Analog Devices Inc. LTC2901-2IGN#TRPBF

Overview

LTC2901-2IGN#TRPBF from Analog Devices (acquired Linear Technology) is a programmable quad supply monitor IC with push-pull RST output, simultaneously supervising four independent voltage rails (e.g., 5V, 3.3V, 2.5V, 1.8V), ±1.5% threshold accuracy over temperature, 43μA typical supply current, and adjustable reset/watchdog timing via external capacitors. It is used in multivoltage embedded systems requiring reliable power-on reset and microprocessor watchdog supervision.

For engineers reviewing the LTC2901-2IGN#TRPBF datasheet, LTC2901-2IGN#TRPBF pinout, LTC2901-2IGN#TRPBF application, or LTC2901-2IGN#TRPBF equivalent, key selection criteria include its push-pull RST output (vs open-drain variants), 16-lead narrow SSOP package, 1V minimum VCC operation, guaranteed glitch immunity, and support for both positive and negative adjustable thresholds via external resistor dividers.

Technical Context

The LTC2901-2IGN#TRPBF implements four independent high-accuracy comparators with user-selectable thresholds across 16 combinations of preset (5V/3.3V/3V/2.5V/1.8V/1.5V) and ±adjustable modes, programmed via a resistive divider on VPG referenced to VREF (1.210V). Its internal bandgap reference ensures ±1.5% threshold tolerance over –40°C to 85°C.

Reset assertion is synchronized to all monitored supplies; RST remains low until all inputs exceed their thresholds, then holds low for a capacitor-programmable delay (tRST = 4.6 ms/nF). The watchdog timer (tWD = 20 ms/nF) clears on WDI edge transitions and asserts RST directly (no separate WDO pin) in LTC2901-2/LTC2901-4 variants, eliminating need for external OR-ing logic.

Key Specifications

Pinout & Package

Package: 16-lead narrow plastic SSOP (GN16), 0.15mm max height, 0.65mm pitch, RoHS-compliant lead-free (#PBF).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC2901-2IGN#PBF, the #TRPBF variant offers optimized logistics for high-volume SMT placement, while TPS3307-33DGNR trades quad monitoring and adjustability for lower cost and simpler configuration in triple-rail systems.

Availability

LTC2901-2IGN#TRPBF is available at Aetrix Electronics and suitable for desktop computers, telecom equipment, network servers, and portable battery-powered equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LTC2901-2IGN#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 semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies.

The LTC2901 product line was originally developed by Linear Technology (acquired by ADI in 2017) to address demand for highly accurate, flexible, and low-power supply monitoring in complex multivoltage systems - particularly in computing, communications, and industrial infrastructure.

FAQ

What is the function of the VPG pin on the LTC2901-2IGN#TRPBF?

The VPG pin on the LTC2901-2IGN#TRPBF is the voltage threshold programming input. It accepts a resistive divider tap between VREF (1.210V) and GND to select one of 16 predefined combinations of voltage thresholds for V1–V4. This enables flexible configuration for mixed-rail systems without changing the IC. The LTC2901-2IGN#TRPBF samples VPG during a ~150μs window after VCC rises above 2.4V, locking in the selected mode.

Does the LTC2901-2IGN#TRPBF support monitoring negative supply voltages?

Yes, the LTC2901-2IGN#TRPBF supports negative rail monitoring via its –ADJ mode on the V4 input. In this mode, an external resistor divider connects between the negative supply and VREF (1.210V), with V4 tied to the divider's tap. The internal comparator references VREF to shift the trip point, enabling accurate detection of undervoltage on rails such as –5V or –12V. The LTC2901-2IGN#TRPBF datasheet specifies VRTAN = ±18mV for –ADJ threshold accuracy.

How does the watchdog timer operate in the LTC2901-2IGN#TRPBF compared to the LTC2901-1?

In the LTC2901-2IGN#TRPBF, the watchdog timer does not drive a dedicated WDO pin. Instead, a missed WDI edge triggers a full RST pulse for the programmed tRST duration - merging watchdog fault response with system reset. This differs from the LTC2901-1, which asserts WDO low independently. The LTC2901-2IGN#TRPBF simplifies system design by eliminating need for external logic to combine WDO with RST, making it ideal for space-constrained applications.

What is the minimum supply voltage required for valid operation of the LTC2901-2IGN#TRPBF?

The LTC2901-2IGN#TRPBF guarantees correct RST and COMPX logic states for VCC ≥ 1V, where VCC is defined as the greater of V1 or V2. This ensures reliable reset assertion during deep brownout conditions. Programming requires VCC ≥ 2.42V (min), and comparator operation begins at VCC ≥ 2.32V (min). Below 1V, outputs are not specified, but the part remains latchable and resumes normal operation once VCC exceeds 1V.

Can the LTC2901-2IGN#TRPBF monitor fewer than four voltage rails?

Yes, the LTC2901-2IGN#TRPBF can monitor fewer than four rails. Unused inputs (e.g., V3 or V4) may be tied to a valid voltage within the –0.3V to 7V absolute maximum rating, or left floating only if configured in ADJ/–ADJ mode with appropriate external dividers. For example, tying V3 to V2 configures the device as a triple-supply monitor. All four comparators remain active, but only asserted outputs affect RST; unused COMPx pins can be ignored or monitored separately for diagnostics.