vs TPC 3 Input Offset Voltage at 5 V Temperature at 13 V 300 Amplifiers 600 3 6 Vs 13V E 3 4 gt 400 4 2 a 32 Ir E a 3 0 al a a 2 3 i 7 m 2 6 m 5 aw 2 5 5 amp 24 a z Z 400 ill i 600 2 0 40 25 85 125 0 02 06 10 14 18 22 26 10 10 TEMPERATURE TcVos uV C COMMON MODE VOLTAGE V TPC 4 Input Offset Voltage vs TPC 5 Input Offset Voltage Drift TPC 6 Input Bias Current vs Temperature at 5 V 300 Amplifiers Common Mode Voltage 3 0 3 05 2 65 B Vs 13V Vs 5V 2 60 p 2 5 NT P E E 2 55 20 E E 2 2 2 85 2 ul 2 50 a g 1 5 2 2 o o 2 45 gt x 2 75 x 1 0 a o 2 a 5 2 40 a 2 65 K 0 2 55 2 30 012345 6 7 8 9 10 111213 40 25 85 125 40 25 85 125 SUPPLY VOLTAGE V TEMPERATURE C TEMPERATURE C TPC 7 Supply Current vs TPC 8 Supply Current vs TPC 9
2. ELE ad Ge wae dE Fa Re an 9 Add Channel Separation Grape AUD ea EUR et aec a Od e eR efe deua Ato eth wt UP xe a thet 9 Changes to Figure 26 0 cist ee EE TERR Ee Rd erc CPP PURI Pere e Stes Race de eae Mee ERR Va ets 15 Addition of High Speed Low Noise Differential Driver section 16 Addition of Figure 30 iua eere gerbe rre p HER Ree e ret Repo e aod s bed o Wh UE QUA ep prd p MERE pret es 16 18 REV D 19 d v0 2 0 0 209 20
3. Figure 6 Capacitive Load Drive Test Circuit VOLTAGE 50mV DIV TIME 20ps DIV Figure 7 OPA627 Capacitive Load Drive Ay 2 Vg 5V RL 10kO CL 2pF VOLTAGE 50mV DIV TIME 20ps DIV Figure 8 AD8610 AD8620 Capacitive Load Drive Ay 2 Slew Rate Unity Gain Inverting vs Noninverting Amplifiers generally have a faster slew rate in an inverting unity gain configuration due to the absence of the differential input capacitance Figures 9 through 12 show the performance of the AD8610 configured in a gain of 1 compared to the OPA627 The AD8610 slew rate is more symmetrical and both the positive and negative transitions are much cleaner than in the OPA627 REV D AD8610 AD8620 Vs 13 RL 200 G 1 2 E 8 8 2 SR 54V p s gt 9 5 g g TIME 400ns DIV TIME 400ns DIV Figure 9 SR of AD8610 AD8620 in Unity Gain of 1 Figure 12 SR of OPA627 in Unity Gain of 1 The AD8610 has a very fast slew rate of 60 V s even when config Vg 13V ured in a noninverting gain of 1 This is the toughest condition to RL 2k impose on any amplifier since the input common mode capacitance Er of the ampl
4. 2004 Analog Devices Inc All rights reserved AD86 1 0 AD8620 SPEC CATI 0 NS Vs 5 0 V Ven 0 V T 25 C unless otherwise noted Parameter Symbol Conditions Min Typ Max Unit INPUT CHARACTERISTICS Offset Voltage AD8610B Vos 45 100 uV 40 C lt Ta lt 125 C 80 200 uV Offset Voltage AD8620B Vos 45 150 uV 40 C lt Ty lt 125 C 80 300 uV Offset Voltage AD8610A AD8620A Vos 85 250 uV 25 C lt Ta lt 125 C 90 350 uV 40 C lt T4 lt 125 C 150 850 uV Input Bias Current Is 10 2 10 pA 40 C lt T4 lt 85 C 250 130 250 pA 40 C lt T4 lt 125 2 5 15 2 5 Input Offset Current Ios 10 1 10 40 C lt Ta lt 85 75 20 75 40 lt T4 lt 125 150 40 150 pA Input Voltage Range 2 3 V Common Mode Rejection Ratio CMRR Vom 2 5 V to 1 5 V 90 95 dB Large Signal Voltage Gain Avo Rr 1 kQ Vo 3 V to 3 V 100 180 V mV Offset Voltage Drift AD8610B AVos AT 40 lt T4 lt 125 C 0 5 1 Offset Voltage Drift AD8620B AVos AT 40 lt T4 lt 125 0 5 1 5 Offset Voltage Drift AD8610A AD8620A AVos AT 40 lt T4 lt 125 C 0 8 3 5 OUTPUT CHARACTERISTICS Output Voltage High Rr 1 kQ 40 C lt Ta lt 125 3 8 4 V Output Voltage Low Vor Rr 1 40 lt 125 C 4 3 8 V Output Current lour Vour gt 2 V 30 mA POWER SUPPLY Power
