Analog Devices Inc. LTC2911HDDB-4#TRMPBF

Overview

LTC2911HDDB-4#TRMPBF from Analog Devices (formerly Linear Technology) is a precision triple supply monitor IC with power-fail comparator, designed for automotive-grade systems operating from –40°C to 125°C. It monitors V1 = 3.3V (±1.5% threshold accuracy), V2 = 1.2V (1.122V nominal reset threshold), and an adjustable ADJ input (500mV threshold), with 30µA typical quiescent current and internal 200ms reset timeout. Used in automotive infotainment power sequencing and industrial PLCs requiring robust undervoltage supervision.

For engineers reviewing the LTC2911HDDB-4#TRMPBF datasheet, LTC2911HDDB-4#TRMPBF pinout, LTC2911HDDB-4#TRMPBF application, or LTC2911HDDB-4#TRMPBF equivalent, key selection criteria include its H-grade temperature range, DFN-8 (3mm × 2mm) package, dual-supply monitoring capability (3.3V/1.2V), PFI-based early power-fail warning, and latch-enabled margin testing support.

Technical Context

The LTC2911HDDB-4#TRMPBF implements three independent voltage comparators: one fixed 3.3V monitor on V1, one fixed 1.2V monitor on V2 (VRT12 = 1.122V), and one adjustable 500mV-threshold comparator on ADJ. All thresholds maintain ±1.5% accuracy over –40°C to 125°C, with built-in glitch filtering for noise immunity.

Its power-fail function uses the PFI input (500mV falling threshold, 515mV rising threshold, 15mV hysteresis) to drive PFO low for early warning; RST asserts low when any monitored supply falls below its threshold and remains low for ≥200ms after recovery. The TMR pin supports internal timeout, external capacitor timing, or latched reset state for margin testing.

Key Specifications

Pinout & Package

Package: 8-lead (3mm × 2mm) plastic DFN (DDB), exposed pad (Pin 9) connected to GND. Thermal resistance θ_JA = 76°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6324HUT46+T and TPS3808G33DBVR, the LTC2911HDDB-4#TRMPBF uniquely delivers simultaneous 3.3V/1.2V/adjustable monitoring with integrated PFI-based early warning and latch-enabled margin testing-critical for complex automotive and industrial systems requiring coordinated multi-rail power integrity assurance.

Availability

LTC2911HDDB-4#TRMPBF is available at Aetrix Electronics and suitable for automotive infotainment, industrial PLCs, and medical imaging equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2911HDDB-4#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. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, acquired Linear Technology in 2017 to strengthen its power management portfolio.

The LTC2911 family was developed by Linear Technology specifically for high-accuracy, low-power multi-rail supply monitoring in automotive, industrial, and computing systems demanding guaranteed operation across extreme temperatures.

FAQ

What is the exact reset threshold voltage for V2 on the LTC2911HDDB-4#TRMPBF?

The V2 reset threshold for LTC2911HDDB-4#TRMPBF is precisely 1.122V (1.2V −6.5%), with guaranteed min/max values of 1.104V and 1.140V over the full –40°C to 125°C operating range. This value is fixed for the "-4" variant and applies to all DFN-packaged versions including LTC2911HDDB-4#TRMPBF.

Does the LTC2911HDDB-4#TRMPBF support external reset timeout configuration?

Yes, the LTC2911HDDB-4#TRMPBF supports both internal and external reset timeout. Tying TMR to V1 enables the fixed 200ms timeout; connecting a capacitor (CTMR) from TMR to GND configures external timeout (e.g., 2.2nF ≈ 20ms). Leaving TMR open yields ~400µs minimum timeout, but leakage must stay below 500nA for accuracy.

How does the power-fail warning (PFO) function differ from the main reset (RST) on the LTC2911HDDB-4#TRMPBF?

The PFO output on LTC2911HDDB-4#TRMPBF asserts low when the PFI input falls below 500mV (early warning), while RST asserts low only when V1, V2, or ADJ falls below their respective thresholds (final reset). PFO typically triggers 10–50ms before RST, enabling preemptive actions like saving state or disabling peripherals before system collapse.

Can the LTC2911HDDB-4#TRMPBF monitor a 5V supply as its third input?

No - the LTC2911HDDB-4#TRMPBF is the "-4" variant, meaning V2 is fixed at 1.2V monitoring. To monitor a 5V supply as the third input, use the ADJ pin with a resistive divider (e.g., 10kΩ + 40kΩ) to scale 5V down to 1.0V, then configure ADJ threshold at 500mV. The PFI pin can also monitor 5V via divider for power-fail warning.

What is the maximum allowable input voltage on the PFI pin of the LTC2911HDDB-4#TRMPBF?

The absolute maximum rating for the PFI pin on LTC2911HDDB-4#TRMPBF is 2.0V. Exceeding this risks permanent damage. For monitoring supplies >2V (e.g., 5V, 12V), a resistive divider must scale the voltage to ≤2V at PFI - e.g., 100kΩ + 25kΩ divider reduces 5V to 1.0V, well within safe operating range.