Diodes Incorporated PT7M7825STAEX

Overview

PT7M7825STAEX from Diodes Incorporated is a precision microprocessor supervisory IC with push-pull active-low RESET output, manual reset (MR) input, and watchdog timer (WDI) functionality. It monitors VCC for power-up, brownout, and power-down conditions with a 2.25V reset threshold (VRST), delivers a guaranteed 200ms reset pulse width (tRS), and operates down to VCC = 1.0V-enabling reliable system initialization in embedded microcontroller applications such as industrial controllers and network edge devices.

For engineers reviewing the PT7M7825STAEX datasheet, PT7M7825STAEX pinout, PT7M7825STAEX application, or PT7M7825STAEX equivalent, key selection criteria include its 2.25V threshold accuracy (±2.5% over –40°C to +85°C), integrated MR debouncing, WDI edge-triggered watchdog timeout of 1.6s (typ), push-pull RESET drive capability up to 800µA sink at 5.5V, and SOT23-5 package compatibility with space-constrained PCB layouts.

Technical Context

The PT7M7825STAEX implements a dual-function supervisory architecture: a precision voltage monitor with hysteresis (VRTH = 4mV for T/S/R/K/Z/Y variants) and a retriggerable watchdog timer that clears on any WDI rising or falling edge. Its internal timebase ensures deterministic reset assertion during VCC transitions and guarantees RESET validity even when VCC drops to 1.0V.

It integrates an internal MR pull-up resistor (52 kΩ typ) and supports CMOS-compatible logic levels for MR and WDI inputs (VIH ≥ 0.7VCC, VIL ≤ 0.3VCC). The push-pull RESET output drives low to ≤0.3V at 1.0V VCC with 100µA sink current, enabling direct interfacing with µP reset pins without external pull-ups.

Key Specifications

Pinout & Package

PT7M7825STAEX is housed in a 5-pin SOT23-5 (TA) plastic package with gull-wing leads, optimized for automated assembly and thermal performance in high-density layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with APX823T-22SA-7 and MAX6326XR23D3+T, PT7M7825STAEX uniquely combines 2.25V precision monitoring, integrated WDI and MR, and push-pull RESET in a single SOT23-5 package-reducing component count and enabling full supervisory coverage where space and feature density are constrained.

Availability

PT7M7825STAEX is available at Aetrix Electronics and suitable for industrial automation, network infrastructure, embedded security, and server management applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for PT7M7825STAEX 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and communications markets.

The PT7M78xx family was designed specifically to replace discrete reset circuits in µP-based systems-integrating voltage monitoring, manual reset, and watchdog functions into a single low-quiescent-current IC for space- and cost-sensitive embedded designs.

FAQ

What is the minimum VCC voltage at which PT7M7825STAEX guarantees valid RESET assertion?

PT7M7825STAEX guarantees RESET remains a valid logic low (≤0.3V) down to VCC = 1.0V, as confirmed in the DC Electrical Characteristics table. This ensures fail-safe reset behavior during severe brownout or battery-depletion scenarios where supply voltage collapses below nominal thresholds but remains above silicon operational limits.

Does PT7M7825STAEX require an external pull-up resistor on the RESET pin?

No. PT7M7825STAEX features a push-pull RESET output, meaning it actively drives both high and low states without requiring an external pull-up resistor. This reduces BOM count and eliminates potential timing skew introduced by RC time constants in open-drain configurations.

How does the watchdog timer respond to WDI signal transitions?

The watchdog timer clears on any detected rising or falling edge at the WDI pin. Pulses as short as 150ns are reliably captured. If WDI remains static (high or low) for longer than the 1.6s typical timeout period, the device asserts RESET-providing robust firmware hang detection independent of clock source stability.

Can the manual reset (MR) input be left unconnected in a design?

Yes. PT7M7825STAEX includes an internal MR pull-up resistor (52 kΩ typical), so the MR pin may be left floating or tied directly to VCC when manual reset functionality is not required. No external components are needed to disable MR, simplifying layout and reducing risk of accidental reset assertion.