Analog Devices Inc. LTC2911ITS8-5#TRMPBF

Overview

LTC2911ITS8-5#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 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 LTC2911ITS8-5#TRMPBF datasheet, LTC2911ITS8-5#TRMPBF pinout, LTC2911ITS8-5#TRMPBF application, or LTC2911ITS8-5#TRMPBF 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 TSOT-23-8 package compatibility with space-constrained PCB layouts.

Technical Context

The LTC2911ITS8-5#TRMPBF implements three independent voltage comparators: one fixed 3.3V monitor on V1, one high-impedance adjustable input on V2 (nominal 0.5V threshold), and one on ADJ (also 0.5V threshold). Its internal VCC is derived solely from V1, unlike other variants that select between V1/V2 - enabling stable operation even when V2 is below V1.

It features a dedicated PFI/PFO path with 500mV falling-edge and 515mV rising-edge thresholds (3% hysteresis), plus TMR pin logic supporting three modes: external capacitor timeout, internal 200ms timeout (TMR tied to V1), and latch mode (TMR pulled to GND). Glitch immunity is ensured via input filtering and propagation delays under 80µs across all comparators.

Key Specifications

Pinout & Package

Package: 8-lead TSOT-23 (TS8), 3mm × 1.75mm footprint, exposed pad optional, θJA = 195°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6369KA+T and TPS3808G33DBVR, the LTC2911ITS8-5#TRMPBF uniquely supports two fully adjustable monitoring inputs (V2 and ADJ) plus PFI-based early-warning signaling in a single TSOT-23-8 package, enabling compact, flexible, and noise-immune power supervision for complex multi-rail systems.

Availability

LTC2911ITS8-5#TRMPBF is available at Aetrix Electronics and suitable for industrial PLCs, automotive body control modules, network equipment hot-swap controllers, and medical imaging power sequencing requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.

Supply support for LTC2911ITS8-5#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 digital signal processing semiconductors.

The LTC2911 family was designed specifically for precision multi-rail power monitoring in industrial, automotive, and communications infrastructure - emphasizing threshold accuracy, ultralow-voltage operation, and configurable fault response.

FAQ

What is the exact reset threshold voltage for the V1 pin on the LTC2911ITS8-5#TRMPBF?

The V1 pin on the LTC2911ITS8-5#TRMPBF has a guaranteed reset threshold of 3.086V ±1.5% over the full –40°C to +85°C operating range, corresponding to a –6.5% deviation from 3.3V. This tight tolerance ensures reliable detection of 3.3V supply undervoltage without false triggering due to temperature drift or manufacturing variation - a key specification confirmed in the Electrical Characteristics table of the official datasheet.

How does the LTC2911ITS8-5#TRMPBF differ from other LTC2911 variants like the -1 or -2 versions?

The LTC2911ITS8-5#TRMPBF is the LTC2911-5 variant, meaning its V2 pin functions as a high-impedance adjustable input (0.5V threshold), unlike the LTC2911-1 (5V fixed) or LTC2911-2 (2.5V fixed). It derives internal VCC exclusively from V1, supports dual adjustable monitoring (V2 and ADJ), and uses TSOT-23-8 packaging - making it uniquely suited for custom multi-rail systems where fixed thresholds are insufficient.

Can the LTC2911ITS8-5#TRMPBF monitor a 1.2V supply, and if so, how?

Yes - the LTC2911ITS8-5#TRMPBF can monitor a 1.2V supply using either the ADJ or V2 pin, both of which have a 0.5V nominal threshold. A resistive divider (e.g., 100kΩ + 140kΩ) scales the 1.2V rail to 0.5V at the input. The datasheet specifies ADJ input bias current ≤±40nA (H-grade), ensuring minimal error; recommended R1 ≤100kΩ for accuracy. This configuration is explicitly validated for the LTC2911-5 variant.

What is the purpose of the TMR pin on the LTC2911ITS8-5#TRMPBF, and what are its valid configurations?

The TMR pin on the LTC2911ITS8-5#TRMPBF controls reset timeout and latch behavior: floating enables ~400µs minimum timeout; tied to V1 selects internal 200ms timeout; pulled to GND latches RST state indefinitely. This latch mode is critical for margin testing - holding RST low while probing marginal supply voltages without triggering unintended system resets. Propagation delay from TMR release to RST transition is ≤3µs.

Does the LTC2911ITS8-5#TRMPBF support power-fail detection on a 24V supply, and how is it implemented?

Yes - the LTC2911ITS8-5#TRMPBF supports 24V power-fail detection via the PFI pin using an external resistive divider. With a 500mV falling-edge threshold, a 47kΩ/1kΩ divider scales 24V to 0.5V at PFI. The datasheet confirms PFI absolute max rating of 2V and input current ≤±40nA (H-grade), ensuring accuracy. PFO then asserts low to signal imminent failure, enabling controlled shutdown before main rails collapse.