Diodes Incorporated PT7M6139NLC4EX

Overview

PT7M6139NLC4EX from Diodes Incorporated is a precision ultra-low-power voltage detector with 3.9V threshold, N-channel open-drain active-low output, ±1.5% accuracy at 25°C, 1μA supply current at 3.6V, and 17µs propagation delay. It monitors VCC in battery-powered microcontrollers, portable sensors, and power-management circuits where reliable brown-out detection is required.

For engineers reviewing the PT7M6139NLC4EX datasheet, PT7M6139NLC4EX pinout, PT7M6139NLC4EX application, or PT7M6139NLC4EX equivalent, key selection criteria include threshold accuracy over temperature (±2.5% max), hysteresis (4.5% typ), open-drain drive capability (1mA sink), SC70-4 package footprint, and compatibility with 1.2V–5.5V supply rails.

Technical Context

The PT7M6139NLC4EX implements a precision bandgap reference (1.25V) and comparator with internally trimmed resistor networks to set VTH− = 3.9V and VTH+ = 4.095V (5% hysteresis). Its internal hysteresis prevents output chatter during slow-rising/falling supply transitions.

It operates across −40°C to +85°C with guaranteed detection performance, uses no external components, and asserts RST low when VCC drops below 3.9V, holding reset until VCC exceeds 4.095V - enabling robust power-on reset and brown-out protection in space-constrained embedded systems.

Key Specifications

Pinout & Package

PT7M6139NLC4EX is housed in a 4-pin SC70 (SOT343) package - compact (2.0mm × 2.1mm × 0.9mm), lead-free, and RoHS-compliant - optimized for high-density PCB layouts in portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with APX803S-39SA-7 and TPS3808G39DBVR, PT7M6139NLC4EX uniquely combines SC70-4 packaging, true open-drain output, and sub-1.1μA supply current - making it optimal for multi-rail reset arbitration and ultra-long-life battery designs where board area and power are co-constrained.

Availability

PT7M6139NLC4EX is available at Aetrix Electronics and suitable for battery-powered wearables, industrial sensor nodes, medical diagnostic handhelds, and smart metering modules requiring stable component supply, long-lifecycle support, and consistent parametric performance.

Supply support for PT7M6139NLC4EX 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 integrated circuits, specializing in high-performance, energy-efficient solutions for power management, signal integrity, and protection.

The PT7M61xx series was designed specifically for ultra-low-power voltage supervision in portable and embedded systems - delivering precision threshold detection without external components or calibration.

FAQ

What is the function of the NC pin on PT7M6139NLC4EX?

The NC (No Connect) pin is an unconnected terminal in the SC70-4 package. It is not bonded to the die and serves no electrical function. Per Diodes Incorporated's datasheet, this pin must remain unconnected - no routing, grounding, or thermal pad connection is permitted, as doing so may compromise device reliability or parametric performance.

Can PT7M6139NLC4EX be used with a 1.8V supply rail?

Yes - PT7M6139NLC4EX operates down to 1.2V, so it fully supports 1.8V supply monitoring. At 1.8V, its 3.9V threshold is not active, but the device remains functional and draws only ~1.1μA. For 1.8V rails, use PT7M6118NLC4EX (1.8V threshold) instead; PT7M6139NLC4EX is intended for 3.3V/3.6V/4.0V systems where 3.9V detection is required.

Does PT7M6139NLC4EX require an external pull-up resistor on the RST pin?

Yes - because RST is an N-channel open-drain output, an external pull-up resistor (typically 10kΩ to 3.3V or 5V) is mandatory to establish a valid high state when the output is inactive. Without it, RST floats undefined, risking spurious resets or failure to release the MCU from reset after VCC recovery.

How does hysteresis improve system reliability in PT7M6139NLC4EX?

Hysteresis (VTH+ = 4.095V, VTH− = 3.9V) creates a 195mV voltage window between reset assertion and release. This prevents rapid toggling of RST during slow or noisy VCC recovery - such as during battery warm-up or light-load regulation - ensuring the MCU receives one clean, sustained reset pulse rather than repeated glitches that could corrupt memory or firmware execution.