AD820AN-3V

AD820 AD | Alldatasheet

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8-Lead Plastic Mini-DIP 8-Lead SOIC REV. B 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. a Single Supply, Rail to Rail Low Power FET-Input Op Amp AD820 Tel: 781/329-4700 World Wide Web Site: http://www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 1999

FEATURES

True Single Supply Operation Output Swings Rail-to-Rail Input Voltage Range Extends Below Ground Single Supply Capability from +3 V to +36 V Dual Supply Capability from 61.5 V to 618 V Excellent Load Drive Capacitive Load Drive Up to 350 pF Minimum Output Current of 15 mA Excellent AC Performance for Low Power 800 mA Max Quiescent Current Unity Gain Bandwidth: 1.8 MHz Slew Rate of 3.0 V/ ms Excellent DC Performance 800 mV Max Input Offset Voltage 1 mV/8C Typ Offset Voltage Drift 25 pA Max Input Bias Current Low Noise 13 nV/ ÖHz @ 10 kHz

APPLICATIONS

Battery Powered Precision Instrumentation Photodiode Preamps Active Filters 12- to 14-Bit Data Acquisition Systems Medical Instrumentation Low Power References and Regulators PRODUCT DESCRIPTION The AD820 is a precision, low power FET input op amp that can operate from a single supply of +3.0 V to 36 V, or dual supplies of – 1.5 V to – 18 V. It has true single supply capability with an input voltage range extending below the negative rail, 98765432 INPUT BIAS CURRENT – pA NUMBER OF UNITS Figure 1. Typical Distribution of Input Bias Current provide dc precision with source impedances up to a Gigaohm.

1.8 MHz unity gain bandwidth, –93 dB THD at 10 kHz and

3 V/ms slew rate are provided for a low supply current of

allows the amplifier to handle a wide range of load conditions. amplifier for the single supply user. over the industrial temperature range. DIP, and surface mount (SOIC). Figure 2. Gain of +2 Amplifier; V S = +5, 0, VIN = 2.5 V Sine

REV. B–2– AD820–SPECIFICATIONS(VS = 0, 5 volts @ TA = +258C, VCM = 0 V, VOUT = 0.2 V unless otherwise noted) AD820A AD820B Parameter Conditions Min Typ Max Min Typ Max Units DC PERFORMANCE Initial Offset 0.1 0.8 0.1 0.4 mV Max Offset over Temperature 0.5 1.2 0.5 0.9 mV Offset Drift 2 2 mV/°C Input Bias Current V O = 0 V to 4 V 2 25 2 10 pA at TMAX 0.5 5 0.5 2.5 nA Input Offset Current 2 20 2 10 pA at TMAX 0.5 0.5 nA Open-Loop Gain V O = 0.2 V to 4 V RL = 100k 400 1000 500 1000 V/mV TMIN to TMAX 400 400 V/mV RL = 10k 80 150 80 150 V/mV TMIN to TMAX 80 80 V/mV RL = 1k 15 30 15 30 V/mV TMIN to TMAX 10 10 V/mV NOISE/HARMONIC PERFORMANCE Input Voltage Noise

0.1 Hz to 10 Hz 2 2 mV p-p

f = 10 Hz 25 25 nV/ ÖHz f = 100 Hz 21 21 nV/ ÖHz f = 1 kHz 16 16 nV/ ÖHz f = 10 kHz 13 13 nV/ ÖHz Input Current Noise

