Diodes Incorporated PT7M7809RTEX

Overview

PT7M7809RTEX from Diodes Incorporated is a precision 2.63V microprocessor supervisory circuit with push-pull active-low RESET output, 200ms reset pulse width, and guaranteed operation down to VCC = 1.0V. It monitors supply voltage during power-up, brownout, and power-down in embedded μP systems, asserting reset to ensure deterministic startup and fault recovery in industrial controllers and network edge devices.

For engineers reviewing the PT7M7809RTEX datasheet, PT7M7809RTEX pinout, PT7M7809RTEX application, or PT7M7809RTEX equivalent, key selection criteria include its fixed 2.63V reset threshold (±2.5% over –40°C to +85°C), manual-reset input compatibility, absence of watchdog or MR pull-up (unlike PT7M7811/7823), and SOT23-3 package footprint for space-constrained PCBs.

Technical Context

The PT7M7809RTEX implements a voltage-monitoring architecture with hysteresis (50mV typical) to prevent oscillatory reset assertion near the 2.63V threshold. Its internal timebase generates a fixed 200ms (140–400ms) reset pulse after VCC rises above VRST or after MR release, independent of external components.

No watchdog timer or manual-reset pull-up resistor is integrated - it relies on external circuitry for MR activation and lacks WDI functionality, distinguishing it from PT7M7823/7825 variants. The push-pull RESET output drives low to ≤0.4V at 3.2mA sink current, enabling direct interface with μP reset inputs without external pull-ups.

Key Specifications

Pinout & Package

PT7M7809RTEX is housed in a 3-pin SOT23-3 plastic package (JEDEC TO-236AB), 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 voltage supervisor applications.

Compared with APX809S-26SA-7 and TPS3809K26DBVR, PT7M7809RTEX offers the only combination of guaranteed 1.0V operation, push-pull RESET, and zero additional features - making it optimal for minimal-footprint, ultra-low-power μP supervision where MR and watchdog are handled externally.

Availability

PT7M7809RTEX is available at Aetrix Electronics and suitable for industrial PLC controllers, network edge routers, embedded security gateways, and server management controllers requiring stable component supply and long-term obsolescence planning.

Supply support for PT7M7809RTEX 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 semiconductor company specializing in discrete, analog, and mixed-signal ICs for power management, signal integrity, and protection applications.

The PT7M78xx family is designed specifically for μP system reliability - reducing component count and improving accuracy in power-supply monitoring for embedded, networking, and industrial control applications.

FAQ

What is the exact reset threshold voltage and tolerance for PT7M7809RTEX?

The PT7M7809RTEX has a nominal reset threshold of 2.63V, with a guaranteed tolerance of ±2.5% over the full operating temperature range (–40°C to +85°C). This value is confirmed in the DC Electrical Characteristics table of the official Diodes datasheet (Document Number 43008 Rev 2-4), and applies to both rising and falling VCC transitions with 50mV typical hysteresis.

Does PT7M7809RTEX include a watchdog timer or manual-reset pull-up resistor?

No. PT7M7809RTEX does not integrate a watchdog timer or internal MR pull-up resistor. Unlike PT7M7823 or PT7M7811, it provides only voltage monitoring and reset generation. Manual reset requires an external pull-up or switch-to-ground configuration, and watchdog functionality is absent - confirmed by the Function Comparison Table and Pin Description section of the datasheet.

What package type and lead finish does PT7M7809RTEX use?

PT7M7809RTEX uses the SOT23-3 (TO-236AB) package with gull-wing leads, marked "T" in Diodes' ordering information. It features a totally lead-free, RoHS 3-compliant (2015/863/EU) finish, halogen- and antimony-free per Diodes' green definition, and is supplied in tape-and-reel format (suffix "XTEX").

Can PT7M7809RTEX operate reliably below 2.0V supply voltage?

Yes. PT7M7809RTEX guarantees valid RESET/RESET output behavior down to VCC = 1.0V, as explicitly stated in the datasheet's Features list and DC Electrical Characteristics table. This allows robust reset assertion during deep brownout conditions common in battery-backed or energy-harvesting systems.