AD215

AD215 120 kHz Bandwidth, Low Distortion, Isolation Amplifier

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REV. 0 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 120 kHz Bandwidth, Low Distortion, Isolation Amplifier AD215 © Analog Devices, Inc., 1996 Tel: 617/329-4700 Fax: 617/326-8703 FUNCTIONAL BLOCK DIAGRAMFEATURES Isolation Voltage Rating: 1,500 V rms Wide Bandwidth: 120 kHz, Full Power (–3 dB) Rapid Slew Rate: 6 V/ ms Fast Settling Time: 9 ms Low Harmonic Distortion: –80 dB @ 1 kHz Low Nonlinearity: 60.005% Wide Output Range: 610 V, min (Buffered) Built-in Isolated Power Supply: 615 V dc @ 610 mA Performance Rated over –40 8C to +85 8C APPLICATIONS INCLUDE High Speed Data Acquisition Systems Power Line and Transient Monitors Multichannel Muxed Input Isolation Waveform Recording Instrumentation Power Supply Controls Vibration Analysis Flexible Input and Buffered Output Stages: An uncommit- ted op amp is provided on the input stage of the AD215 to allow for input buffering or amplification and signal condition- ing. The AD215 also features a buffered output stage to drive low impedance loads and an output voltage trim for zeroing the output offset where needed. High Accuracy: The AD215 has a typical nonlinearity of ± 0.005% (B grade) of full-scale range and the total harmonic distortion is typically –80 dB at 1 kHz. The AD215 provides designers with complete isolation of the desired signal without loss of signal integrity or quality. Excellent Common-Mode Performance: The AD215BY (AD215AY) provides 1,500 V rms (750 V rms) common-mode voltage protection from its input to output. Both grades feature a low common-mode capacitance of 4.5 pF inclusive of the dc/dc power isolation. This results in a typical common-mode rejection specification of 105 dB and a low leakage current of 2.0 µA rms max (240 V rms, 60 Hz). Isolated Power: An unregulated isolated power supply of ± 15 V dc @ ± 10 mA is available at the isolated input port of the AD215. This permits the use of ancillary isolated front-end amplifiers or signal conditioning components without the need for a separate dc/dc supply. Even the excitation of transducers can be accomplished in most applications. Rated Performance over the –408C to +858C Temperature Range: With an extended industrial temperature range rating, the AD215 is an ideal isolation solution for use in many indus- trial environments. GENERAL DESCRIPTION The AD215 is a high speed input isolation amplifier designed to isolate and amplify wide bandwidth analog signals. The innova- tive circuit and transformer design of the AD215 ensures wide- band dynamic characteristics while preserving key dc performance specifications. The AD215 provides complete galvanic isolation between the input and output of the device including the user-available front-end isolated power supplies. The functionally complete design, powered by a ± 15 V dc supply, eliminates the need for a user supplied isolated dc/dc converter. This permits the designer to minimize circuit overhead and reduce overall system design complexity and component costs. The design of the AD215 emphasizes maximum flexibility and ease of use in a broad range of applications where fast analog signals must be measured under high common-mode voltage (CMV) conditions. The AD215 has a ± 10 V input/output range, a specified gain range of 1 V/V to 10 V/V, a buffered out- put with offset trim and a user-available isolated front-end power supply which produces ± 15 V dc at ± 10 mA. PRODUCT HIGHLIGHTS High Speed Dynamic Characteristics: The AD215 features a typical full-power bandwidth of 120 kHz (100 kHz min), rise time of 3 µs and settling time of 9 µs. The high speed perfor- mance of the AD215 allows for unsurpassed galvanic isolation of virtually any wideband dynamic signal. OUT HI TRIM OUT LO +15VIN –15VIN PWR RTN FB IN– IN+ IN COM +V ISO –VISO MODULATOR UNCOMMITTED INPUT OP AMP RR OUTPUT BUFFER 33kΩ 0.01µF DEMODULATOR LOW-PASS FILTER 150kHz POWER ISOLATED DC SUPPLY 430kHz POWER OSCILLATOR AD215 SIGNAL

