Diodes Incorporated PT7M7809TTEX

Overview

PT7M7809TTEX from Diodes Incorporated is a precision 3.08V supply-voltage supervisor IC with push-pull active-low RESET output, 200ms reset pulse width, and guaranteed operation down to VCC = 1.0V. It monitors power-rail integrity during power-up, brownout, and power-down in microprocessor systems, asserting reset until voltage stabilizes above threshold - used in embedded servers and security controllers where deterministic reset timing is critical.

For engineers reviewing the PT7M7809TTEX datasheet, PT7M7809TTEX pinout, PT7M7809TTEX application, or PT7M7809TTEX equivalent, key selection criteria include its fixed 3.08V reset threshold (±2.5% over temperature), manual-reset compatibility, absence of watchdog or MR input (per function table), and SOT23-3 package footprint for space-constrained PCBs.

Technical Context

The PT7M7809TTEX implements a dedicated reset generator with internal timebase for precise 200ms (typ) reset assertion after VCC crosses VRST. Its architecture lacks watchdog timer or manual-reset circuitry - confirmed by Function Comparison Table entry #2 - distinguishing it from PT7M7811/7823 variants.

It features a push-pull RESET output capable of sinking 3.2mA at VCC ≥ 4.5V (VOL ≤ 0.4V), and guarantees valid reset signaling even as VCC drops to 1.0V - enabling robust low-voltage system initialization in battery-backed or energy-harvesting applications.

Key Specifications

Pinout & Package

PT7M7809TTEX is housed in a 3-pin SOT23 plastic package (Ordering Info: T code), with pins arranged as VCC, GND, and RESET. The compact 2.9mm × 1.6mm footprint supports high-density layout in space-constrained applications such as network interface cards and IoT edge nodes.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with APX809S-30TSG-7 and TPS3809K33DBVR, PT7M7809TTEX offers the exact 3.08V threshold needed for legacy 3.3V systems with margin-sensitive brownout detection, while maintaining lowest quiescent current (10µA) and direct pin compatibility in SOT23-3 layouts.

Availability

PT7M7809TTEX is available at Aetrix Electronics and suitable for industrial PLC controllers, network-attached storage units, smart surveillance cameras, and medical diagnostic handhelds requiring stable component supply throughout product lifecycles.

Supply support for PT7M7809TTEX 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 solutions, with design and manufacturing facilities certified to IATF 16949 and ISO 9001 standards.

The PT7M78xx family targets microprocessor power-supply monitoring, reducing component count and improving reliability in embedded systems through integrated reset generation, voltage thresholding, and watchdog functions - though PT7M7809TTEX implements only the core reset function.

FAQ

What is the reset threshold voltage for PT7M7809TTEX and how tightly is it specified?

The PT7M7809TTEX has a nominal reset threshold of 3.08V, with ±2.5% tolerance over the full operating temperature range (-40°C to +85°C). This specification is guaranteed by design and validated across process corners, ensuring consistent brownout detection on 3.3V rails without requiring external calibration.

Does PT7M7809TTEX include a watchdog timer or manual reset input?

No. Per the Function Comparison Table (entry #2), PT7M7809TTEX provides only power-on/power-down/brownout reset generation with no watchdog timer (WDI) or manual-reset (MR) input functionality. It is a minimal-feature variant optimized for cost-sensitive applications where only voltage monitoring is required.

Can PT7M7809TTEX operate reliably at very low supply voltages?

Yes. The device guarantees valid RESET output behavior down to VCC = 1.0V, with VOL ≤ 0.4V at VCC ≥ 4.5V and functional reset assertion even as VCC drops below 2.0V. This enables robust operation during deep brownout and controlled power-down sequences in battery-powered systems.

What package type and pin configuration does PT7M7809TTEX use?

PT7M7809TTEX uses the SOT23-3 plastic package (Ordering Code T), with pin 1 = VCC, pin 2 = GND, and pin 3 = RESET. The 3-pin configuration matches industry-standard footprint for voltage supervisors, enabling drop-in replacement in existing designs using compatible SOT23-3 footprints.