AD847AR

Instrumentation, Op Amps, Buffer Amps Overview

The AD847AR is a high-speed, low-power monolithic operational amplifier manufactured by Analog Devices Inc. in an 8-lead Small Outline (SOIC) package. It operates within a supply voltage range of ±4.5 V to ±18 V and draws a typical quiescent current of 5.3 mA at ±15 V. The device features a unity-gain bandwidth of 50 MHz and a slew rate of 300 V/µs. Key electrical specifications include a maximum input offset voltage of 1 mV, a minimum common-mode rejection ratio of 78 dB, and a short-circuit output current of 32 mA.

Instrumentation, Op Amps, Buffer Amps Feature Summary

• Internally compensated for unity gain stability while driving any capacitive load
• High open-loop gain with low input offset voltage for excellent DC performance
• Low power consumption suitable for high-density applications
• Enhanced replacement for legacy LM6361 and HA2544 amplifiers

Instrumentation, Op Amps, Buffer Amps Applications

• Video instrumentation and imaging equipment
• High-speed cable drivers
• Input buffers for flash A/D converters
• Output buffers for high-speed digital-to-analog converters

Instrumentation, Op Amps, Buffer Amps Procurement Notes

Verify the specific suffix 'AR' corresponds to the SOIC-8 package and -40°C to +85°C temperature range. Confirm that the ordering guide matches the required processing standard, as military-grade variants like the AD847SQ/883B utilize different packaging and qualification protocols. Ensure compatibility with existing PCB footprints for the R-8 outline.

Instrumentation, Op Amps, Buffer Amps Selection Notes

Select this component when a balance of high speed and low power is required. The AD847AR offers superior settling time compared to general-purpose amplifiers. Consider the dual-channel AD827 if multiple channels are needed in an 8-pin footprint. Evaluate the AD847JN if operation is restricted to commercial temperatures and lower costs are prioritized over extended ranges.

Instrumentation, Op Amps, Buffer Amps Part Context

The AD847 series represents a breakthrough in high-speed amplifier technology using Analog Devices' proprietary complementary bipolar process. This architecture allows for pnp and npn transistors with transition frequencies in the 600 MHz to 800 MHz region. The family includes plastic DIP, SOIC, Cerdip packages, and die forms, catering to diverse industrial and aerospace requirements.

Instrumentation, Op Amps, Buffer Amps Replacement Considerations

Officially documented replacements include the LM6361, HA2544, HA2520/2/5, and EL2020. Designers should verify pinout compatibility and ensure that the replacement meets the specific settling time and capacitive drive requirements of the original circuit design.

Instrumentation, Op Amps, Buffer Amps FAQ

How does the AD847 maintain stability when driving capacitive loads?

The AD847 utilizes internal compensation capacitance provided by junction capacitances in the gain stage. Additionally, a capacitor in the output stage mitigates capacitive load effects, ensuring the amplifier remains stable even as load capacitance increases.

What is the recommended feedback resistor value for optimal performance?

Feedback resistors should be less than 5 kΩ to prevent the time constant formed with summing junction capacitance from limiting performance. If larger resistors are necessary, a small feedback capacitor may be used to compensate for input capacitances.