Analog Devices Inc. LTC1726ES8-2.5#TRPBF

Overview

LTC1726ES8-2.5#TRPBF from Analog Devices (formerly Linear Technology) is a triple supply monitor and microprocessor supervisory IC with adjustable reset and watchdog timer functions, designed for systems requiring simultaneous monitoring of 2.5V, 3.3V, and an adjustable voltage rail. It features ±1.5% threshold accuracy over temperature, 16µA typical supply current, and guaranteed RST assertion down to VCC3 ≥ 1V or VCC25 ≥ 1V - ideal for power-critical embedded instrumentation and portable computing.

For engineers reviewing the LTC1726ES8-2.5#TRPBF datasheet, LTC1726ES8-2.5#TRPBF pinout, LTC1726ES8-2.5#TRPBF application, or LTC1726ES8-2.5#TRPBF equivalent, key selection criteria include its dual-supply monitoring flexibility (2.5V/3.3V/ADJ), capacitor-adjustable reset/watchdog timeouts, open-drain active-low RST output, and guaranteed operation across –40°C to +85°C in SO-8 package.

Technical Context

The LTC1726ES8-2.5#TRPBF integrates three independent voltage comparators (for VCC25 = 2.5V, VCC3 = 3.3V, and VCCA ≈ 1V), a programmable reset timer (tRT = 3.30 × CRT), and a watchdog timer (tWT = 21.8 × CWT), all sharing a common open-drain RST output. Its internal power-detect logic autonomously selects VCC25 or VCC3 as the supply source based on relative voltage level.

Glitch immunity is ensured by tight 1.5% threshold tolerance and fast undervoltage detection (130µs response). The device supports configuration for two-input or single-input monitoring via pin strapping, and disables unused inputs without compromising accuracy - critical for reliable brownout recovery in battery-powered systems.

Key Specifications

Pinout & Package

Package: 8-Lead Plastic SO (Small Outline, Narrow 0.150", S8), RoHS-compliant, tape-and-reel (TRPBF).

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 LTC1727-2.5, the LTC1726ES8-2.5#TRPBF offers the optimal balance of adjustable timing, moderate accuracy, and minimal footprint - making it preferred for cost-sensitive, space-constrained designs where a single reset signal suffices.

Availability

LTC1726ES8-2.5#TRPBF is available at Aetrix Electronics and suitable for desktop computers, notebook computers, and intelligent instruments requiring stable component supply with guaranteed –40°C to +85°C operation and RoHS compliance.

Supply support for LTC1726ES8-2.5#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 legacy Linear parts including the LTC1726 family.

The LTC1726 series was designed as a micropower, high-accuracy triple-supply supervisor targeting portable and embedded systems where reliable power sequencing and watchdog supervision are critical.

FAQ

What is the function of the VCCA pin on the LTC1726ES8-2.5#TRPBF?

The VCCA pin on the LTC1726ES8-2.5#TRPBF is a high-impedance input with a nominal 1.000V threshold (±1.5%), used to monitor an adjustable voltage rail - such as 1.8V derived via resistor divider. If unused, it may be tied to VCC3 or VCC25; it is never used as a power source. This enables flexible third-rail monitoring without external components.

How do I configure the LTC1726ES8-2.5#TRPBF to monitor only two supplies?

The LTC1726ES8-2.25#TRPBF can be configured for dual-supply monitoring by tying the unused VCCA pin to VCC3 or VCC25, effectively disabling its comparator. For example, connecting VCCA to VCC3 configures the device to supervise only VCC25 and VCC3 - verified in the Applications Information section of the datasheet.

What capacitor values set typical 155ms reset and 1s watchdog timeouts for the LTC1726ES8-2.5#TRPBF?

For the LTC1726ES8-2.5#TRPBF, a 47nF capacitor on RT yields tRT = 3.30 × 47,000 = 155,100 µs (155ms); a 47nF capacitor on WT yields tWT = 21.8 × 47,000 = 1,024,600 µs (~1.02s). Ceramic capacitors are recommended for low leakage and stability across temperature.

Does the LTC1726ES8-2.5#TRPBF support operation when only one supply is present?

Yes - the LTC1726ES8-2.5#TRPBF operates with power derived solely from VCC25 or VCC3 (whichever is higher), and guarantees RST assertion as long as either reaches ≥1V. VCCA is not used for power. This enables robust startup even when only the 2.5V or 3.3V rail is active initially.

Is the LTC1726ES8-2.5#TRPBF pin-compatible with other variants like LTC1726ES8-5#TRPBF?

Yes - the LTC1726ES8-2.5#TRPBF is pin-compatible with all SO-8 variants (e.g., LTC1726ES8-5#TRPBF, LTC1726IS8-2.5#TRPBF) in the same package. Thresholds differ by variant (2.5V vs 5V monitoring), but pin functions, timing behavior, and electrical interface remain identical - allowing drop-in replacement with schematic updates only to supply connections.