0.1 Hz to 10 Hz 18 18 fA p-p

f = 1 kHz 0.8 0.8 fA/ ÖHz Harmonic Distortion R L = 10k to 2.5 V f = 10 kHz V O = 0.25 V to 4.75 V –93 –93 dB DYNAMIC PERFORMANCE Unity Gain Frequency 1.8 1.8 MHz Full Power Response V O p-p = 4.5 V 210 210 kHz Slew Rate 3 3 V/ ms Settling Time to 0.01% 1.8 1.8 ms INPUT CHARACTERISTICS Common-Mode Voltage Range 1 –0.2 4 –0.2 4 V TMIN to TMAX –0.2 4 –0.2 4 V CMRR V CM = 0 V to +2 V 66 80 72 80 dB TMIN to TMAX 66 66 dB Input Impedance Differential 10 13i0.5 10 13i0.5 W ipF Common Mode 10 13i2.8 10 13i2.8 W ipF OUTPUT CHARACTERISTICS Output Saturation Voltage 2 VOL–VEE ISINK = 20 mA 5 7 57m V TMIN to TMAX 10 10 mV VCC–VOH ISOURCE = 20 mA 1 0 1 4 1 01 4m V TMIN to TMAX 20 20 mV VOL–VEE ISINK = 2 mA 40 55 40 55 mV TMIN to TMAX 80 80 mV VCC–VOH ISOURCE = 2 mA 80 110 80 110 mV TMIN to TMAX 160 160 mV VOL–VEE ISINK = 15 mA 300 500 300 500 mV TMIN to TMAX 1000 1000 mV VCC–VOH ISOURCE = 15 mA 800 1500 800 1500 mV TMIN to TMAX 1900 1900 mV Operating Output Current 15 15 mA TMIN to TMAX 12 12 mA Short Circuit Current 25 25 mA Capacitive Load Drive 350 350 pF POWER SUPPLY Quiescent Current T MIN to TMAX 620 800 620 800 mA Power Supply Rejection V S+ = 5 V to 15 V 70 80 66 80 dB TMIN to TMAX 70 66 dB

–3–REV. B (VS = +5 volts @ TA = +258C, VCM = 0 V, VOUT = 0 V unless otherwise noted) AD820A AD820B Parameter Conditions Min Typ Max Min Typ Max Units DC PERFORMANCE Initial Offset 0.1 0.8 0.3 0.4 mV Max Offset over Temperature 0.5 1.5 0.5 1 mV Offset Drift 2 2 mV/°C Input Bias Current V CM = –5 V to 4 V 2 25 2 10 pA at TMAX 0.5 5 0.5 2.5 nA Input Offset Current 2 20 2 10 pA at TMAX 0.5 0.5 nA Open-Loop Gain V O = 4 V to –4 V RL = 100k 400 1000 400 1000 V/mV TMIN to TMAX 400 400 V/mV RL = 10k 80 150 80 150 V/mV TMIN to TMAX 80 80 V/mV RL = 1k 20 30 20 30 V/mV TMIN to TMAX 10 10 V/mV NOISE/HARMONIC PERFORMANCE Input Voltage Noise f = 10 Hz 25 25 nV/ ÖHz f = 100 Hz 21 21 nV/ ÖHz f = 1 kHz 16 16 nV/ ÖHz f = 10 kHz 13 13 nV/ ÖHz Input Current Noise f = 1 kHz 0.8 0.8 fA/ ÖHz Harmonic Distortion R L = 10k f = 10 kHz V O = – 4.5 V –93 –93 dB DYNAMIC PERFORMANCE Unity Gain Frequency 1.9 1.8 MHz Full Power Response V O p-p = 9 V 105 105 kHz Slew Rate 3 3 V/ ms Settling Time to 0.1% V O = 0 V to – 4.5 V 1.4 1.4 ms to 0.01% 1.8 1.8 ms INPUT CHARACTERISTICS Common-Mode Voltage Range 1 –5.2 4 –5.2 4 V TMIN to TMAX –5.2 4 –5.2 4 V CMRR V CM = –5 V to +2 V 66 80 72 80 dB TMIN to TMAX 66 66 dB Input Impedance Differential 10 13i0.5 10 13i0.5 W ipF Common Mode 10 13i2.8 10 13i2.8 W ipF OUTPUT CHARACTERISTICS Output Saturation Voltage 2 VOL–VEE ISINK = 20 mA 5 7 57m V TMIN to TMAX 10 10 mV VCC–VOH ISOURCE = 20 mA 1 0 1 4 1 01 4m V TMIN to TMAX 20 20 mV VOL–VEE ISINK = 2 mA 40 55 40 55 mV TMIN to TMAX 80 80 mV VCC–VOH ISOURCE = 2 mA 80 110 80 110 mV TMIN to TMAX 160 160 mV VOL–VEE ISINK = 15 mA 300 500 300 500 mV TMIN to TMAX 1000 1000 mV VCC–VOH ISOURCE = 15 mA 800 1500 800 1500 mV TMIN to TMAX 1900 1900 mV Operating Output Current 15 15 mA TMIN to TMAX 12 12 mA Short Circuit Current 30 30 mA Capacitive Load Drive 350 350 pF POWER SUPPLY Quiescent Current T MIN to TMAX 650 800 620 800 mA Power Supply Rejection V S+ = 5 V to 15 V 70 80 70 80 dB TMIN to TMAX 70 70 dB

