Diodes Incorporated PT7M3808G09TAEX

Overview

PT7M3808G09TAEX from Diodes Incorporated is a low-quiescent-current, programmable-delay supervisory IC with fixed 0.84 V voltage detection threshold and open-drain RESET output. It monitors supply rails in space-constrained embedded systems, provides 20 ms or 300 ms reset delay (via CT pin configuration), draws only 5.0 µA typical supply current at 3.3 V, and operates across –40°C to +125°C. Used for reliable power-on reset in microcontroller-based IoT sensor nodes.

For engineers reviewing the PT7M3808G09TAEX datasheet, PT7M3808G09TAEX pinout, PT7M3808G09TAEX application, or PT7M3808G09TAEX equivalent, key selection criteria include its 0.84 V SENSE threshold accuracy, 20/300 ms selectable delay timing, SOT23-6 package footprint, open-drain RESET drive capability, and ultra-low IDD of 5.0 µA - all critical for battery-powered edge devices requiring long-term reliability.

Technical Context

The PT7M3808G09TAEX implements a precision bandgap-based voltage detector with 2.5% hysteresis on the SENSE input, ensuring noise-immune reset assertion/deassertion. Its MR pin features an internal 90 kΩ pull-up resistor, enabling manual reset without external components.

Reset delay is determined by the CT pin: open-circuit yields 20 ms, connection to VDD via 40–200 kΩ yields 300 ms, and capacitor coupling (≥100 pF) enables user-programmable delays from 0.75 ms to 1.7 s. The open-drain RESET output supports rail-to-rail voltage translation up to 6.5 V with external pull-up.

Key Specifications

Pinout & Package

SOT23-6 package with exposed thermal pad (connected to GND); 2.9 mm × 2.8 mm × 1.3 mm body, 0.95 mm pitch; RoHS-compliant, halogen- and antimony-free "Green" construction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G09DBVR and MAX6326LT29D2T, the PT7M3808G09TAEX offers tighter VIT tolerance (±3% vs ±3.5%), dual factory-set delays without external components, and integrated MR pull-up - delivering higher timing precision and lower BOM cost in resource-constrained designs.

Availability

PT7M3808G09TAEX is available at Aetrix Electronics and suitable for smart metering modules, industrial PLC I/O cards, and wireless sensor nodes requiring stable component supply, long-lifecycle support, and guaranteed RoHS 3 compliance.

Supply support for PT7M3808G09TAEX 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, automotive, and consumer markets.

The PT7M3808 series belongs to Diodes' precision supervisory IC product line, engineered specifically for ultra-low-power, high-accuracy voltage monitoring in battery-powered and thermally demanding embedded systems.

FAQ

What is the exact VIT threshold and tolerance for PT7M3808G09TAEX?

The PT7M3808G09TAEX has a nominal SENSE threshold voltage (VIT) of 0.84 V, with a guaranteed range of 0.81 V to 0.844 V across –40°C to +125°C. This corresponds to ±3% tolerance relative to the typical value, verified per Electrical Characteristics table in DS43298 Rev 8-2.

Can the CT pin be left floating to achieve the 20 ms delay?

Yes - the CT pin must be left open (unconnected) to select the 20 ms reset delay mode. The datasheet explicitly states "leaving it open results in fixed delay times 20ms." Floating is electrically identical to open-circuit in this context and is the intended configuration for that timing option.

Does PT7M3808G09TAEX support manual reset without an external pull-up on MR?

Yes - the MR pin includes an internal 90 kΩ pull-up resistor to VDD, so no external component is needed to hold MR high under normal operation. Driving MR low externally will assert RESET; the internal pull-up ensures automatic deassertion when the external signal is released.

Is the thermal pad on the SOT23-6 package required to be soldered to ground?

Yes - the exposed thermal pad (PAD) must be connected to the PCB ground plane to ensure proper thermal performance and meet the specified junction temperature limits. The datasheet states "Connect to ground plane to enhance thermal performance of package," and omitting this connection risks exceeding TJ max under sustained load.