Analog Devices Inc. LTC2903IS6-A1#TRMPBF

Overview

LTC2903IS6-A1#TRMPBF from Analog Devices (formerly Linear Technology) is a precision quad supply monitor IC in a 6-lead TSOT-23 package, designed to supervise 3.3V, 2.5V, 1.8V, and an adjustable input simultaneously. It guarantees ±1.5% threshold accuracy over temperature, features 200ms reset delay, active-low open-drain RST output, and ultralow 20µA quiescent current. It is used in multivoltage systems such as optical networking equipment and network servers where reliable power-up sequencing and brownout detection are critical.

For engineers reviewing the LTC2903IS6-A1#TRMPBF datasheet, LTC2903IS6-A1#TRMPBF pinout, LTC2903IS6-A1#TRMPBF application, or LTC2903IS6-A1#TRMPBF equivalent, key selection considerations include its guaranteed 0.5V VCC operation, four independent voltage thresholds (2.921V/2.213V/1.593V/0.500V), −40°C to 85°C industrial temperature range, SOT-23 footprint compatibility, and absence of internal hysteresis for high-accuracy monitoring.

Technical Context

The LTC2903IS6-A1#TRMPBF implements four independent comparators referenced to a bandgap-derived 0.5V internal reference, with thresholds scaled per input (VRT33, VRT25, VRT18, VRTA). Its reset logic holds RST low until all four inputs exceed their respective thresholds for a guaranteed 200ms period, with glitch immunity achieved via comparator transient filtering and reset timeout counter retriggering.

VCC is autonomously generated from the higher of V1 or V2 (V1 only for D1/E1 variants); for LTC2903IS6-A1#TRMPBF, VCC derives from V1 or V2 depending on relative voltage, enabling operation down to 0.5V. The RST output uses an internal weak pull-up to V2 (10µA typical) and a low-voltage pull-down circuit capable of sinking ≥5µA at VOL ≤ 150mV with VCC = 0.5V.

Key Specifications

Pinout & Package

Package: 6-lead TSOT-23 (ThinSOT™), 1mm height, JEDEC MO-193 compliant, footprint compatible with standard SOT-23 layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC2900CS6-3.3#TRMPBF and LTC2902IS6-3.3#TRMPBF, the LTC2903IS6-A1#TRMPBF uniquely provides one adjustable input for nonstandard rails while maintaining identical accuracy, quiescent current, and industrial temperature rating-making it optimal for mixed-voltage systems with at least one custom-supply requirement.

Availability

LTC2903IS6-A1#TRMPBF is available at Aetrix Electronics and suitable for optical networking systems, network servers, cell phone base stations, and multivoltage industrial controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2903IS6-A1#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 acquired Linear Technology in 2017 and maintains full product support, manufacturing, and documentation for the LTC portfolio.

The LTC2903 series belongs to Linear's precision power supply supervisory IC family, engineered specifically for high-accuracy, low-power, multi-rail monitoring in telecom infrastructure and computing platforms where voltage margin is constrained.

FAQ

What is the guaranteed minimum VCC operating voltage for LTC2903IS6-A1#TRMPBF?

The LTC2903IS6-A1#TRMPBF guarantees full functionality-including RST output assertion and accurate threshold detection-down to VCC = 0.5V. This is validated across the full −40°C to +85°C operating temperature range and enables reliable reset assertion during deep brownout conditions where other supervisors fail.

How does the LTC2903IS6-A1#TRMPBF achieve ±1.5% threshold accuracy without hysteresis?

The LTC2903IS6-A1#TRMPBF achieves ±1.5% accuracy by using a precision bandgap reference and trimmed comparator offsets, avoiding hysteresis that would degrade stated tolerance. Noise immunity is provided instead by proprietary comparator transient filtering-requiring overdrive events to exceed both magnitude and duration thresholds (e.g., >0.1% overdrive for >250µs) before triggering reset.

Can LTC2903IS6-A1#TRMPBF monitor a negative supply like –5.2V?

No. The LTC2903IS6-A1#TRMPBF variant is configured for 3.3V/2.5V/1.8V/ADJ inputs only. For –5.2V monitoring, the LTC2903IS6-C1#TRMPBF variant is required, which specifies V4 input range of –6.5V to 0.3V and a dedicated –5.2V threshold (–4.602V typical). Pinout and package are identical, but internal thresholds differ.

What is the maximum sink current capability of the RST pin on LTC2903IS6-A1#TRMPBF at 0.5V VCC?

At VCC = 0.5V, the RST pin on LTC2903IS6-A1#TRMPBF is guaranteed to sink at least 5µA while maintaining VOL ≤ 150mV. Typical performance exceeds this-measuring ~7µA at VOL = 100mV-enabling robust reset assertion even when driving high-impedance microcontroller reset inputs during low-VCC brownout.

Does LTC2903IS6-A1#TRMPBF require external resistors for the ADJ input?

Yes. The V4 (ADJ) input on LTC2903IS6-A1#TRMPBF compares against an internal 0.5V reference, so an external resistor divider (R1/R2) must be connected between the monitored positive supply and ground, with the divider tap connected to V4. For example, to monitor 1.2V, use R1 = 143kΩ and R2 = 100kΩ (per Linear's Table 1b), yielding VTRIP = 0.5V × (1 + R1/R2) = 1.215V.