5. Butterworth low pass filter With the values as shown the corner frequency of the filter will be 1 MHz The wide bandwidth of the AD8610 AD8620 allows a corner frequency up to tens of megaHertz The following equations can be used for component selection R1 R2 User Selected Typical Values 10 kQ 100 kQ 1 414 Me 2x fourorr R1 rs 0 707 2 fourorr RI where C1 and C2 are in farads Figure 29 Second Order Low Pass Filter Table II Filter Types Type Sensitivity Overshoot Phase Amplitude Pass Band Butterworth Moderate Good Max Flat Chebyshev Good Moderate Nonlinear Equal Ripple Elliptical Best Poor Equal Ripple Bessel Thompson Poor Best Linear REV D 15 AD8610 AD8620 High Speed Low Noise Differential Driver The AD8620 is a perfect candidate as a low noise differential driver for many popular ADCs There are also other applications D m such as balanced lines that require differential drivers The circuit 500 of Figure 30 is a unique line driver widely used in industrial applica tions With 13 V supplies the line driver can deliver a differential signal of 23 V p p into a 1 kQ load The high slew rate and wide bandwidth of the AD8620 combine to yield a full power bandwidth of 145 kHz while the low noise front end produces a referred to 3 OF AD8620 input noise voltage spectral density of 6 nV VHz The design is a M transformerless balanced transmission system where output
6. Differential Input Voltage Supply Voltage 8 SOIC RN 158 45 C W Output Short Circuit Duration to GND Indefinite 5S Storage Temperature Range M RM Packages 65 to 150 i Operating Temperature Range AD8610 AD8620 40 C to 125 C Junction Temperature Range RM Packages 65 to 150 C Lead Temperature Range Soldering 10 sec 300 C 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 ORDERING GUIDE Temperature Package Package Model Range Description Option Branding AD8610AR 40 C to 125 C 8 Lead SOIC RN 8 AD8610AR REEL 40 C to 125 C 8 Lead SOIC RN 8 AD8610AR REEL7 40 C to 125 C 8 Lead SOIC RN 8 AD8610ARM REEL 40 C to 125 C 8 Lead MSOP RM 8 BOA AD8610ARM R2 40 C to 125 C 8 Lead MSOP RM 8 BOA AD8610ARZ 40 C to 125 8 Lead SOIC RN 8 AD8610ARZ REEL 40 C to 125 C 8 Lead SOIC RN 8 AD8610ARZ REEL7 40 C to 125 C 8 Lead SOIC RN 8 AD8610BR 40 C to 125 C 8 Lead SOIC RN 8 AD8610B
7. 10M 60M 40 25 85 125 FREQUENCY Hz FREQUENCY Hz TEMPERATURE TPC 19 PSRR vs Frequency at 13 V TPC 20 PSRR vs Frequency at 5 V TPC 21 PSRR vs Temperature 140 Vs 13V Vs 13V Vs 13V 5 120 Vin 300mV Vin 300mV Ay 100 Ay 100 deka gt 10kQ 100 5 a C OpF m go 5 S Vin 1 e g T ov 1 tc 1 gt 60 ViN 9 4 V 2 40 2 CH2 5V DIV OUT 9 20 1 10 100 1k 10k 100k 1M 10M 60M TIME 4us DIV TIME 4p s DIV FREQUENCY Hz TPC 22 CMRR vs Frequency TPC 23 Positive Overvoltage Recovery TPC 24 Negative Overvoltage Recovery 100 Vs 13 90 Vin 1 8nV z a i 80 gt t 2 70 E a g 60 g a E50 ul 3 g g 40 a z u 30 6 a 20 gt 10 TIME 1s DIV 0 1 10 100 1k 10k 100k 1M 1k 10k 100k 1 10M 100M FREQUENCY Hz FREQUENCY Hz TPC 25 0 1 Hz to 10 Hz Input Voltage TPC 26 Input Voltage Noise vs TPC 27 Zour vs Frequency Noise Frequency REV D 7 AD8610 AD8620 100 90 80 70 60 50 Zour Q 40 SMALL SIGNAL OVERSHOOT 1k 10k 100k 1M 10M FREQUENCY Hz TPC 28 Zour vs Frequency Vg 5V 2kQ Vin 100mV 1 10 100 ik CAPACITANCE pF 10k TPC 31 Small Signal Overshoot vs Load Capacitance VOLTAGE 5V
8. 2 0 5 0 0 001 0 01 0 1 1 10 ERROR BAND 5 0 500 1000 1500 2000 Figure 20 AD8610 Settling Time vs Error Band C pF Figure 23 OPA627 Settling Time vs Load Capacitance Output Current Capability The AD8610 can drive very heavy loads due to its high output current It is capable of sourcing or sinking 45 mA at 10 V output The short circuit current is quite high and the part is capable of sinking about 95 mA and sourcing over 60 mA while operating with REV D 13 AD8610 AD8620 supplies of 5 V Figures 24 and 25 compare the load current versus output voltage of AD8610 AD8620 and OPA627 10 DELTA FROM RESPECTIVE RAIL V 0 1 0 00001 0 0001 0 001 0 01 0 1 1 LOAD CURRENT A Figure 24 AD8610 Dropout from 13 V vs Load Current 10 gt E V cc gt 5 w VEE 5 n w tr z w 4 5 w a 0 1 0 00001 0 0001 0 001 0 01 0 1 1 LOAD CURRENT Figure 25 OPA627 Dropout from 15 V vs Load Current Although operating conditions imposed on the AD8610 13 V are less favorable than the OPA627 15 V it can be seen that the AD8610 has much better drive capability lower headroom to the supply for
