Analog Devices Inc. LT3040IMSE#TRPBF

Overview

LT3040IMSE#TRPBF from Analog Devices is a precision voltage output reference/DAC buffer IC delivering ultralow noise (1.2 µV_RMS, 10 Hz–100 kHz), ultrahigh PSRR (73 dB at 1 MHz), and 200 mA source current in a thermally enhanced 12-lead MSOP package. It operates from 1.8 V to 20 V input, supports rail-to-rail 0 V to 15 V output, and features programmable current limit, FAULT flag, and fast start-up - ideal for powering high-precision data converters and voltage references.

For engineers reviewing the LT3040IMSE#TRPBF datasheet, LT3040IMSE#TRPBF pinout, LT3040IMSE#TRPBF application, or LT3040IMSE#TRPBF equivalent, key selection criteria include its 125 µV input offset, 350 mV dropout at 200 mA, 4.7 µF minimum ceramic output capacitor requirement, reverse supply protection, and thermal hysteresis-limited shutdown behavior.

Technical Context

The LT3040IMSE#TRPBF employs a dual-input-pair architecture (PNP/NPN switchover at ~0.9 V) enabling true rail-to-rail output operation while maintaining sub-µV-level offset stability across temperature and load. Its error amplifier integrates bias current cancellation for VIN voltages ≥100 mV and uses internal foldback current limiting activated above V₊–V_OUT = 12 V.

PSRR performance is frequency- and region-dependent: NPN region delivers 117 dB at 120 Hz and 73 dB at 1 MHz; PNP region achieves 104 dB at 120 Hz and 67 dB at 1 MHz. Fast start threshold is 100 mV (turn-on) with 7 mV hysteresis, and EN/UV pin has 1.24 V nominal trip point and 170 mV hysteresis.

Key Specifications

Pinout & Package

LT3040IMSE#TRPBF is housed in a 12-lead plastic MSOP package (MSE) with exposed pad (Pin 13) soldered to PCB ground for thermal management (θ_JA = 28°C/W). Pin count, layout, and thermal design are optimized for high-PSRR analog signal integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision reference buffer applications.

Compared with LT3042IMSE#TRPBF and ADP7182ARDZ-3.3-R7, the LT3040IMSE#TRPBF uniquely combines rail-to-rail 0–15 V output adjustability, FAULT flag visibility, and 1.2 µV_RMS noise across a 1.8–20 V input range - making it the only option supporting both wide-supply instrumentation and real-time fault monitoring.

Availability

LT3040IMSE#TRPBF is available at Aetrix Electronics and suitable for high-precision data converters, voltage reference buffering, low-noise instrumentation, and portable test equipment requiring stable component supply across industrial temperature ranges.

Supply support for LT3040IMSE#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, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision, industrial, communications, and automotive markets.

The LT3040 belongs to ADI's Ultralow-Noise Linear Regulator family, engineered specifically for powering noise-sensitive analog signal chains - including high-resolution ADCs, DACs, and precision references - where PSRR, output noise, and DC accuracy are critical.

FAQ

What is the minimum output capacitor required for stable operation of the LT3040IMSE#TRPBF?

The LT3040IMSE#TRPBF requires a minimum 4.7 µF ceramic output capacitor for guaranteed stability across all operating conditions. This value is specified in the Absolute Maximum Ratings and Typical Application sections of the datasheet. Using lower capacitance or non-ceramic types may cause oscillation or degraded PSRR and noise performance. The capacitor must be placed close to the OUT and GND pins with low-inductance layout.

Does the LT3040IMSE#TRPBF support rail-to-rail output voltage operation?

Yes, the LT3040IMSE#TRPBF supports true rail-to-rail output from 0 V to 15 V. This is achieved through an internal architecture that automatically switches between PNP and NPN input differential pairs near 0.9 V, as confirmed in Note 19 and Figure G09 of the datasheet. Output regulation remains stable across the full range, with consistent noise, PSRR, and load regulation independent of VIN.

How does the FAULT pin on the LT3040IMSE#TRPBF behave during overcurrent events?

The FAULT pin on the LT3040IMSE#TRPBF is an open-drain output that pulls low (<200 mV at 100 µA sink) when an overcurrent, thermal shutdown, or undervoltage lockout condition occurs. It remains asserted until the fault condition clears and the device re-enables. The FAULT pin is electrically isolated from other pins and includes internal clamping to prevent damage from transients.

Can the LT3040IMSE#TRPBF be paralleled with another LT3040IMSE#TRPBF for higher output current or lower noise?

Yes, the LT3040IMSE#TRPBF is explicitly designed to be paralleled - as stated in its FEATURES list - to achieve both lower output noise (via averaging) and higher total output current. When paralleling, each device requires individual ILIM resistors and matched layout to ensure current sharing. The FAULT pins should be wire-OR'd, and the FS pins tied together to maintain synchronized fast start-up.

What is the quiescent current of the LT3040IMSE#TRPBF in shutdown mode?

The LT3040IMSE#TRPBF draws less than 1 µA quiescent current in shutdown mode, measured with EN/UV = 0 V and V+ = 6 V over the full –40°C to 125°C temperature range. This ultra-low shutdown current is verified in the Electrical Characteristics table (page 4) and supports battery-powered applications requiring multi-year shelf life and minimal standby drain.