Analog Devices Inc. LTC2911IDDB-3#TRMPBF

Overview

LTC2911IDDB-3#TRMPBF from Analog Devices (formerly Linear Technology) is a precision triple supply monitor IC with integrated power-fail comparator and latched reset control. It monitors 3.3V (V1), 1.8V (V2), and an adjustable input (ADJ) with ±1.5% threshold accuracy over –40°C to 85°C, supports internal 200ms reset timeout, and operates down to 0.5V V_CC. Used in notebook computers and industrial embedded systems for reliable power sequencing and early brownout warning.

For engineers reviewing the LTC2911IDDB-3#TRMPBF datasheet, LTC2911IDDB-3#TRMPBF pinout, LTC2911IDDB-3#TRMPBF application, or LTC2911IDDB-3#TRMPBF equivalent, key selection criteria include its 3.3V/1.8V dual fixed thresholds, 0.5V ADJ/PFI trip point, latch-enabled margin testing, ultralow 30µA quiescent current, and DFN-8 (3mm × 2mm) package compatibility with space-constrained PCB layouts.

Technical Context

The LTC2911IDDB-3#TRMPBF implements three independent voltage comparators - one for V1 (3.3V nominal), one for V2 (1.8V nominal per -3 variant), and one for ADJ (0.5V threshold) - all featuring 1.5% accuracy across temperature and built-in glitch filtering. Its PFI comparator provides 500mV falling-edge / 515mV rising-edge hysteresis for noise-immune power-fail detection.

Reset assertion is controlled via TMR pin configuration: tying TMR to V1 enables internal 200ms timeout; connecting CTMR to GND sets external timeout (e.g., 20ms with 2.2nF); pulling TMR to GND latches RST state. Internal V_CC derives from the higher of V1 or V2, enabling operation during asymmetric supply ramp-up.

Key Specifications

Pinout & Package

Package: 8-lead (3mm × 2mm) plastic DFN (DDB) with exposed pad (Pin 9, GND). Thermal resistance θ_JA = 76°C/W enables high-density thermal management without heatsinking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple-supply monitoring applications.

Compared with MAX6313US33D3+T and TPS3808G33DBVR, the LTC2911IDDB-3#TRMPBF uniquely integrates 3.3V/1.8V/adjustable monitoring, PFI-based early warning, and latch-enabled margining in one DFN-8 package-reducing component count, PCB area, and validation effort for multi-rail systems.

Availability

LTC2911IDDB-3#TRMPBF is available at Aetrix Electronics and suitable for notebook computers, industrial PLCs, and automotive infotainment modules requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LTC2911IDDB-3#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, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors.

The LTC2911 family was designed specifically for precision multi-rail power monitoring in space-constrained, thermally demanding applications such as servers, portable computing, and automotive electronics.

FAQ

What is the exact V2 threshold voltage for LTC2911IDDB-3#TRMPBF?

The LTC2911IDDB-3#TRMPBF has a nominal V2 threshold of 1.8V, implemented as 1.683V (–6.5%) with ±1.5% accuracy over –40°C to +85°C. This value is confirmed in the Electrical Characteristics table (VRT18 parameter) and applies specifically to the -3 variant, which matches the "3" suffix in the part number.

Does LTC2911IDDB-3#TRMPBF support external reset timeout configuration?

Yes, LTC2911IDDB-3#TRMPBF supports both internal and external reset timeout. Connecting the TMR pin to V1 enables the factory-trimmed 200ms timeout. For custom delays, connect a capacitor (e.g., 2.2nF) between TMR and GND to achieve ~20ms; timing follows CTMR = tRST × 106.5 pF/ms.

How does the PFI input function in LTC2911IDDB-3#TRMPBF?

The PFI input in LTC2911IDDB-3#TRMPBF monitors a system supply via resistive divider and compares it to a 500mV falling-edge / 515mV rising-edge threshold. When PFI falls below 500mV, PFO pulls low to provide early power-fail warning-typically used to trigger non-maskable interrupts or initiate controlled shutdown before RST asserts.

Can LTC2911IDDB-3#TRMPBF operate with only the V1 supply present?

Yes, LTC2911IDDB-3#TRMPBF can operate with only V1 powered. For the -3 variant, internal V_CC is derived from the greater of V1 and V2; if V2 is unconnected or grounded, V1 alone powers the device. V1 must be ≥3.036V to guarantee proper reset assertion, and requires a 0.1µF bypass capacitor.

What is the purpose of the TMR pin's latch mode in LTC2911IDDB-3#TRMPBF?

The TMR pin's latch mode in LTC2911IDDB-3#TRMPBF allows the RST output state to be frozen independently of input conditions. Pulling TMR to GND latches the current RST level-enabling margin testing at voltages below threshold without triggering spurious resets, then releasing TMR restores normal monitoring after setup/hold timing.