REV. 0–2– AD215–SPECIFICATIONS(Typical @ +258C, VS = 615 V dc, 2 kV output load, unless otherwise noted.) AD215AY/BY Parameter Conditions Min Typ Max Units GAIN Range1 1 10 V/V Error G = 1 V/V, No Load on V ISO ± 0.5 ± 2% vs. Temperature 0 °C to +85°C +15 ppm/ °C –40°C to 0°C +50 ppm/ °C vs. Supply Voltage ± (14.5 V dc to 16.5 V dc) +100 ppm/V vs. Isolated Supply Load 2 +20 ppm/mA Nonlinearity3 AD215BY Grade ± 10 V Output Swing, G = 1 V/V ± 0.005 ± 0.015 % ± 10 V Output Swing, G = 10 V/V ± 0.01 % AD215AY Grade ± 10 V Output Swing, G = 1 V/V ± 0.01 ± 0.025 % ± 10 V Output Swing, G = 10 V/V ± 0.025 % INPUT VOLTAGE RATINGS Input Voltage Rating G = 1 V/V ± 10 V Maximum Safe Differential Range IN+ or IN–, to IN COM ± 15 V CMRR of Input Op Amp 100 dB Isolation Voltage Rating 4 Input to Output, AC, 60 Hz AD215BY Grade 100% Tested 4 1500 V rms AD215AY Grade 100% Tested 4 750 V rms IMRR (Isolation Mode Rejection Ratio) R S ≤ 100 Ω (IN+ & IN–), G = 1 V/V, 60 Hz 120 dB RS ≤ 100 Ω (IN+ & IN–), G = 1 V/V, 1 kHz 100 dB RS ≤ 100 Ω (IN+ & IN–), G = 1 V/V, 10 kHz 80 dB RS ≤ 1 kΩ (IN+ & IN–), G = 1 V/V, 60 Hz 105 dB RS ≤ 1 kΩ (IN+ & IN–), G = 1 V/V, 1 kHz 85 dB RS ≤ 1 kΩ (IN+ & IN–), G = 1 V/V, 10 kHz 65 dB Leakage Current, Input to Output 240 V rms, 60 Hz 2 µA rms INPUT IMPEDANCE Differential G = 1 V/V 16 M Ω Common Mode 2i4.5 G Ω ipF INPUT OFFSET VOLTAGE Initial @ +25 °C ± 0.4 ± 2.0 mV vs. Temperature 0 °C to +85°C ± 2 µV/°C –40°C to 0°C ± 20 µV/°C OUTPUT OFFSET VOLTAGE Initial @ +25 °C, Trimmable to Zero 0 –35 –80 mV vs. Temperature 0 °C to +85°C ± 30 µV/°C –40°C to 0°C ± 80 µV/°C vs. Supply Voltage ± 350 µV/V vs. Isolated Supply Load 2 –35 µV/mA INPUT BIAS CURRENT Initial @ +25 °C 300 nA vs. Temperature –40 °C to +85°C ± 400 nA INPUT DIFFERENCE CURRENT Initial @ +25 °C ± 3n A vs. Temperature –40 °C to +85°C ± 40 nA INPUT VOLTAGE NOISE Input Voltage Noise Frequency > 10 Hz 20 nV/ √Hz DYNAMIC RESPONSE (2 kΩ Load) Full Signal Bandwidth (–3 dB) G = 1 V/V, 20 V pk-pk Signal 100 120 kHz Transport Delay6 2.2 µs Slew Rate ± 10 V Output Swing 6 V/ µs Rise Time 10% to 90%, ± 10 V Output Swing 3 µs

