Analog Devices Inc. LTC1727EMS8-2.5#PBF

Overview

LTC1727EMS8-2.5#PBF from Analog Devices is a micropower precision triple supply monitor IC in 8-lead MSOP package, designed to simultaneously monitor 2.5V, 3.3V, and an adjustable supply (VCCA) with ±1.5% threshold accuracy over temperature. It provides three individual open-drain comparator outputs (COMP25, COMP3, COMPA) plus a common active-low reset output (RST) with 200ms delay, ensuring reliable power-up sequencing in multi-rail systems such as notebook computers and intelligent instruments.

For engineers reviewing the LTC1727EMS8-2.5#PBF datasheet, LTC1727EMS8-2.5#PBF pinout, LTC1727EMS8-2.5#PBF application, or LTC1727EMS8-2.5#PBF equivalent, key selection criteria include its guaranteed RST assertion down to VCC3 or VCC25 ≥1V, 10µA typical supply current, glitch-immune monitoring architecture, and support for flexible supply configurations (e.g., dual-supply or single-supply monitoring via VCCA tie-off).

Technical Context

The LTC1727EMS8-2.5#PBF implements three independent voltage comparators feeding into a 200ms reset timer and logic OR gate, with internal bandgap reference enabling operation across –40°C to +85°C. Its power-detect architecture autonomously selects VCC3 or VCC25 as the supply rail based on which voltage is higher, ensuring RST remains valid even during brownout transitions.

Each comparator output (COMP25, COMP3, COMPA) is open-drain with weak internal 6µA pull-up to VCC3 and supports external pull-up to voltages exceeding VCC3. The RST output is guaranteed functional at VCC3 ≥1V or VCC25 ≥1V, while COMPA requires VCC3 or VCC25 ≥2V to assert correctly due to bandgap reference startup constraints.

Key Specifications

Pinout & Package

Package: 8-Lead Plastic MSOP (MS8), 3.00mm × 3.00mm body, 0.65mm pitch, lead-free finish, –40°C to +85°C operating range.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC1326-2.5 and LTC1726-2.5, the LTC1727EMS8-2.5#PBF offers superior power efficiency (10µA vs. 25–35µA) and autonomous supply selection, making it optimal for battery-critical designs where fixed accuracy is acceptable and dynamic rail prioritization is required.

Availability

LTC1727EMS8-2.5#PBF is available at Aetrix Electronics and suitable for notebook computers, intelligent instruments, desktop computers, portable battery-powered equipment, and network servers requiring stable component supply and long-term lifecycle support.

Supply support for LTC1727EMS8-2.5#PBF 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC1727 product line delivers micropower precision supply monitoring for multi-rail systems, targeting applications demanding ultra-low quiescent current, tight threshold accuracy, and robust glitch immunity in space-constrained environments.

FAQ

What is the function of the VCCA pin on the LTC1727EMS8-2.5#PBF?

The VCCA pin on the LTC1727EMS8-2.5#PBF is a high-impedance input that monitors an adjustable supply rail with a fixed 1.000V threshold. It supports direct connection to DC/DC converter feedback dividers or custom voltage nodes. If unused, VCCA may be tied to VCC3 or VCC25 without affecting threshold accuracy, as both are guaranteed above 1.015V.

How does the LTC1727EMS8-2.5#PBF ensure reliable reset during power-up?

The LTC1727EMS8-2.5#PBF ensures reliable reset during power-up by asserting RST low until all three monitored supplies (VCC25, VCC3, VCCA) exceed their respective thresholds for a continuous 200ms period. Its power-detect architecture automatically selects VCC3 or VCC25 as the supply source, guaranteeing RST validity even when either rail reaches only 1V.

Can the LTC1727EMS8-2.5#PBF monitor only two supplies instead of three?

Yes, the LTC1727EMS8-2.5#PBF can monitor one or two supplies. Unused inputs like VCCA may be tied to VCC3 or VCC25, and the device will still generate a valid RST output based on the active monitored rails. This flexibility allows reuse across designs with varying rail counts without hardware changes.

What is the maximum supply voltage the LTC1727EMS8-2.5#PBF can tolerate on its input pins?

The LTC1727EMS8-2.5#PBF has an absolute maximum rating of –0.3V to 7V on VCC25, VCC3, VCCA, RST, and comparator output pins. Operation beyond 7V risks permanent damage. For reliable functionality, VCC25 and VCC3 should remain within 2.5V ±10% and 3.3V ±10%, respectively, to maintain ±1.5% threshold accuracy.

Does the LTC1727EMS8-2.5#PBF provide individual supply status outputs?

Yes, the LTC1727EMS8-2.5#PBF provides three individual open-drain comparator outputs: COMP25 (for VCC25), COMP3 (for VCC3), and COMPA (for VCCA). Each asserts high when its respective supply exceeds its threshold and supports external pull-up resistors for level-shifting, enabling per-rail diagnostics and fault isolation in complex systems.