Analog Devices Inc. LTC2920-1IS5#TRMPBF

Overview

LTC2920-1IS5#TRMPBF from Analog Devices (formerly Linear Technology) is a single-channel precision power supply voltage margining controller IC designed to inject calibrated current into the feedback node of DC/DC converters or power modules for automated high- and low-voltage margin testing. It delivers ±5 μA to ±2 mA margin current with <0.4% typical accuracy, operates from 2.3V to 6V V_CC, and supports 0.6V to (V_CC – 0.6V) output compliance - enabling use in 3.3V and 5V rail validation during PCB production test.

For engineers reviewing the LTC2920-1IS5#TRMPBF datasheet, LTC2920-1IS5#TRMPBF pinout, LTC2920-1IS5#TRMPBF application, or LTC2920-1IS5#TRMPBF equivalent, this page provides verified functional context, validated pin-level circuit roles, confirmed margining accuracy vs. voltage compliance trade-offs, and real-world substitution guidance for industrial power test systems requiring stable, temperature-rated (-40°C to +85°C) margining control.

Technical Context

The LTC2920-1IS5#TRMPBF implements a trimmed internal voltage reference and programmable current source/sink architecture, where margin current magnitude is set by a single external resistor (R_SET) connected to RS1, offering 400:1 range via dual-scale operation (low range: 5–167 μA; high range: 150 μA–2 mA). Its three-state IN1 control pin (logic high = sink, logic low = source, floating = high-Z) enables precise sequencing of up/down margin events without external logic.

It features wide output compliance (0.6V ≤ V_MARGIN ≤ V_CC – 0.6V), 15–100 μs turn-on/off delay, sub-microsecond rise/fall times, and leakage-limited IM1 output (<100 nA off-state), ensuring minimal interference with sensitive feedback networks while maintaining accuracy across its full operating temperature range (–40°C to +85°C).

Key Specifications

Pinout & Package

Package: 5-lead SOT-23 (ThinSOT™), 1.6mm × 2.9mm footprint, rated for TJ_MAX = 125°C, θ_JA = 250°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power supply margining applications.

Compared with MAX5082EUA+ and TPS54620RGYR, the LTC2920-1IS5#TRMPBF offers superior margining accuracy (<0.4% vs. ±1.5%), integrated reference, and true bi-directional current injection - making it the only option suitable for ATE-grade validation where traceable, sub-0.5% voltage deviation is required.

Availability

LTC2920-1IS5#TRMPBF is available at Aetrix Electronics and suitable for automated PCB production testing, DC/DC converter validation, and industrial power module margining requiring stable component supply across extended temperature ranges and long-life manufacturing programs.

Supply support for LTC2920-1IS5#TRMPBF 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 (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving aerospace, industrial, communications, and automotive markets.

The LTC2920 family was designed specifically for automated power supply margining in high-reliability manufacturing and field maintenance - emphasizing precision current sourcing/sinking, minimal external components, and robust operation across industrial temperature ranges.

FAQ

What is the primary function of the LTC2920-1IS5#TRMPBF in power supply testing?

The LTC2920-1IS5#TRMPBF is a single-channel voltage margining controller that precisely sources or sinks current into the feedback node of DC/DC converters or power modules to induce controlled upper and lower voltage deviations. Its core function is enabling automated, repeatable validation of power rail stability at specification limits - a critical step in high-reliability PCB production test and preventative maintenance. The LTC2920-1IS5#TRMPBF achieves this using an internal trimmed reference and single-resistor current programming, eliminating need for external DACs or precision op-amps.

How does the LTC2920-1IS5#TRMPBF achieve its <0.4% margining accuracy?

The LTC2920-1IS5#TRMPBF achieves <0.4% typical margining accuracy through a factory-trimmed on-board voltage reference and matched internal current mirror circuitry. This eliminates dependency on external reference components and minimizes process- and temperature-induced gain errors. Accuracy is further maintained across –40°C to +85°C via on-die temperature compensation and tight matching between the reference and current-setting paths. The LTC2920-1IS5#TRMPBF datasheet specifies worst-case I-Grade accuracy as ±25% only at the lowest current subrange (5–30 μA), confirming that <0.4% applies to typical operational conditions (e.g., 100 μA–2 mA).

Can the LTC2920-1IS5#TRMPBF be used with power supply modules that have a trim pin instead of a feedback pin?

Yes, the LTC2920-1IS5#TRMPBF is explicitly designed for use with "brick"-type power supply modules featuring analog trim pins. It replaces discrete trim resistors and mechanical relays by injecting calibrated current directly into the trim pin - leveraging the typically linear relationship between trim current and output voltage change. Application Note 2920-1/2 details measurement procedures to derive the module-specific K_TRIM constant and select appropriate R_SET. The LTC2920-1IS5#TRMPBF's wide output compliance (0.6V to V_CC – 0.6V) ensures compatibility with common trim pin voltage ranges.

What are the critical power sequencing requirements for the LTC2920-1IS5#TRMPBF?

The LTC2920-1IS5#TRMPBF requires V_CC to be powered no later than the controlled power supply turns on - otherwise, undesired fault current can flow into the IM1 pin, causing overvoltage damage. Per datasheet guidelines, V_CC must remain ≥0.2V above the highest IM1 voltage at all times. Recommended solutions include connecting V_CC directly to the margined supply's VIN or VOUT (if within 2.3–6V), or using a Schottky diode from a shared bias rail. These constraints are mandatory for safe operation and are documented in the "Preventing Potential Power Supply Overvoltages" section of the LTC2920-1IS5#TRMPBF datasheet.

Is the LTC2920-1IS5#TRMPBF pin-compatible with the dual-channel LTC2920-2IMS8?

No, the LTC2920-1IS5#TRMPBF is not pin-compatible with the LTC2920-2IMS8. The LTC2920-1IS5#TRMPBF uses a 5-pin SOT-23 (ThinSOT™) package with pins V_CC, GND, IM1, RS1, and IN1. The LTC2920-2IMS8 uses an 8-pin MSOP package with two independent channels (IN1/RS1/IM1 and IN2/RS2/IM2), plus shared V_CC and GND. There is no mechanical or electrical pin mapping between them - they are distinct products targeting single- versus dual-rail margining. Migration requires PCB redesign and firmware adaptation to manage two control signals.