Analog Devices Inc. LTC2956IUD-1#TRPBF

Overview

LTC2956IUD-1#TRPBF from Analog Devices (formerly Linear Technology) is a micropower, wide-input wake-up timer IC with pushbutton control and active-high enable output. It operates from 1.5V to 36V, delivers 0.8µA quiescent current in awake state and 0.3µA in shutdown, and supports configurable wake-up periods from 250ms to 39 days-enabling periodic sensor monitoring or image capture in battery-powered remote telemetry systems.

For engineers reviewing the LTC2956IUD-1#TRPBF datasheet, LTC2956IUD-1#TRPBF pinout, LTC2956IUD-1#TRPBF application, or LTC2956IUD-1#TRPBF equivalent, this device serves as a low-power system power sequencer for portable instrumentation, intervalometers, and data acquisition nodes requiring precise sleep/awake timing and robust pushbutton interface with ±25kV HBM ESD protection.

Technical Context

The LTC2956IUD-1#TRPBF implements a dual-stage timing architecture: a digitally controlled wake-up period counter (adjustable via PERIOD/RANGE resistors) and an analog-digital hybrid maximum awake timer (set by ONMAX capacitor). Its internal 3.3V regulator powers the PB pull-up and logic, while biasing of configuration pins occurs only during periodic 66-second configuration cycles to minimize leakage.

It features three open-drain status outputs (ONALERT, OFFALERT, PBOUT), debounced pushbutton input with 32ms typical debounce time, and a dedicated SLEEP input that allows external microcontroller-driven early wake-up or forced shutdown via long pulse detection-enabling both passive (capacitor-timed) and active (MCU-synchronized) power management modes.

Key Specifications

Pinout & Package

12-lead 3mm × 3mm QFN package (UD), exposed pad (Pin 13) connected to GND. Pinout validated per Linear Technology LTC2956 datasheet Rev. FA (2017).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar wake-up timer applications.

Compared with TPL5010IPW and MAX16054ETA+, the LTC2956IUD-1#TRPBF uniquely combines ultra-wide supply range, hardware-configurable wake/awake timing, triple alert outputs, and robust pushbutton interface-making it the only option supporting both passive (capacitor-timed) and active (MCU-controlled) power management in harsh industrial environments.

Availability

LTC2956IUD-1#TRPBF is available at Aetrix Electronics and suitable for remote environmental sensing, portable medical logging, industrial intervalometry, asset tracking beacons, and battery-backed data acquisition requiring stable component supply across extended temperature ranges and multi-year field deployment.

Supply support for LTC2956IUD-1#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 acquired Linear Technology in 2017 and maintains its precision analog and power management product lines with full datasheet, simulation model, and application support.

The LTC2956 series was designed specifically for ultra-low-power, wide-input industrial and portable systems requiring reliable hardware-based wake-up sequencing without MCU intervention-targeting applications where firmware reliability and battery longevity are critical.

FAQ

What is the key functional difference between LTC2956IUD-1#TRPBF and LTC2956IUD-2#TRPBF?

The LTC2956IUD-1#TRPBF features an active-high EN output optimized for direct connection to the RUN/SHDN pin of DC/DC converters like the LT3060, while the LTC2956IUD-2#TRPBF provides an active-low EN output capable of directly driving the gate of a P-channel MOSFET. Both share identical timing, configuration, and status functionality-but differ solely in EN polarity and internal pull-up structure. The LTC2956IUD-1#TRPBF is selected when interfacing with standard enable-active-high regulators.

How does the ONMAX capacitor affect system behavior in the LTC2956IUD-1#TRPBF?

The ONMAX capacitor on the LTC2956IUD-1#TRPBF sets the maximum allowed awake time (tONMAX) at 13.3ms per nanofarad, providing hardware-enforced termination of the awake state even if the connected MCU fails to assert SLEEP. If left floating, tONMAX defaults to 8ms; if tied to GND, the minimum awake time applies. This feature prevents excessive battery drain during firmware lockups and is critical for unattended deployments where software reliability cannot be guaranteed.

Can the LTC2956IUD-1#TRPBF operate from a single-cell Li-ion battery?

Yes, the LTC2956IUD-1#TRPBF supports input voltages from 1.5V to 36V, fully covering the 3.0V–4.2V operating range of a single-cell Li-ion battery throughout its discharge cycle. Its 1.24V undervoltage lockout (with 100mV hysteresis) ensures clean startup above 1.08V and prevents erratic operation near end-of-life. Quiescent current remains at 0.8µA awake and drops to 0.3µA in shutdown-maximizing usable capacity in portable designs.

What is the purpose of the LONG pin on the LTC2956IUD-1#TRPBF?

The LONG pin on the LTC2956IUD-1#TRPBF configures the duration threshold (tLONG = 128ms–16.4s) required to enter SHUTDOWN mode via long pushbutton press or sustained SLEEP high signal. It uses a resistor divider with an internal 100kΩ reference to set VLONG relative to VIN; if VLONG > VIN/2, the device powers up in RUN mode, otherwise in SHUTDOWN. This enables shipping-ready "off-by-default" configurations and field-resettable power policies without firmware involvement.

Does the LTC2956IUD-1#TRPBF require external components to function as a basic wake-up timer?

Yes, minimal external components are required: a resistor from PERIOD to GND sets the base wake-up interval (e.g., 100kΩ = 250ms), a second resistor from RANGE to GND selects the decade multiplier (e.g., 17.4kΩ = ×4), and a capacitor from ONMAX to GND defines maximum awake time (e.g., 3.9nF = 52ms). The PB pull-up is internal, and EN drives most regulators directly-so total BOM adds only three passive components for full hardware-configured operation.