9. DIV TIME 400ns DIV TPC 34 SR at G 1 3000 2500 2000 1000 TPC 29 Input Bias Current vs Temperature VOLTAGE 5V DIV VOLTAGE 5V DIV 25 85 125 TEMPERATURE C Vs 13V Vin 14V Ay 1 FREQ 0 5kHz TIME 400p s DIV TPC 32 No Phase Reversal Vs 13V Vin P p 20V Ay 1 RL 2kQ CL 20pF TIME 400ns DIV TPC 35 SR at G 1 Vs 13V 2kQ Vin 100mV p p SMALL SIGNAL OVERSHOOT CAPACITANCE pF ik TPC 30 Small Signal Overshoot vs Load Capacitance VOLTAGE 5V DIV Vs 13V Vin 20V Ay 1 2kQ CL 20pF TIME 1ps DIV TPC 33 Large Signal Response at G 1 z g gt 1 amp d gt Vs 131 Vin 20V 7 1 RL 2kO CL 20pF TIME 1 ps DIV TPC 36 Large Signal Response at G 1 REV D AD8610 AD8620 Vg 13V Vin p p 20V Ay 1 RL 2kQ 8 8 SR 50V us 8 E C 20pF Vs 13V 2 set 2 ViN
10. Hz Figure 18 AD8610 vs OPA627 THD Noise Vey 0 REV D AD8610 AD8620 0 1 1 2k Vey 13V 6000 1 0k E 800 Di ul 0 01 amp 600 2 lt 400 OPA627 200 0 001 0 10 100 1k 10k 20k 0 001 0 01 0 1 1 10 FREQUENCY Hz ERROR BAND Figure 19 THD Noise vs Frequency Figure 21 OPA627 Settling Time vs Error Band Noise vs Common Mode Voltage The AD8610 AD8620 maintains this fast settling when loaded AD8610 noise density varies only 10 over the input range as with large capacitive loads as shown in Figure 22 shown in Table I 3 0 Table I Noise vs Common Mode Voltage ERHOR BAND 50 01 2 5 Vom at F 1 KHz V Noise Reading nV VHz 10 7 21 2 20 5 6 89 0 6 73 515 5 6 41 10 7 21 H 10 o Settling Time T The AD8610 has a very fast settling time even to a very tight error band as be seen from Figure 20 The AD8610 is configured in an inverting gain of 1 with 2 input and feedback resistors 005 500 1000 1500 2000 The output is monitored with a 10 x 10 M 11 2 pF scope probe CL pF 12k Figure 22 AD8610 Settling Time vs Load Capacitance 3 0 E ERROR BAND 0 01 o 2 5 F 800 a 220 T 1 g 600 E 1 5 400 1 0 200
11. Vo2 Vo1 Vin common mode rejection of noise is of paramount importance v Like the transformer based design either output can be shorted o to ground for unbalanced line driver applications without changing Figure 30 Differential Driver the circuit gain of 1 This allows the design to be easily set to noninverting inverting or differential operation AD8610 w 509 16 REV D AD8610 AD8620 OUTLINE DIMENSIONS 8 Lead Mini Small Outline Package MSOP 8 Lead Standard Small Outline Package SOIC RM 8 Narrow Body Dimensions shown in millimeters R 8 Dimensions shown in millimeters and inches 5 00 0 1968 MED 0 1 sso AAAH BSC 4 00 0 1574 6 20 0 2440 3 80 0 1497 5 80 0 2284 28 1 27 0 0500 0 50 0 0196 5 BSC 1 75 0 0688 0 25 0 0099 0 25 0 0098 1 35 0 0532 E q E 0 10 0 0040 Y y H 0 80 N ol Lg 051 0 0201 1 o 1 27 0 0500 0 38 0 23 4 4 gt 0 60 COPLANARITY _ 0 31 0 0122 0 25 0 0098 0 1 27 0 0500 lle 0 23 d 0 10 0 40 0 0157 0 22 0 08 0 40 PLANE 0 17 0 0067 COPLANARITY SEATING 0 10 PLANE COMPLIANT TO JEDEC STANDARDS MS 012AA CONTROLLING DIMENSIONS ARE IN MILLIMETERS INCH DIMENSIONS COMPLIANT TO JEDEC STANDARDS MO 187AA IN PARENTHESES ARE ROUNDED OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN REV D 17 AD8610 AD8620 Revision Histo
12. a given load current Operating with Supplies Greater than 13 V The AD8610 maximum operating voltage is specified at 13 V When 13 V is not readily available an inexpensive LDO can provide 12 V from a nominal 15 V supply Input Offset Voltage Adjustment Offset of AD8610 is very small and normally does not require additional offset adjustment However the offset adjust pins can be used as shown in Figure 26 to further reduce the dc offset By using resistors in the range of 50 offset trim range is 3 3 mV Vs Vs Figure 26 Offset Voltage Nulling Circuit 14 Programmable Gain Amplifier PGA The combination of low noise low input bias current low input offset voltage and low temperature drift make the AD8610 a perfect solution for programmable gain amplifiers PGAs are often used immediately after sensors to increase the dynamic range of the measurement circuit Historically the large ON resistance of switches combined with the large Ig currents of amplifiers created a large dc offset in PGAs Recent and improved monolithic switches and amplifiers completely remove these problems A PGA discrete circuit is shown in Figure 27 In Figure 27 when the 10 pA bias current of the AD8610 is dropped across the 5 Ron of the switch it results in a negligible offset error When high precision resistors are used as in the circuit of Figure 27 the error introduced by the PGA is within the
