LT1787IS8

Instrumentation, Op Amps, Buffer Amps Overview

The LT1787IS8 is a micropower precision high-side current sense amplifier manufactured by Analog Devices. It operates from a total supply voltage of 2.5V to 36V and features a fixed gain of 8 V/V. The device provides bidirectional current sensing with an input offset voltage of 40µV (typical) and a maximum of 75µV. It delivers over 12-bit dynamic range resolution and draws only 60µA of operating current. The part includes provisions for input noise filtering via FIL+ and FIL– pins and offers a power supply rejection ratio exceeding 120dB.

Instrumentation, Op Amps, Buffer Amps Feature Summary

• Bidirectional high-side current monitoring capability
• Micropower operation with ultralow input offset voltage
• Fixed internal gain of eight for simplified circuit design
• Integrated input noise filtering terminals

Instrumentation, Op Amps, Buffer Amps Applications

• Battery monitoring in portable devices
• Power management systems
• Portable test and measurement equipment
• Battery-operated system protection

Instrumentation, Op Amps, Buffer Amps Procurement Notes

Verify the specific suffix IS8 corresponds to the industrial temperature grade (-40°C to 85°C) and SOIC-8 package. Confirm RoHS compliance status through official manufacturer documentation or authorized distributor declarations prior to procurement. Ensure the ordering number matches the required performance specifications for the target application environment.

Instrumentation, Op Amps, Buffer Amps Selection Notes

Select the LT1787IS8 when single-supply operation up to 36V is required alongside bidirectional sensing capabilities. This variant is suitable for applications needing precise low-voltage drop measurements without external gain resistors. Consider the fixed 8V/V gain and 20kΩ output resistor for direct interfacing with standard analog-to-digital converters or microcontroller inputs.

Instrumentation, Op Amps, Buffer Amps Part Context

The LT1787 series comprises precision current sense amplifiers designed for monitoring current flow into or out of batteries and other elements. The IS8 designation indicates the Industrial temperature grade version housed in an 8-lead SOIC package. It belongs to a family that includes variants like the LT1787HV for higher voltage operations up to 60V.

Instrumentation, Op Amps, Buffer Amps Replacement Considerations

Direct replacements within the same family include LT1787CS8 for commercial temperature grades or LT1787HVIS8#PBF for high-voltage bidirectional sensing up to 60V. Verify pin compatibility and electrical characteristics against the original datasheet requirements before substitution.

Instrumentation, Op Amps, Buffer Amps FAQ

How is bidirectional current sensing achieved?

Bidirectional sensing is enabled by connecting the VBIAS pin to a bias voltage or ground, allowing the VOUT signal to swing above or below VBIAS depending on the direction of current flow through the sense resistor.

What is the purpose of the FIL+ and FIL– pins?

These pins allow for input noise filtering. Connecting a capacitor between them creates a single-pole low-pass filter to attenuate high-frequency signals and prevent aliasing errors during sampling.