Analog Devices Inc. LTC2953CDD-2#TRPBF

Overview

LTC2953CDD-2#TRPBF from Analog Devices (formerly Linear Technology) is a push-button on/off controller with high-voltage open-drain enable output (⎯E⎯N), input/output supply monitoring, and microprocessor handshake capability. It operates from 2.7V to 27V, draws only 14μA quiescent current, features ±1.5% threshold accuracy, and supports 200ms reset timing via VM pin. It is used in battery-powered instrumentation and blade servers for orderly power sequencing.

For engineers reviewing the LTC2953CDD-2#TRPBF datasheet, LTC2953CDD-2#TRPBF pinout, LTC2953CDD-2#TRPBF application, or LTC2953CDD-2#TRPBF equivalent, key selection criteria include its high-voltage ⎯E⎯N output for PFET control, adjustable power-down timer (tPDT), UVLO lockout behavior, and 12-pin 3mm × 3mm DFN package with exposed pad.

Technical Context

The LTC2953CDD-2#TRPBF implements dual-function supply monitoring: an uncommitted power-fail comparator (PFI → ⎯P⎯F⎯O) and a latched under-voltage lockout (UVLO → ⎯I⎯N⎯T + EN release). Both comparators reference a precise 0.5V internal bandgap and operate independently of push-button state.

Its control logic includes a 32ms push-button debounce (tDB,ON/tDB,OFF), 512ms ⎯K⎯I⎯L⎯L turn-on blanking window, fixed 64ms internal power-down delay (tPD,Min), and capacitor-adjustable additional delay (tPDT = 6.4s/μF at PDT pin). The ⎯E⎯N output is active-low and rated to 50V, enabling direct control of external high-side PFETs.

Key Specifications

Pinout & Package

Package: 12-lead 3mm × 3mm plastic DFN (DD) with exposed thermal pad (Pin 13), RoHS-compliant, tape-and-reel (TRPBF).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar push-button power control applications.

Compared with TPS3808G33DBVR and MAX16054ATA+, the LTC2953CDD-2#TRPBF uniquely integrates push-button interface, high-voltage ⎯E⎯N output for PFET control, dual-supply monitoring (PFI + UVLO), and configurable power-down timing-making it the only option that fully implements a self-contained, μP-handshaked power-on/off controller in a single 3mm × 3mm package.

Availability

LTC2953CDD-2#TRPBF is available at Aetrix Electronics and suitable for battery-powered instrumentation, blade server power management, and industrial PLC I/O modules requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for LTC2953CDD-2#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, formed through the acquisition of Linear Technology in 2017.

The LTC2953 product line was designed specifically for intelligent, push-button-initiated power sequencing in space-constrained, battery-sensitive, and high-reliability systems-emphasizing low quiescent current, accurate voltage thresholds, and robust μP handshaking.

FAQ

What is the function of the ⎯E⎯N pin on the LTC2953CDD-2#TRPBF?

The ⎯E⎯N pin on the LTC2953CDD-2#TRPBF is an active-low, high-voltage (50V max) open-drain enable output. It directly controls the gate of an external high-side PFET to switch system power on/off. Unlike the LTC2953-1's EN (active-high), the LTC2953CDD-2#TRPBF's ⎯E⎯N asserts low to turn on power and releases high to shut down-enabling efficient power path design without level shifters.

How does the LTC2953CDD-2#TRPBF handle undervoltage conditions during startup?

The LTC2953CDD-2#TRPBF prevents system power-on when the UVLO pin voltage falls below 0.5V (±1.5%) by locking out the ⎯P⎯B input. This UVLO lockout ensures the device will not assert ⎯E⎯N unless the input supply is sufficiently stable-avoiding erratic behavior or brown-out operation during cold start or weak battery conditions.

Can the LTC2953CDD-2#TRPBF be used without a microprocessor?

Yes-the LTC2953CDD-2#TRPBF supports autonomous operation: push-button presses directly toggle ⎯E⎯N and generate debounced ⎯I⎯N⎯T pulses. However, full functionality-including safe power-down coordination and aborted-startup detection-requires connecting ⎯K⎯I⎯L⎯L to a μP or logic circuit that drives it high within 512ms of power-on and low to initiate shutdown.

What is the purpose of the PDT pin on the LTC2953CDD-2#TRPBF?

The PDT pin on the LTC2953CDD-2#TRPBF sets an adjustable delay (tPDT) before the ⎯E⎯N output is released during forced power-down. By connecting an external capacitor (e.g., 1500pF yields ~11.5ms), users extend the default 64ms internal delay, ensuring sufficient time for μP housekeeping before power removal-even if the processor fails to respond to the ⎯I⎯N⎯T interrupt.

Does the LTC2953CDD-2#TRPBF provide independent reset and power-fail monitoring?

Yes-the LTC2953CDD-2#TRPBF provides three independent monitoring functions: VM pin drives ⎯R⎯S⎯T with 200ms reset timing; PFI pin drives ⎯P⎯F⎯O for real-time power-fail warning; and UVLO pin drives ⎯I⎯N⎯T + ⎯E⎯N release for controlled shutdown. Each uses the same 0.5V reference but operates with separate comparators, hysteresis, and timing-ensuring no functional coupling between reset, warning, and shutdown paths.