Analog Devices Inc. LTC2911IDDB-5#TRPBF

Overview

LTC2911IDDB-5#TRPBF from Analog Devices (formerly Linear Technology) is a precision triple supply monitor IC with power-fail comparator and latched reset functionality. It monitors V1 (3.3V), V2 (adjustable), and ADJ (0.5V threshold) inputs with ±1.5% threshold accuracy over –40°C to 85°C, supports internal 200ms or external capacitor–programmable reset timeout, and delivers ultralow-voltage operation down to VCC = 0.5V - used in industrial embedded systems for reliable power sequencing and controlled shutdown.

For engineers reviewing the LTC2911IDDB-5#TRPBF datasheet, LTC2911IDDB-5#TRPBF pinout, LTC2911IDDB-5#TRPBF application, or LTC2911IDDB-5#TRPBF equivalent, key selection criteria include its adjustable dual-supply monitoring capability (V2 and ADJ both configurable), PFI-based early-warning power-fail signaling, TMR latch mode for margin testing, and DFN-8 (3mm × 2mm) package compatibility with space-constrained PCB layouts.

Technical Context

The LTC2911IDDB-5#TRPBF implements three independent voltage comparators: V1 fixed at 3.3V (–6.5% trip = 3.086V), V2 as high-impedance adjustable input (nominal 0.5V threshold), and ADJ also with 0.5V threshold - enabling dual-resistive-divider configuration for two independent supply rails. Its internal VCC is derived solely from V1, unlike other variants that select between V1/V2.

It integrates a dedicated power-fail comparator (PFI → PFO) with 500mV falling / 515mV rising thresholds (3% hysteresis), plus TMR-controlled latch mode that holds RST low/high independently of input transitions. Reset assertion timing includes 8–80µs propagation delay and selectable timeout (200ms internal or 15–27ms external with 2.2nF).

Key Specifications

Pinout & Package

Package: 8-lead (3mm × 2mm) plastic DFN with exposed pad (Pin 9), rated TJMAX = 150°C, θJA = 76°C/W. Exposed pad may be left open or connected to GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G33DBVR and MAX6369KA+T, the LTC2911IDDB-5#TRPBF uniquely combines dual adjustable monitoring (V2 + ADJ), integrated PFI/PFO early-warning path, and DFN-8 thermal efficiency - making it the only option supporting complex multi-rail margin testing and controlled shutdown in compact industrial designs.

Availability

LTC2911IDDB-5#TRPBF is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and medical portable equipment requiring stable component supply, long-term lifecycle support, and guaranteed parametric performance across –40°C to 85°C.

Supply support for LTC2911IDDB-5#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 industrial, automotive, communications, and healthcare markets.

The LTC2911 family was designed by Linear Technology (acquired by ADI in 2017) specifically for precision power monitoring in mission-critical embedded systems - emphasizing ±1.5% threshold accuracy, ultralow-voltage operation, and flexible reset timing control.

FAQ

What is the exact reset threshold voltage for V1 on the LTC2911IDDB-5#TRPBF?

The V1 reset threshold for LTC2911IDDB-5#TRPBF is 3.086V (3.3V – 6.5%), with ±1.5% accuracy over –40°C to 85°C - guaranteed between 3.036V and 3.135V. This tight tolerance prevents false resets during supply ripple or temperature variation, ensuring reliable operation in industrial environments where power quality is marginal.

How does the LTC2911IDDB-5#TRPBF differ from other LTC2911 variants like LTC2911-2 or LTC2911-3?

The LTC2911IDDB-5#TRPBF is the LTC2911-5 variant: V2 is an adjustable 0.5V-threshold input (like ADJ), unlike LTC2911-2 (2.5V fixed) or LTC2911-3 (1.8V fixed). This enables dual adjustable rail monitoring. Its marking "LFPP", DFN-8 package, and I-grade (–40°C to 85°C) confirm this identity per Linear's Product Selection Guide.

Can the LTC2911IDDB-5#TRPBF monitor two different adjustable supplies simultaneously?

Yes - the LTC2911IDDB-5#TRPBF supports simultaneous monitoring of two user-defined supplies: V2 and ADJ both feature 0.5V nominal thresholds with ±7.5mV accuracy. Each accepts a resistive divider, allowing independent configuration (e.g., 1.2V on V2, 5V on ADJ), eliminating need for a second supervisor IC in multi-rail systems.

What is the purpose of the TMR pin on the LTC2911IDDB-5#TRPBF, and how is it used?

The TMR pin on LTC2911IDDB-5#TRPBF controls reset timeout and latch mode: tying to V1 enables internal 200ms timeout; connecting to GND latches RST state (freezing high/low output) for margin testing; leaving open yields ~400µs timeout. This flexibility supports both production validation and field-deployed reliability requirements.

Does the LTC2911IDDB-5#TRPBF require external pull-up resistors on RST and PFO outputs?

The LTC2911IDDB-5#TRPBF provides weak internal pull-ups to V1 (~29µA at 3.3V), sufficient for light loads. However, external pull-ups are recommended when driving heavy capacitive loads or when VOH > V1 is needed (e.g., interfacing with 5V-tolerant inputs). The datasheet explicitly notes external resistors improve rise time and voltage margin.