13. 00 40 25 85 125 TEMPERATURE C 3 95 4 00 4 05 4 10 4 15 4 20 OUTPUT VOLTAGE LOW V 4 25 4 30 40 25 85 125 TEMPERATURE C TPC 12 Output Voltage Low vs Temperature at 5 V Vs 13V RL 1kO MARKER AT 27MHz 69 5 GAIN dB FREQUENCY MHz TPC 15 Open Loop Gain and Phase vs Frequency Ayo V mV 40 25 85 125 TEMPERATURE C TPC 18 Ayo vs Temperature at 5 V REV D PHASE Degrees AD8610 AD8620 160 160 122 140 Vg 5V 120 120 121 100 100 120 g 80 n 80 4PSRR m c 60 60 d 119 K tr 2 40 40 PSRR a 20 20 118 0 0 117 20 20 40 40 116 100 1k 10k 100k 1M 10M 60M 100 1k 10k 100k 1M
14. 1 2 LSB requirement for a 16 bit system 74HC139 Figure 27 High Precision PGA 1 Room temperature error calculation due to Roy and Ig AVos Ig X Ron 2 5 Q 10pV Total Offset ADS8610 Offset AV os Total Offset AD8610 Offset_Trimmed AVos Total Offset 5 UV 10pV 5 2 Full temperature error calculation due to Roy and Ig AVos 85 C Ig 85 C x Roy 85 C 250 pA x15 Q 3 75 nV 3 Temperature coefficient of switch and AD8610 AD8620 combined is essentially the same as the Tc Vos of the AD8610 AVos AT total AVos AT AD8610 AVos AT Ip X Row AVos AT total 0 5 p V C 0 06 nV C 0 5 wV C REV D High Speed Instrumentation Amplifier IN The three op amp instrumentation amplifiers shown in Figure 28 can provide a range of gains from unity up to 1 000 or higher The instrumentation amplifier configuration features high common mode rejection balanced differential inputs and stable accurately defined gain Low input bias currents and fast settling are achieved with the JFET input AD8610 AD8620 Most instrumentation amplifiers cannot match the high frequency performance of this circuit The circuit bandwidth is 25 MHz at a gain of 1 and close to 5 MHz at a gain of 10 Settling time for the entire circuit is 550 ns to 0 01 for a 10 V step gain 10 Note that the resistors around the input pins need to be small enough in value so that the RC time constant they form in combin
15. ANALOG DEVICES Precision Very Low Noise Low Input Bias Current Wide Bandwidth JFET Operational Amplifier AD8610 AD8620 FEATURES Low Noise 6 nV VHz Low Offset Voltage 100 pV Max Low Input Bias Current 10 pA Max Fast Settling 600 ns to 0 01 Low Distortion Unity Gain Stable No Phase Reversal Dual Supply Operation 5 V to 13 V APPLICATIONS Photodiode Amplifier ATE Instrumentation Sensors and Controls High Performance Filters Fast Precision Integrators High Performance Audio GENERAL DESCRIPTION The AD8610 AD8620 is a very high precision JFET input amplifier featuring ultralow offset voltage and drift very low input voltage and current noise very low input bias current and wide bandwidth Unlike many JFET amplifiers the AD8610 AD8620 input bias current is low over the entire operating temperature range The AD8610 AD8620 is stable with capacitive loads of over 1000 pF in noninverting unity gain much larger capacitive loads can be driven easily at higher noise gains The AD8610 AD8620 swings to within 1 2 V of the supplies even with a 1 kQ load maximizing dynamic range even with limited supply voltages Outputs slew at 50 V us in either inverting or noninverting gain configurations and settle to 0 01 accuracy in less than 600 ns Combined with the high input impedance great precision and very high output drive the REV D Information furnished by Analog Devices is believed to be accurate and rel