Parameter Conditions Min Typ Max Min Typ Max Units DC PERFORMANCE Initial Offset 0.4 2 0.3 1.0 mV Max Offset over Temperature 0.5 3 0.5 2 mV Offset Drift 2 2 mV/°C Input Bias Current V CM = 0 V 2 25 2 10 pA VCM = –10 V 40 40 pA at TMAX VCM = 0 V 0.5 5 0.5 2.5 nA Input Offset Current 2 20 2 10 pA at TMAX 0.5 0.5 nA Open-Loop Gain V O = +10 V to –10 V RL = 100k 500 2000 500 2000 V/mV TMIN to TMAX 500 500 V/mV RL = 10k 100 500 100 500 V/mV TMIN to TMAX 100 100 V/mV RL = 1k 30 45 30 45 V/mV TMIN to TMAX 20 20 V/mV NOISE/HARMONIC PERFORMANCE Input Voltage Noise f = 10 Hz 25 25 nV/ ÖHz f = 100 Hz 21 21 nV/ ÖHz f = 1 kHz 16 16 nV/ ÖHz f = 10 kHz 13 13 nV/ ÖHz Input Current Noise f = 1 kHz 0.8 0.8 fA/ ÖHz Harmonic Distortion R L = 10k f = 10 kHz V O = – 10 V –85 –85 dB DYNAMIC PERFORMANCE Unity Gain Frequency 1.9 1.9 MHz Full Power Response V O p-p = 20 V 45 45 kHz Slew Rate 3 3 V/ ms Settling Time to 0.1% V O = 0 V to – 10 V 4.1 4.1 ms to 0.01% 4.5 4.5 ms INPUT CHARACTERISTICS Common-Mode Voltage Range 1 –15.2 14 –15.2 14 V TMIN to TMAX –15.2 14 –15.2 14 V CMRR V CM = –15 V to 12 V 70 80 74 90 dB TMIN to TMAX 70 74 dB Input Impedance Differential 10 13i0.5 10 13i0.5 W ipF Common Mode 10 13i2.8 10 13i2.8 W ipF OUTPUT CHARACTERISTICS Output Saturation Voltage 2 VOL–VEE ISINK = 20 mA 5 7 57m V TMIN to TMAX 10 10 mV VCC–VOH ISOURCE = 20 mA 1 0 1 4 1 01 4m V TMIN to TMAX 20 20 mV VOL–VEE ISINK = 2 mA 40 55 40 55 mV TMIN to TMAX 80 80 mV VCC–VOH ISOURCE = 2 mA 80 110 80 110 mV TMIN to TMAX 160 160 mV VOL–VEE ISINK = 15 mA 300 500 300 500 mV TMIN to TMAX 1000 1000 mV VCC–VOH ISOURCE = 15 mA 800 1500 800 1500 mV TMIN to TMAX 1900 1900 mV Operating Output Current 20 20 mA TMIN to TMAX 15 15 mA Short Circuit Current 45 45 mA Capacitive Load Drive 350 350 POWER SUPPLY Quiescent Current T MIN to TMAX 700 900 700 900 mA Power Supply Rejection V S+ = 5 V to 15 V 70 80 70 80 dB TMIN to TMAX 70 70 dB AD820–SPECIFICATIONS –4– REV. B (VS = 615 volts @ TA = +258C, VCM = 0 V, VOUT = 0 V unless otherwise noted)

