STMicroelectronics STM6718TWWY6F

Overview

STM6718TWWY6F from STMicroelectronics is a dual ultra-low-voltage supervisor IC with push-button reset, monitoring VCC1 (primary supply) and VCC2 (secondary supply), featuring factory-programmed reset thresholds of 4.63 V and 3.08 V respectively, 13.2 ms/210 ms/900 ms selectable power-up reset delay, active-low push-pull RST output, and guaranteed operation down to VCC ≥ 0.8 V - used in set-top boxes, portable battery-powered systems, and networking equipment.

For engineers reviewing the STM6718TWWY6F datasheet, STM6718TWWY6F pinout, STM6718TWWY6F application, or STM6718TWWY6F equivalent, key selection considerations include dual-supply monitoring capability, push-pull RST output compatibility with microprocessor reset inputs, manual reset timing behavior, and SOT23-5 package constraints for space-constrained embedded designs.

Technical Context

The device implements independent voltage comparators for VCC1 and VCC2 against fixed internal thresholds, with logic arbitration ensuring RST remains asserted low until both supplies exceed their respective thresholds and MR returns high. Reset assertion is guaranteed when either VCC1 or VCC2 ≥ 0.8 V, enabling reliable reset generation during brown-out recovery.

It integrates a dedicated MR input with internal 50 kΩ pull-up, supporting direct connection to momentary switches without external debounce; RST output is push-pull (not open-drain), referenced to VCC1, eliminating need for external pull-up resistors in most host processor interfaces.

Key Specifications

Pinout & Package

STM6718TWWY6F is housed in a SOT23-5 (WY) surface-mount package - compact, thermally efficient, and compatible with standard reflow processes. Pin 1 is RST (active-low push-pull reset output), Pin 2 is VCC1 (primary supply monitor input), Pin 3 is VCC2 (secondary supply monitor input), Pin 4 is MR (manual reset input), and Pin 5 is VSS (ground).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-supply supervisor applications.

Compared with TPS3808G18DBVR and MAX6816EUT+T, STM6718TWWY6F uniquely integrates dual independent voltage comparators, factory-trimmed thresholds, and push-pull RST in a single SOT23-5 package - reducing BOM count and PCB area while guaranteeing coordinated reset across two critical power domains.

Availability

STM6718TWWY6F is available at Aetrix Electronics and suitable for set-top boxes, portable medical monitors, and industrial Ethernet gateways requiring stable component supply, long-term lifecycle support, and guaranteed industrial-temperature performance.

Supply support for STM6718TWWY6F 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and analog products for industrial, automotive, and consumer markets.

STM67xx is ST's ultra-low-voltage supervisor product line targeting space- and power-constrained embedded systems requiring dual-rail monitoring, push-button reset, and guaranteed reset assertion down to 0.8 V supply - optimized for consumer electronics and networking infrastructure.

FAQ

What is the function of the MR pin on STM6718TWWY6F?

The MR (Manual Reset) pin is an active-low input with an internal 50 kΩ pull-up resistor. When pulled to ground via a momentary switch, it forces the RST output low immediately. RST remains low for the full reset delay period (trec) after MR returns high, ensuring reliable processor reset initiation without external debounce circuitry.

Can STM6718TWWY6F monitor a 1.8 V supply?

No - STM6718TWWY6F has factory-programmed VCC1 and VCC2 thresholds of 4.63 V and 3.08 V, respectively. It cannot monitor 1.8 V directly. For sub-3 V rails, ST offers variants like STM6720 (with adjustable RSTIN input using 0.626 V internal reference), but STM6718 lacks RSTIN and fixed thresholds are not user-adjustable.

Is the RST output truly push-pull, and what does that imply for MCU interface?

Yes - RST is a true active-low push-pull output referenced to VCC1. It actively drives low and high states without external components. This eliminates the need for a pull-up resistor and ensures fast, robust reset signaling to MCUs with standard reset inputs, unlike open-drain alternatives that require careful pull-up sizing and suffer from slower rise times.

Does STM6718TWWY6F support delayed manual reset (MRC functionality)?

No - MRC (Manual Reset Delay) is only available on STM6777/78/79/80 variants in the same family. STM6718TWWY6F belongs to the STM6717/18/19/20 series and lacks the MRC pin entirely. Manual reset assertion is immediate upon MR activation, with release delayed only by the fixed trec period after MR deassertion.