REV. 0 –3– AD215AY/BY Parameter Conditions Min Typ Max Units DYNAMIC RESPONSE (2 kΩ Load) Cont. Settling Time to ± 0.10%, ± 10 V Output Swing 9 µs Overshoot 1% Harmonic Distortion Components @ 1 kHz –80 dB @ 10 kHz –65 dB Overload Recovery Time G = 1 V/V, ± 15 V Drive 5 µs Output Overload Recovery Time G > 5 10 µs RATED OUTPUT Voltage Out HI to Out LO ± 10 V Current 2 k Ω Load ± 5m A Max Capacitive Load 500 pF Output Resistance 1 Ω Output Ripple and Noise 7 1 MHz Bandwidth 10 mV pk-pk 50 kHz Bandwidth 2.5 mV pk-pk ISOLATED POWER OUTPUT8 Voltage No Load ± 14.25 ± 15 ± 17.25 V vs. Temperature 0 °C to +85°C +20 mV/ °C –40°C to 0°C +25 mV/ °C Current at Rated Supply Voltage 2, 9 ± 10 mA Regulation No Load to Full Load –90 mV/V Line Regulation 290 mV/V Ripple 1 MHz Bandwidth, No Load 2 50 mV rms POWER SUPPLY Supply Voltage Rated Performance ± 14.5 ± 15 ± 16.5 V dc Operating10 ± 14.25 ± 17 V dc Current Operating (+15 V dc/–15 V dc Supplies) +40/–18 mA TEMPERATURE RANGE Rated Performance –40 +85 °C Storage –40 +85 °C NOTES 11The gain range of the AD215 is specified from 1 to 10 V/V. The AD215 can also be used with gains of up to 100 V/V. With a gain of 100 V/V a 20% reduction in the –3 dB bandwidth specification occurs and the nonlinearity degrades to ± 0.02% typical. 12When the isolated supply load exceeds ± 1 mA, external filter capacitors are required in order to ensure that the gain, offset, and nonlinearity specifications are pre- served and to maintain the isolated supply full load ripple below the specified 50 mV rms. A value of 6.8 µF is recommended. 13Nonlinearity is specified as a percent (of full-scale range) deviation from a best straight line. 14The isolation barrier (and rating) of every AD215 is 100% tested in production using a 5 second partial discharge test with a failure detection threshold of 150 pC. All “B” grade devices are tested with a minimum voltage of 1,800 V rms. All “A” grade devices are tested with a minimum voltage of 850 V rms. 15The AD215 should be allowed to warm up for approximately 10 minutes before any gain and/or offset adjustments are made. 16Equivalent to a 0.8 degrees phase shift. 17With the ± 15 V dc power supply pins bypassed by 2.2 µF capacitors at the AD215 pins. 18Caution: The AD215 design does not provide short circuit protection of its isolated power supply. A current limiting resistor may be placed in series with the isolated power terminals and the load in order to protect the supply against inadvertent shorts. 19With an input power supply voltage greater than or equal ± 15 V dc, the AD215 may supply up to ± 15 mA from the isolated power supplies. 10Voltages less than 14.25 V dc may cause the AD215 to cease operating properly. Voltages greater than ± 17.5 V dc may damage the internal components of the AD215 and consequently should not be used. Specifications subject to change without notice. WARNING! ESD SENSITIVE DEVICE 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 AD215 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.

Figure 1. Functional Block Diagram

1 IN+ Noninverting Input

2 IN COM Input Common

3 IN– Inverting Input

4 FB Amplifier Feedback

36 TRIM Output Offset Trim Adjust

37 OUT LO Output Low

38 OUT HI Output High

43 PWR RTN ± 15 V dc Power Supply Common

frequencies of 120 kHz or less. then rectified and filtered for use as the isolated power supply. tion or signal conditioning is required. the designer flexibility to adjust for any offset as desired.

Figure 8. Output Response to Full-Scale Step Input Figure 9. ±VISO Supply Ripple vs. Load

15.0 VISO – ±V

Figure 10. ±VISO Supply Voltage vs. Load

Figure 23. Strain Gage Signal Conditioning Application

REV. 0–12– OUTLINE DIMENSIONS Dimensions shown in inches and (mm). AD215 SIP PACKAGE 0.094 (2.4) 0.015 (0.4) 2.480 (63.0) MAX 0.815 (20.7) 0.010 (0.25) 0.165 (4.2) 0.135 (3.4) 0.840 (21.4) MAX 0.325 (8.3) MAX 36 38 42 44 BOTTOM VIEW OF FOOTPRINT 0.712 (18.2) 4 62 3 5 0.712 (18.2) 0.1 (2.5) 0.11 (2.8) 0.11 (2.8) 0.2 (5.1) 0.1 (2.5) 0.325 (8.3) MAX 0.022 (0.56) 1.50 (38.1) 0.250 (6.4) 2.15 (54.6) 0.05 (1.3) 0.1 (2.5) TINNING MAY ADD UP TO 3 mils (0.003") TO THESE DIMENSIONS. CL C2134–20–4/96PRINTED IN U.S.A.