(VS = 0, 3 volts @ TA = +258C, VCM = 0 V, VOUT = 0.2 V unless otherwise noted) AD820A-3V Parameter Conditions Min Typ Max Units DC PERFORMANCE Initial Offset 0.2 1 mV Max Offset over Temperature 0.5 1.5 mV Offset Drift 1 mV/°C Input Bias Current V CM = 0 V to +2 V 2 25 pA at TMAX 0.5 5 nA Input Offset Current 22 0 p A at TMAX 0.5 nA Open-Loop Gain V O = 0.2 V to 2 V RL = 100k 300 1000 V/mV TMIN to TMAX 400 V/mV RL = 10k 60 150 V/mV TMIN to TMAX 80 V/mV RL = 1k 10 30 V/mV TMIN to TMAX 8 V/mV NOISE/HARMONIC PERFORMANCE Input Voltage Noise

0.1 Hz to 10 Hz 2 mV p-p

f = 10 Hz 25 nV/ ÖHz f = 100 Hz 21 nV/ ÖHz f = 1 kHz 16 nV/ ÖHz f = 10 kHz 13 nV/ ÖHz Input Current Noise

0.1 Hz to 10 Hz 18 fA p-p

f = 1 kHz 0.8 fA/ ÖHz Harmonic Distortion R L = 10k to 1.5 V f = 10 kHz V O = – 1.25 V –92 dB DYNAMIC PERFORMANCE Unity Gain Frequency 1.5 MHz Full Power Response V O p-p = 2.5 V 240 kHz Slew Rate 3V / ms Settling Time to 0.1% V O = 0.2 V to 2.5 V 1 ms to 0.01% 1.4 ms INPUT CHARACTERISTICS Common-Mode Voltage Range 1 –0.2 2 V TMIN to TMAX –0.2 2 V CMRR V CM = 0 V to +1 V 60 74 dB TMIN to TMAX 60 dB Input Impedance Differential 1013i0.5 W ipF Common Mode 1013i2.8 W ipF OUTPUT CHARACTERISTICS Output Saturation Voltage 2 VOL–VEE ISINK = 20 mA5 7 m V TMIN to TMAX 10 mV VCC–VOH ISOURCE = 20 mA1 0 1 4 m V TMIN to TMAX 20 mV VOL–VEE ISINK = 2 mA 40 55 mV TMIN to TMAX 80 mV VCC–VOH ISOURCE = 2 mA 80 110 mV TMIN to TMAX 160 mV VOL–VEE ISINK = 10 mA 200 400 mV TMIN to TMAX 400 mV VCC–VOH ISOURCE = 10 mA 500 1000 mV TMIN to TMAX 1000 mV Operating Output Current 15 mA TMIN to TMAX 12 mA Short Circuit Current 18 25 mA TMIN to TMAX 15 mA Capacitive Load Drive 350 pF POWER SUPPLY Quiescent Current T MIN to TMAX 620 800 mA Power Supply Rejection V S+ = 3 V to 15 V 70 80 dB TMIN to TMAX 70 dB AD820 REV. B –5–

