Analog Devices Inc. ADM13305-25ARZ-RL7

Overview

ADM13305-25ARZ-RL7 from Analog Devices is a dual-voltage supervisor IC designed to monitor 3.3 V and 2.5 V power rails in microprocessor/DSP systems, providing both active-high and active-low reset outputs with 140 ms minimum timeout, 1.6 sec watchdog timer, and operation from 2.7 V to 5.5 V supply. It supports industrial temperature range (−40°C to +85°C) and is used in notebook computers and wireless baseband modules.

For engineers reviewing the ADM13305-25ARZ-RL7 datasheet, ADM13305-25ARZ-RL7 pinout, ADM13305-25ARZ-RL7 application, or ADM13305-25ARZ-RL7 equivalent, key selection considerations include fixed 2.93 V / 2.25 V undervoltage thresholds, push-pull RESET/RESET outputs, watchdog enable/disable via WDI pin, and SOIC_N-8 package compatibility with board-level noise immunity requirements.

Technical Context

The ADM13305-25ARZ-RL7 integrates two independent voltage comparators with hysteresis (20 mV at 2.25 V threshold), a precision oscillator for watchdog timing, and logic-controlled reset assertion/deassertion based on SENSE1/SENSE2 input transitions relative to pretrimmed VIT+ and VIT− levels. Its internal reference ensures stable threshold tracking across temperature.

It implements dual-reset architecture: RESET asserts low when either monitored supply falls below its falling threshold (VIT−), while RESET asserts high under identical conditions; both outputs remain valid down to VDD = 1.1 V and feature push-pull drivers capable of ±3 mA sink/source at 5.5 V.

Key Specifications

Pinout & Package

ADM13305-25ARZ-RL7 is housed in an 8-lead narrow-body SOIC (SOIC_N, package code R-8), JEDEC MS-012-AA compliant, with 1.27 mm lead pitch and 5.00 mm × 4.00 mm body dimensions.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-supply supervision applications.

Compared with MAX6816ESE+ and TPS3808G33DBVR, the ADM13305-25ARZ-RL7 uniquely delivers simultaneous 3.3 V/2.5 V supervision, native dual-polarity reset outputs, and integrated watchdog - making it the only option that avoids redesigning power sequencing logic or adding discrete components in new dual-rail embedded systems.

Availability

ADM13305-25ARZ-RL7 is available at Aetrix Electronics and suitable for notebook computers, wireless gateways, industrial PLCs, and baseband processor platforms requiring stable component supply across extended temperature and long production lifecycles.

Supply support for ADM13305-25ARZ-RL7 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, communications, automotive, and consumer markets since 1965.

The ADM13305 product line delivers precision dual-supervisory functions for microprocessor-based systems, targeting applications where reliability, low power, and dual-rail coordination are critical - such as portable computing and wireless infrastructure.

FAQ

What is the exact undervoltage threshold for SENSE2 on the ADM13305-25ARZ-RL7?

The ADM13305-25ARZ-RL7 has a factory-trimmed SENSE2 falling threshold (VIT−) of 2.20 V to 2.32 V over −40°C to +85°C, with a typical value of 2.25 V. This is optimized for monitoring 2.5 V supplies and includes 20 mV hysteresis to reject noise-induced false resets. The threshold is fixed and does not require external resistors.

Can the ADM13305-25ARZ-RL7 supervise a 1.8 V rail?

No - the ADM13305-25ARZ-RL7 is specifically configured for 3.3 V (SENSE1) and 2.5 V (SENSE2) rails. For 1.8 V supervision, use the pin-compatible ADM13305-18ARZ-RL7 variant, which features 2.93 V / 1.68 V thresholds. The -25 version's SENSE2 input is trimmed to 2.25 V and cannot accurately detect 1.8 V undervoltage conditions.

Does the ADM13305-25ARZ-RL7 require external components to operate?

The ADM13305-25ARZ-RL7 operates autonomously with only a 0.1 μF VDD-to-GND bypass capacitor recommended for noise immunity. No external resistors, capacitors, or pull-ups are needed for basic supervision, reset timing, or watchdog functionality - all thresholds, timeouts, and output drive strengths are internally fixed and specified across temperature.

How does the watchdog timer in the ADM13305-25ARZ-RL7 interact with the manual reset (MR) pin?

In the ADM13305-25ARZ-RL7, the MR pin and watchdog timer operate independently but share the same RESET/RESET outputs. Asserting MR low forces immediate reset regardless of watchdog state; releasing MR initiates the 140 ms timeout before deassertion. The watchdog continues monitoring WDI during MR assertion and will trigger if WDI is not toggled - ensuring fail-safe behavior even during manual intervention.

Is the ADM13305-25ARZ-RL7 RoHS compliant and what is its packaging format?

Yes, the ADM13305-25ARZ-RL7 is RoHS compliant (indicated by the "Z" suffix) and supplied in tape-and-reel format (RL7 designation). It uses an 8-lead narrow-body SOIC package (R-8, JEDEC MS-012-AA), with dimensions 5.00 mm × 4.00 mm × 1.75 mm and 1.27 mm lead pitch - compatible with standard SOIC pick-and-place equipment and reflow profiles.