Analog Devices Inc. LTC6373HDFM#TRPBF

Overview

LTC6373HDFM#TRPBF from Analog Devices is a 36 V fully-differential programmable-gain instrumentation amplifier with 25 pA max input bias current, ±4.5 V to ±18 V supply range, 0.015% max gain error, 103 dB min CMRR at G = 16, and 4 MHz −3 dB bandwidth at G = 16 - used in high-precision data acquisition systems interfacing ground-referenced differential sensors to 5 V ADCs.

For engineers reviewing the LTC6373HDFM#TRPBF datasheet, LTC6373HDFM#TRPBF pinout, LTC6373HDFM#TRPBF application, or LTC6373HDFM#TRPBF equivalent, key selection considerations include differential output drive capability for SAR/ΣΔ ADCs, pin-programmable gain (0.25–16 V/V), adjustable VOCM, low 8 nV/√Hz input noise at G = 16, and operation across −40°C to +105°C.

Technical Context

The LTC6373HDFM#TRPBF implements a monolithic 3-op-amp topology with laser-trimmed internal resistor arrays enabling precise gain settings (G = 0.25, 0.5, 1, 2, 4, 8, 16 V/V) via 3-bit parallel interface (A2–A0) and shutdown mode. Its gain-bandwidth behavior deviates from classical voltage-feedback amplifiers: bandwidth increases with gain (e.g., 4 MHz at G = 16 vs. 7.5 MHz at G = 0.25), achieved through per-gain frequency compensation.

It delivers fully differential outputs with independently adjustable common-mode voltage via VOCM pin, supports single-ended-to-differential conversion, and features high input impedance (>5 TΩ differential/common-mode), 1.7 μV/°C max input offset drift at G = 16, and rail-to-rail output swing capability under load.

Key Specifications

Pinout & Package

Package: 12-lead 4 mm × 4 mm DFN (LFCSP) with exposed pad connected to V–; rated for −40°C to +105°C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar instrumentation amplifier applications.

Compared with AD8421ARMZ and INA828IDRCT, the LTC6373HDFM#TRPBF uniquely combines pin-programmable attenuation/amplification (0.25–16×), fully differential outputs, and VOCM control - enabling direct, calibrated ADC interface without additional active components or layout complexity.

Availability

LTC6373HDFM#TRPBF is available at Aetrix Electronics and suitable for data acquisition systems, biomedical instrumentation, and test and measurement equipment requiring stable component supply, long-term lifecycle assurance, and guaranteed −40°C to +105°C performance.

Supply support for LTC6373HDFM#TRPBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, communications, automotive, and healthcare markets since 1965.

The LTC6373HDFM#TRPBF belongs to Analog Devices' precision instrumentation amplifier product line, designed specifically for high-fidelity signal conditioning in data acquisition and sensor interface applications demanding low noise, low drift, and flexible gain architecture.

FAQ

What gain settings does the LTC6373HDFM#TRPBF support, and how are they selected?

The LTC6373HDFM#TRPBF supports seven discrete gain settings: 0.25, 0.5, 1, 2, 4, 8, and 16 V/V, selected via a 3-bit parallel interface using pins A2, A1, and A0 referenced to DGND. The eighth state (A2=A1=A0=high) activates shutdown mode, reducing supply current to 220 µA. Each gain setting is implemented with laser-trimmed internal resistors to ensure accuracy and stability across temperature.

Can the LTC6373HDFM#TRPBF drive a differential-input ADC directly?

Yes, the LTC6373HDFM#TRPBF is explicitly designed for direct interface to differential-input ADCs. Its fully differential outputs provide matched, low-impedance drive with <−75 dB balance error, and the VOCM pin allows precise adjustment of output common-mode voltage to match the ADC's input requirement - eliminating need for external level-shifting or passive resistor networks.

What is the maximum input bias current specification for the LTC6373HDFM#TRPBF, and why does it matter?

The LTC6373HDFM#TRPBF has a maximum input bias current of 25 pA at 25°C, rising to 600 pA over −40°C to +105°C. This ultra-low value prevents loading errors in high-impedance sensor circuits (e.g., piezoresistive bridges, pH electrodes, or photodiode transimpedance stages), preserving signal fidelity and minimizing offset drift caused by source resistance imbalance.

How does the LTC6373HDFM#TRPBF handle common-mode rejection across gain and temperature?

The LTC6373HDFM#TRPBF achieves ≥103 dB CMRR at G = 16 and DC–60 Hz with 1 kΩ source imbalance; CMRR remains ≥98 dB over −40°C to +105°C at G = 16. This performance stems from its monolithic 3-op-amp architecture with tightly matched internal resistors and CMOS input stage, ensuring consistent noise and interference rejection in electrically noisy industrial environments.

Is the LTC6373HDFM#TRPBF compatible with single-ended input sources?

Yes, the LTC6373HDFM#TRPBF accepts both fully differential and single-ended input signals. When driven single-ended (e.g., one input grounded), its architecture maintains high CMRR and low distortion due to internal resistor matching. Application Note AN-1347 confirms proper layout techniques - including symmetric trace routing and guard rings - to preserve performance in single-ended configurations.