Diodes Incorporated PT7M7825LTAEX

Overview

PT7M7825LTAEX from Diodes Incorporated is a precision microprocessor (μP) supervisory circuit with 4.63V reset threshold, push-pull RESET output, manual-reset input (MR), and watchdog timer (WDI) functionality. It asserts a guaranteed 200ms active-low reset pulse during power-up, brownout, or manual trigger events, and operates down to VCC = 1.0V - enabling reliable system initialization in embedded power-supply monitoring applications.

For engineers reviewing the PT7M7825LTAEX datasheet, PT7M7825LTAEX pinout, PT7M7825LTAEX application, or PT7M7825LTAEX equivalent, key selection criteria include its 4.63V precision voltage monitor, integrated watchdog timeout (~1.6s), debounced CMOS-compatible MR input, push-pull RESET drive capability, and SOT23-5 package compatibility for space-constrained μP systems.

Technical Context

The PT7M7825LTAEX implements a dual-function reset generator with independent timing control: a 200ms reset timeout (tRS) triggered by VCC crossing VRST (4.63V ±2.5%), MR deassertion, or WDI timeout, and a 1.6s watchdog timeout (tWD) that resets the system if WDI remains static beyond that window. Its internal timebase ensures deterministic behavior across -40°C to +85°C.

It features a dedicated push-pull RESET output capable of sinking 3.2mA at VCC ≥4.5V (VOL ≤0.4V), an internally pulled-up MR input (52kΩ typical), and WDI edge-sensitive detection (150ns minimum pulse width). The device guarantees RESET validity down to VCC = 1.0V, supporting low-voltage brownout detection before full rail stabilization.

Key Specifications

Pinout & Package

PT7M7825LTAEX is housed in a 5-pin SOT23-5 (TA) plastic surface-mount package, optimized for compact PCB layouts and automated assembly. Pin assignments are validated per Diodes Document 43008 Rev 2-4.

Key Features

Applications

Equivalent & Alternatives

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

Compared with APX823T-33SA-7 and TPS3808G33DBVR, PT7M7825LTAEX uniquely combines 4.63V precision monitoring, integrated watchdog, debounced MR, and push-pull RESET in a single SOT23-5 package - making it optimal for compact, self-recovering 5V μP systems requiring both power and software fault resilience.

Availability

PT7M7825LTAEX is available at Aetrix Electronics and suitable for industrial PLC controllers, network router power management, server baseboard management, and embedded security appliances requiring stable component supply and long-term design continuity.

Supply support for PT7M7825LTAEX 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 is designed specifically for microprocessor system supervision - integrating precision voltage monitoring, watchdog timing, and manual reset into compact, RoHS-compliant packages for embedded power-rail reliability.

FAQ

What is the guaranteed minimum VCC level at which PT7M7825LTAEX asserts RESET?

PT7M7825LTAEX guarantees RESET assertion down to VCC = 1.0V, with RESET remaining valid and low (≤0.4V) throughout this range. This ensures fail-safe reset behavior during deep brownout conditions before logic voltage thresholds are violated, supporting robust system recovery in low-voltage transients.

Does PT7M7825LTAEX require external components for manual reset functionality?

No. PT7M7825LTAEX integrates a 52kΩ internal pull-up resistor on the MR pin, allowing direct connection of a momentary switch between MR and GND without external biasing. The MR input is CMOS-compatible and debounced internally, eliminating the need for RC filters or Schmitt-trigger buffers in typical implementations.

How does the watchdog timer respond to WDI signal transitions?

The watchdog timer clears on every rising or falling edge of the WDI input. If WDI remains static (high or low) for ≥1.6s, the timer expires and triggers a reset. Floating WDI or connecting it to a high-impedance buffer disables the watchdog. Edge detection sensitivity supports pulses as short as 150ns, accommodating tight firmware timing constraints.

What is the significance of the 'L' suffix in PT7M7825LTAEX?

The 'L' suffix denotes a 4.63V nominal reset threshold voltage (VRN), part of Diodes' standardized voltage grade coding. This value targets 5V systems where precise brownout detection is required - distinct from 'M' (4.38V), 'T' (3.08V), or 'S' (2.93V) variants - and is validated across -40°C to +85°C with ±2.5% tolerance.