16. EMPERATURE C Figure 3 Supply Current vs Temperature AD8610 AD8620 Driving Large Capacitive Loads The AD8610 has excellent capacitive load driving capability and can safely drive up to 10 nF when operating with 5 V supply Figures 4 and 5 compare the AD8610 AD8620 against the OPA627 in the noninverting gain configuration driving a 10 kO resistor and 10 000 pF capacitor placed in parallel on its output with a square wave input set to a frequency of 200 kHz The AD8610 has much less ringing than the OPA627 with heavy capacitive loads Vs 5V RL 10kQ CL 10 000 VOLTAGE 20mV DIV TIME 2ys DIV Figure 4 OPA627 Driving C 10 000 pF Vg 5V RL 10kO C 10 000pF VOLTAGE 20mV DIV TIME 2ys DIV Figure 5 AD8610 AD8620 Driving C 10 000 pF The AD8610 AD8620 can drive much larger capacitances without any external compensation Although the AD8610 AD8620 is stable with very large capacitive loads remember that this capacitive loading will limit the bandwidth of the amplifier Heavy capacitive loads will also increase the amount of overshoot and ringing at the output Figures 7 and 8 show the AD8610 AD8620 and the OPA627 in a noninverting gain of 2 driving 2 UF of capacitance load The ringing on the OPA627 is much larger in magnitude and continues more than 10 times longer than the AD8610 10
17. R REEL 40 C to 125 C 8 Lead SOIC RN 8 AD8610BR REEL7 40 C to 125 C 8 Lead SOIC RN 8 AD8610BRZ 40 C to 125 C 8 Lead SOIC RN 8 AD8610BRZ REEL 40 C to 125 C 8 Lead SOIC RN 8 AD8610BRZ REEL7 40 C to 125 C 8 Lead SOIC RN 8 AD8620AR 40 C to 125 C 8 Lead SOIC RN 8 AD8620AR REEL 40 C to 125 C 8 Lead SOIC RN 8 AD8620AR REEL7 40 C to 125 C 8 Lead SOIC RN 8 AD8620BR 40 C to 125 C 8 Lead SOIC RN 8 AD8620BR REEL 40 C to 125 C 8 Lead SOIC RN 8 AD8620BR REEL7 40 C to 125 C 8 Lead SOIC RN 8 Pb free part 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 AD8610 AD8620 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 WARNING ESD SENSITIVE DEVICE REV D Typical Performance Characteristics AD8610 AD8620
18. Signal Voltage Gain Avo Rr 1 kQ Vo 10 V to 10 V 100 200 V mV Offset Voltage Drift AD8610B AVos AT 40 C lt lt 125 C 0 5 1 uVv C Offset Voltage Drift AD8620B AVos AT 40 C lt lt 125 C 0 5 1 5 uVv C Offset Voltage Drift AD8610A AD8620A AVos AT 40 C lt T4 lt 125 0 8 3 5 uVv C OUTPUT CHARACTERISTICS Output Voltage High Vou Ry 1 kQ 40 C lt Ta lt 125 C 11 75 11 84 V Output Voltage Low Vor 1 40 lt lt 125 C 11 84 11 75 V Output Current lour Vour gt 10V 45 Short Circuit Current Isc 65 mA POWER SUPPLY Power Supply Rejection Ratio PSRR Vs 5Vto 13V 100 110 dB Supply Current Amplifier Isy Vo 0V 3 0 3 5 mA 40 C lt Ta lt 125 3 5 4 0 mA DYNAMIC PERFORMANCE Slew Rate SR Ry 2 kQ 40 60 V us Gain Bandwidth Product GBP 25 MHz Settling Time ts Ay 1 10 V Step to 0 01 600 ns NOISE PERFORMANCE Voltage Noise en p p 0 1 Hz to 10 Hz 1 8 Voltage Noise Density en f 1 kHz 6 nV VHz Current Noise Density 1g f 1 kHz 5 fA VHz Input Capacitance Cyn Differential 8 pF Common Mode 15 pF Channel Separation Cs f 10 kHz 137 dB f 300 kHz 120 dB Specifications subject to change without notice REV D AD8610 AD8620 ABSOLUTE MAXIMUM RATINGS Supply Voltage oss sbb La au ee a 27 3 V Package Type em Input Voltage ee eee Vs to Vs 8 MSOP RM 190 44 C W
19. Supply Current vs Supply Voltage Temperature at 13 V Temperature at 5 V REV D 5 AD8610 AD8620 OUTPUT VOLTAGE HIGH V CLOSED LOOP GAIN dB OUTPUT VOLTAGE TO SUPPLY RAIL V 1 8 Vs 13V 1 6 1 4 1 2 1 0 0 8 0 6 0 4 0 2 0 100 1k 10k 100k 1M 10M 100M RESISTANCE LOAD Q TPC 10 Output Voltage to Supply Rail vs Load 12 05 Vs 13V RL 1kQ 12 00 11 95 11 90 11 85 11 80 40 25 85 125 TEMPERATURE C TPC 13 Output Voltage High vs Temperature at 13 V 60 Vg 13V 2kQ CL 20pF 40 20 1k 10k 100k 1M 10M 100M FREQUENCY Hz TPC 16 Closed Loop Gain vs Frequency OUTPUT VOLTAGE LOW V TPC 17 Ayo vs Temperature at 13 V 4 25 Vg 5V RL 1kQ 4 20 4 15 4 10 4 05 OUTPUT VOLTAGE HIGH V 4 00 3 95 40 25 85 125 TEMPERATURE C TPC 11 Output Voltage High vs Temperature at 5 V 11 80 11 85 11 90 11 95 12 00 12 05 40 25 85 125 TEMPERATURE C TPC 14 Output Voltage Low vs Temperature at 13 V 260 240 220 200 180 Ayo V mV 160 140 120 1
