Analog Devices Inc. LTC2903IS6-D1#TRPBF

Overview

LTC2903IS6-D1#TRPBF from Analog Devices (formerly Linear Technology) is a precision quad supply monitor IC in a 6-lead TSOT-23 package, designed to supervise four voltage rails simultaneously with guaranteed ±1.5% threshold accuracy over temperature. It features three adjustable inputs (V2, V3, V4), a fixed 3.3V (5% tolerance) V1 input, 200ms reset timeout, active-low open-drain RST output, and ultralow 20µA quiescent current - ideal for power-constrained multivoltage systems such as optical networking equipment and telecom base stations.

For engineers reviewing the LTC2903IS6-D1#TRPBF datasheet, LTC2903IS6-D1#TRPBF pinout, LTC2903IS6-D1#TRPBF application, or LTC2903IS6-D1#TRPBF equivalent, key selection considerations include its triple-adjustable monitoring capability, V1-derived internal VCC generation, low-voltage reset operation down to 0.5V, and compatibility with resistor-divider-based trip-point configuration for custom supply thresholds.

Technical Context

The LTC2903IS6-D1#TRPBF implements four independent comparators referenced to an internal 0.5V bandgap, enabling precise undervoltage detection across all four inputs. Its architecture generates internal VCC exclusively from V1 (not V1/V2 selection), supporting operation even when other monitored supplies are absent or unpowered.

Reset assertion requires any input to fall below its threshold; deassertion occurs only after all four inputs exceed their respective thresholds for a guaranteed 140–260ms delay. The RST output uses an internal weak pull-up to V1 (not V2), and its pulldown strength is sourced solely from V1 - a critical distinction from A1/B1/C1 variants that affects external pull-up design and noise immunity.

Key Specifications

Pinout & Package

Package: 6-lead TSOT-23 (ThinSOT™), 1mm profile, JEDEC MO-193 compliant. Pin 1 marked with dot; pin 1 is V1, pin 2 is GND, pin 3 is V2, pin 4 is V3, pin 5 is V4, pin 6 is RST.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC2903IS6-A1#TRPBF, the LTC2903IS6-D1#TRPBF trades fixed 2.5V/1.8V thresholds for full adjustability on three inputs - essential for nonstandard rails - while maintaining identical accuracy, timing, and low-voltage performance. Versus LTC2903IS6-E1#TRPBF, it shifts the fixed V1 threshold from 5V to 3.3V, aligning with modern low-voltage system architectures.

Availability

LTC2903IS6-D1#TRPBF is available at Aetrix Electronics and suitable for optical networking systems, cellular base station power management, and industrial PLC backplane modules requiring stable component supply, long-term lifecycle support, and guaranteed parametric performance across –40°C to +85°C.

Supply support for LTC2903IS6-D1#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 full product support, documentation, and manufacturing continuity for the LTC portfolio.

The LTC2903 series is a precision quad-supply monitoring family designed specifically for high-reliability multivoltage systems where deterministic reset behavior, low-power operation, and accurate threshold tracking across temperature are mandatory.

FAQ

What is the fixed voltage threshold for V1 on the LTC2903IS6-D1#TRPBF?

The LTC2903IS6-D1#TRPBF has a fixed V1 threshold of 3.086V (3.3V nominal with ±1.5% accuracy over temperature). This is specified as a 5% undervoltage monitor - meaning reset asserts when V1 falls below 3.086V and releases only after V1 exceeds 3.086V for 200ms. Unlike A1/B1/C1 variants, V1 is not adjustable and serves as both the primary monitored rail and the sole source of internal VCC.

How do I configure adjustable thresholds on V2, V3, and V4 of the LTC2903IS6-D1#TRPBF?

To configure adjustable thresholds on V2, V3, and V4 of the LTC2903IS6-D1#TRPBF, connect each input to a resistor divider between the target supply voltage and ground, with the divider's tap connected to the respective pin. All three inputs compare against an internal 0.500V reference. Use the formula V_TRIP = 0.5 × (1 + R1/R2) to calculate resistor values. For example, to monitor a 12V rail at 11.25V (–6.5%), use R1 = 2150kΩ and R2 = 100kΩ (1% tolerance).

Does the LTC2903IS6-D1#TRPBF require external bypass capacitors on all voltage inputs?

The LTC2903IS6-D1#TRPBF requires a minimum 0.1µF ceramic bypass capacitor only on V1 (Pin 1), as V1 supplies internal VCC. External capacitors on V2, V3, and V4 are optional and recommended only in electrically noisy environments - unlike A1/B1/C1 variants, which require bypassing on both V1 and V2. This simplifies layout and reduces BOM count for clean power domains.

What is the RST output structure and how should it be interfaced?

The RST output of the LTC2903IS6-D1#TRPBF is an active-low open-drain pin with an internal weak pull-up to V1 (not V2). It sinks ≥5µA at VOL ≤150mV when VCC = 0.5V. For logic-high levels exceeding V1 or faster rise times, an external pull-up resistor is required. The pin supports wired-OR configurations and is compatible with 1.8V–5V logic families when properly terminated.

Can the LTC2903IS6-D1#TRPBF monitor negative voltages like –5.2V?

No, the LTC2903IS6-D1#TRPBF cannot directly monitor negative voltages. Its V2, V3, and V4 inputs are specified for 0.55V to 6.5V (absolute max –0.3V), and the internal 0.5V reference is positive-only. To supervise –5.2V (as supported by the C1 variant), a level-shifting circuit or external inverting amplifier is required - making the LTC2903IS6-C1#TRPBF the appropriate choice for true negative-rail monitoring.