HCPL-7851

Instrumentation, Op Amps, Buffer Amps Overview

The HCPL-7851 is a Class H hermetically sealed optically isolated amplifier manufactured by Broadcom Limited. It integrates a Sigma-Delta modulator and DAC for high-reliability signal isolation. Key electrical parameters include a 100 kHz bandwidth, 1500 Vrms insulation voltage, and 8 V/V gain. The device operates on a single 4.5 V to 5.5 V supply with a typical current of 15.5 mA. Input specifications feature a ±200 mV dynamic range, 600 µV input offset voltage, and 570 nA bias current. It provides 69 dB CMRR and maintains performance across a -55°C to +125°C temperature range within an 8-pin ceramic DIP package.

Instrumentation, Op Amps, Buffer Amps Feature Summary

• Hermetically sealed Class H ceramic DIP construction for high reliability in harsh environments
• Sigma-Delta modulation architecture enabling high common-mode transient immunity
• Integrated analog-to-digital and digital-to-analog conversion for precise signal isolation

Instrumentation, Op Amps, Buffer Amps Applications

• Motor controller current sensing
• Variable frequency drive (VFD) monitoring
• Industrial automation systems
• Military and aerospace instrumentation
• Medical equipment signal isolation

Instrumentation, Op Amps, Buffer Amps Procurement Notes

Verify the specific ordering suffix to confirm package type and qualification level. Ensure the procurement matches the required Class H military standard if applicable. Confirm RoHS compliance status as it varies by manufacturing batch. Check datasheet revisions for any updates to mechanical dimensions or electrical limits before finalizing orders.

Instrumentation, Op Amps, Buffer Amps Selection Notes

Select this component when high isolation voltage and wide operating temperature are critical. The 100 kHz bandwidth suits moderate-speed isolation applications. Verify that the 8 V/V fixed gain meets system requirements without external amplification. Consider the 1500 Vrms isolation barrier for safety-critical designs. Ensure the single-supply operation aligns with available power rails.

Instrumentation, Op Amps, Buffer Amps Part Context

Part of the HCPL series of optically isolated amplifiers from Broadcom. Designed for applications requiring robust signal integrity across isolation barriers. Utilizes proprietary internal shielding to enhance noise rejection. Represents a specialized solution for precision analog signal transmission in electrically noisy environments.

Instrumentation, Op Amps, Buffer Amps Replacement Considerations

HCPL-7851#100 is a documented variant within the same family.