20. Supply Rejection Ratio PSRR Vs 5 V to 213 V 100 110 dB Supply Current Amplifier Isy Vo 0V 2 5 3 0 mA 40 C lt T4 lt 125 C 3 0 3 5 mA DYNAMIC PERFORMANCE Slew Rate SR Ry 2 kQ 40 50 V us Gain Bandwidth Product GBP 25 MHz Settling Time ts Ay 1 4 V Step to 0 01 350 ns NOISE PERFORMANCE Voltage Noise en 0 1 Hz to 10 Hz 1 8 Voltage Noise Density en f 1 kHz 6 nV VHz Current Noise Density in f 1 kHz 5 fA VHz Input Capacitance Cm Differential pF Common Mode 15 pF Channel Separation Cs f 10 kHz 137 dB f 300 kHz 120 dB Specifications subject to change without notice 2 REV D ELECTRICAL SPECIFICATIONS V 13 V Vey 0 V T 25 C unless otherwise noted AD8610 AD8620 Parameter Symbol Conditions Min Typ Max Unit INPUT CHARACTERISTICS Offset Voltage AD8610B Vos 45 100 uv 409C lt Ty lt 125 80 200 uv Offset Voltage AD8620B Vos 45 150 uv 40 C lt T4 lt 125 C 80 300 uV Offset Voltage AD8610A AD8620A Vos 85 250 uv 25 lt Ta lt 125 90 350 uv 40 C lt T4 lt 125 C 150 850 uv Input Bias Current Ip 10 3 10 40 lt T4 lt 85 250 130 250 pA 40 lt T4 lt 125 C 3 5 3 5 nA Input Offset Current Ios 10 1 5 10 40 lt Ta lt 85 75 20 75 pA 40 C lt T4 lt 125 C 150 40 150 pA Input Voltage Range 10 5 10 5 V Common Mode Rejection Ratio CMRR Vem 10 V to 10 V 90 110 dB Large
21. The very wide specified temperature range up to 125 C guarantees superior operation in systems with little or no active cooling The unique input architecture of the AD8610 features extremely low input bias currents and very low input offset voltage Low power consumption minimizes the die temperature and maintains the very low input bias current Unlike many competitive JFET amplifiers the AD8610 AD8620 input bias currents are low even at elevated temperatures Typical bias currents are less than 200 pA at 85 The gate current of a JEET doubles every 10 C resulting in a similar increase in input bias current over temperature Special care should be given to the PC board layout to minimize leakage currents between PCB traces Improper layout and board handling generates leakage current that exceeds the bias current of the AD8610 AD8620 REV D FREQUENCY kHz Figure 2 AD8620 Channel Separation Graph Power Consumption A major advantage of the AD8610 AD8620 in new designs is the saving of power Lower power consumption of the AD8610 makes it much more attractive for portable instrumentation and for high density systems simplifying thermal management and reducing power supply performance requirements Compare the power consumption of the AD8610 AD8620 versus the OPA627 in Figure 3 8 7 OPA627 1 6 z w 5 2 o A 4 2 o 3 AD8610 2 75 50 25 0 25 50 75 100 125 T
22. ation with stray circuit capacitance does not reduce circuit bandwidth Vii 1 2 AD8620 X7 c2 10pF Figure 28 High Speed Instrumentation Amplifier High Speed Filters The four most popular configurations are Butterworth Elliptical Bessel and Chebyshev Each type has a response that is optimized for a given characteristic as shown in Table II AD8610 AD8620 In active filter applications using operational amplifiers the dc accuracy of the amplifier is critical to optimal filter performance The amplifier s offset voltage and bias current contribute to output error Input offset voltage is passed by the filter and may be amplified to produce excessive output offset For low frequency applications requiring large value input resistors bias and offset currents flowing through these resistors will also generate an offset voltage At higher frequencies an amplifier s dynamic response must be carefully considered In this case slew rate bandwidth and open loop gain play a major role in amplifier selection The slew rate must be both fast and symmetrical to minimize distortion The amplifier s bandwidth in conjunction with the filter s gain will dictate the frequency response of the filter The use of a high perfor mance amplifier such as the AD8610 AD8620 will minimize both dc and ac errors in all active filter applications Second Order Low Pass Filter Figure 29 shows the AD8610 configured as a second order