REV. B–6– AD820–SPECIFICATIONS NOTES 1This is a functional specification. Amplifier bandwidth decreases when the input common-mode voltage is driven in the range (+ V S – 1 V) to +VS. Common-mode error voltage is typically less than 5 mV with the common-mode voltage set at 1 volt below the positive supply. 2VOL–VEE is defined as the difference between the lowest possible output voltage (V OL) and the minus voltage supply rail (V EE). VCC–VOH is defined as the difference between the highest possible output voltage (V OH) and the positive supply voltage (V CC). Specifications subject to change without notice. ABSOLUTE MAXIMUM RATINGS 1 Internal Power Dissipation 2 S + 0.2 V) to – (20 V + VS) Operating Temperature Range Lead Temperature Range NOTES 1Stresses above those listed under Absolute Maximum Ratings may cause perma- nent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. 28-Lead Plastic DIP Package: qJA = 90°C/Watt 8-Lead SOIC Package: qJA = 160°C/Watt ORDERING GUIDE Temperature Package Package Model Range Description Options AD820AN –40 °C to +85°C 8-Lead Plastic Mini-DIP N-8 AD820BN –40 °C to +85°C 8-Lead Plastic Mini-DIP N-8 AD820AR –40 °C to +85°C 8-Lead SOIC R-8 AD820BR –40 °C to +85°C 8-Lead SOIC R-8 AD820AR-3V –40 °C to +85°C 8-Lead SOIC R-8 AD820AN-3V –40 °C to +85°C 8-Lead Plastic Mini-DIP N-8 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 AD820 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. B–14– Direct capacitive load will interact with the amplifier’s effective output impedance to form an additional pole in the amplifier’s feedback loop, which can cause excessive peaking on the pulse response or loss of stability. Worst case is when the amplifier is used as a unity gain follower. Figure 40 shows the AD820’s pulse response as a unity gain follower driving 350 pF. This amount of overshoot indicates approximately 20 degrees of phase margin—the system is stable, but is nearing the edge. Configurations with less loop gain, and as a result less loop bandwidth, will be much less sensitive to capacitance load ef- fects. Figure 41 is a plot of capacitive load that will result in a 20 degree phase margin versus noise gain for the AD820. Noise gain is the inverse of the feedback attenuation factor provided by the feedback network in use. Figure 40. Small Signal Response of AD820 as Unity Gain Figure 41. Capacitive Load Tolerance vs. Noise Gain Figure 42. Extending Unity Gain Follower Capacitive Load mended technique for AD820’s packaged in plastic DIPs. Figure 43. Offset Null Single Supply Half-Wave and Full-Wave Rectifiers An AD820 configured as a unity gain follower and operated with a single supply can be used as a simple half-wave rectifier. The AD820’s inputs maintain picoamp level input currents even when driven well below the minus supply. The rectifier puts that behavior to good use, maintaining an input impedance of over

11 W for input voltages from 1 volt from the positive supply to

20 volts below the negative supply. The full and half-wave rectifier shown in Figure 44 operates as follows: when VIN is above ground, R1 is bootstrapped through the unity gain follower A1 and the loop of amplifier A2. This forces the inputs of A2 to be equal, thus no current flows through R1 or R2, and the circuit output tracks the input. When V IN is below ground, the output of A1 is forced to ground. The non- inverting input of amplifier A2 sees the ground level output of A1, therefore A2 operates as a unity gain inverter. The output at node C is then a full-wave rectified version of the input. Node B is a buffered half-wave rectified version of the input. Input volt- ages up to – 18 volts can be rectified, depending on the voltage supply used.

Figure 44. Single Supply Half- and Full-Wave Rectifier

4.5 Volt Low Dropout, Low Power Reference

pass RC filter to reduce the noise contribution of the AD680. Figure 45. Single Supply 4.5 Volt Low Dropout Reference current is under 20 mV, and settles out in a few microseconds. put voltage noise of the filter. Figure 46. 10 Hz Sallen Key Low-Pass Filter

REV. B–16– OUTLINE DIMENSIONS Dimensions shown in inches and (mm). Mini-DIP Package (N-8) SEATING PLANE 0.125 (3.18) MIN 0.035 6 0.01 (0.89 6 0.25) 0.033 (0.84) NOM 0.018 6 0.003 (0.46 6 0.08) 0.165 6 0.01 (4.19 6 0.25) 0.18 6 0.03 (4.57 6 0.75) PIN 1 0.10 (2.54) BSC 0.39 (9.91) MAX 0.25 (6.35) 0.31 (7.87) 0.011 6 0.003 (0.28 6 0.08) 158 0.30 (7.62) REF (R-8) 108 08 0.030 (0.76) 0.018 (0.46) 0.020 (0.051) 3 458 CHAMF 0.098 (0.2482) 0.075 (0.1905) 0.190 (4.82) 0.170 (4.32) 0.090 (2.29) 0.244 (6.20) 0.228 (5.79) PIN 1 0.157 (3.99) 0.150 (3.81) 0.150 (3.81) 0.102 (2.59) 0.094 (2.39) SEATING PLANE 0.010 (0.25) 0.004 (0.10) 0.019 (0.48) 0.014 (0.36) 0.197 (5.01) 0.189 (4.80) 0.050 (1.27) BSC C1792b–0–8/99PRINTED IN U.S.A.