23. iable However no responsibility is assumed by Analog Devices for its use norfor any infringements of patents or other rights ofthird parties that may result from its use 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 FUNCTIONAL BLOCK DIAGRAMS 8 Lead MSOP and SOIC RM 8 and R 8 Suffixes NULL 1 8 NC IN C Ci V N C AAD96190 1O0UT v 44 5 H NULL NC NO CONNECT 8 Lead SOIC R 8 Suffix OUTA 1 8 Ee 7 V INAC Ap8620 OUTB INA CA F INB v 4 5 1 INB AD8610 AD8620 is an ideal amplifier for driving high performance A D inputs and buffering D A converter outputs Applications for the AD8610 AD8620 include electronic instru ments ATE amplification buffering and integrator circuits CAT MRI ultrasound medical instrumentation instrumentation quality photodiode amplification fast precision filters including PLL filters and high quality audio The AD8610 AD8620 is fully specified over the extended industrial 40 C to 125 temperature range The AD8610 is available in the narrow 8 lead SOIC and the tiny MSOP8 surface mount packages The AD8620 is available in the narrow 8 lead SOIC package MSOPS packaged devices are available only in tape and reel 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
24. ifier generally makes its SR appear worse The slew rate of an amplifier varies according to the voltage difference between its two inputs To observe the maximum SR as specified 5 SR 42 1V us in the AD8610 data sheet a difference voltage of about 2 V between the inputs must be ensured This will be required for virtually JFET op amp so that one side of the op amp input circuit is g pletely off maximizing the current available to charge and discharge the internal compensation capacitance Lower differential drive voltages will produce lower slew rate readings A JFET input op amp with a slew rate of 60 V us at unity gain with Vin 10 V might slew at 20 V us if it is operated at a gain of TIME 400ns DIV 100 with V 100 mV Figure 10 SR of OPA627 in Unity Gain of 1 The slew rate of the AD8610 AD8620 is double that of the OPA627 when configured in a unity gain of 1 see Figures 13 and 14 Vs 13V RL 2kQ G 1 At tt a SR 54V us 1 gt ji i e g TIME 400ns DIV TIME 400ns DIV Figure 13 SR of AD8610 AD8620 in Unity Gain of 1 Figure 11 SR of AD8610 AD8620 in Unity Gain of 1 REV D 11 AD8610 AD8620 i Tt VOLTAGE 5V DIV Figure 14 SR of OPA627 in Unity Gain of 1 The slew rate of an amplifier determines the maximum frequency at which it can respond to a large signal input This frequency known a
25. n op amps Unfortunately clamp 2 diodes greatly interfere with many application circuits such as precision rectifiers and comparators The AD8610 is free from these limitations 13V 7 4 AD8610 13V Figure 16 Unity Gain Follower No Phase Reversal Many amplifiers misbehave when one or both of the inputs are forced beyond the input common mode voltage range Phase reversal is typified by the transfer function of the amplifier effectively reversing its transfer polarity In some cases this can cause lockup and even equipment damage in servo systems and may cause permanent damage or nonrecoverable parameter shifts to the amplifier itself Many amplifiers feature compensation circuitry to combat these effects but some are only effective for the inverting input The AD8610 AD8620 is designed to prevent phase reversal when one or both inputs are forced beyond their input common mode voltage range ViN VOLTAGE 5V DIV TIME 400ps DIV Figure 17 No Phase Reversal THD Readings vs Common Mode Voltage Total harmonic distortion of the AD8610 AD8620 is well below 0 0006 with any load down to 600 Q The AD8610 AD8620 outperforms the OPA627 for distortion especially at frequen cies above 20 kHz 0 1 Vsy 13V Vin 5V rms BW 80kHz 0 01 xX z Q I F 0 001 0 0001 10 100 1k 10k 80k FREQUENCY
26. p p 20V Ay 2 1 RL 2kQ SR 55V p s C 20pF TIME 400ns DIV TIME 400ns DIV TPC 37 SR at G 1 TPC 38 SR at G 1 CS dB 20 log 10 x Vin 138 136 134 132 Q9 Figure 1 Channel Separation Test Circuit T 158 o FUNCTIONAL DESCRIPTION 128 AD8610 AD8620 is manufactured on Analog Devices Inc s 124 proprietary XFCB eXtra Fast Complementary Bipolar process XFCB is fully dielectrically isolated DI and used in conjunc 122 tion with N channel JFET technology and trimmable thin film 120 0 50 100 150 200 250 300 350 resistors to create the world s most precise JFET input amplifier Dielectrically isolated NPN and PNP transistors fabricated on XFCB have greater than 3 GHz Low T thin film resistors enable very accurate offset voltage and offset voltage tempco trimming These process breakthroughs allowed Analog Devices world class IC designers to create an amplifier with faster slew rate and more than 50 higher bandwidth at half of the current consumed by its closest competition The AD8610 is uncondi tionally stable in all gains even with capacitive loads well in excess of 1 nF The AD8610B achieves less than 100 uV of offset and 1 uV C of offset drift numbers usually associated with very high precision bipolar input amplifiers The AD8610 is offered in the tiny 8 lead MSOP as well as narrow 8 lead SOIC surface mount packages and is fully specified with supply voltages from 5 V to 13 V
27. ry Location Page 2 04 Data Sheet changed from REV C to REV D Changes t6 SPECIFICATIONS V despecta Renta eg in eerte a Munck d r dehy dow ege e Rep UU TU RR Pe Re 2 Changes to ORDERING GUIDE 424454 Vis vla B Gn UR Ma Rude S pue bp es dex teuer om A den et a P a eR eus 4 Updated OUTLINE DIMENSIONS e ere eoe ey rep ace Bled dod e pred ees T io s 17 10 02 Data Sheet changed from REV B to REV C Updated ORDERING GUIDE el Gan REPRE RUE eta CHEST REA PEERS pes b Keep x EE 4 EQNS LEE 12 Updated OUTLINE DIMENSIONS 5 Ra kan RE SI BO RR A RUE RR R RT R A R R XO e RR 16 5 02 Data Sheet changed from REV A to REV B Addition of part number AD8620 eodcm oe qox e en RA CR R I M teh Sca dre do d e ree Universal Addition of 8 Lead SOIC R 8 Suffix Drawing 0 eee rr hn rh 1 Changesto GENERAL DESCRIPTION RU RR T doe P ee e e RR PH RR e ada RC d te ele 1 Additions to SPECIFICATIONS ans was d see p eC E EROR dre Re RR ee ROW EARS EN qup 2 Change to ELECTRICAL SPECIFICATIONS 24 542 esos ere oed eer EE C RIVIERA eR dae PG e Re EEA ce ee 3 Additions to ORDERING GUIDE Cer oor e Reg a e Sud ec at a Re bc oe e r DR i dea pine qs 4 Replace 29 iii ee eese S Pb E deus ade Buda aoo ba Und One On dto Spd od ded 8 Add Channel Separation Test Circuit Figure
28. s full power bandwidth or FPBW can be calculated from the equation TIME 400ns DIV SR 2x x Vpgak for a given distortion e g 1 FPBW CH 20 8V p ov 2 a 2 e 1 9 19 4V pp a g ov TIME 400ns DIV Figure 15 AD8610 FPBW Input Overvoltage Protection When the input of an amplifier is driven below Vgg or above Vcc by more than one Vb large currents will flow from the substrate through the negative supply V or the positive supply V respectively to the input pins which can destroy the device If the input source can deliver larger currents than the maximum forward current of the diode 75 mA a series resistor can be added to protect the inputs With its very low input bias and offset current a large series resistor can be placed in front of the AD8610 inputs to limit current to below damaging levels Series resistance of 10 kO will generate less than 25 uV of offset This 10 will allow input voltages more than 5 V beyond either power supply Thermal noise generated by the resistor will add 7 5 nV VHz to the noise of the AD8610 For the AD8610 AD8620 differential voltages equal to the supply voltage will not cause any problem see Figure 15 In this context it should also be noted that the high breakdown voltage of the input FETs eliminates the need to include clamp diodes between the inputs of the amplifier a practice that is mandatory on many precisio

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