STMicroelectronics STM6315MDW13F

Overview

STM6315MDW13F from STMicroelectronics is a low-power open-drain microprocessor reset supervisor IC that monitors V_CC and asserts an active-low reset signal when supply voltage falls below 4.38 V (±1.8% at 25°C), with guaranteed RST assertion down to V_CC = 1.0 V. It features manual reset input (MR), power-supply transient immunity, and operates across –40 to +125°C in SOT143-4 package. Used in industrial MCU power-up sequencing and brownout protection.

For engineers reviewing the STM6315MDW13F datasheet, STM6315MDW13F pinout, STM6315MDW13F application, or STM6315MDW13F equivalent, key selection criteria include reset threshold accuracy, open-drain output compatibility with higher-voltage logic rails, t_rec = 210 ms nominal timeout, MR debounce capability, and extended temperature operation up to +125°C.

Technical Context

The STM6315MDW13F implements a precision voltage comparator with factory-trimmed 4.38 V reset threshold and internal reset timer generating a fixed 210 ms (typ) active-low pulse width (t_rec) after V_CC recovery. Its open-drain RST output supports pull-up to voltages up to 6 V - independent of V_CC - enabling interoperability with mixed-voltage systems.

It includes a debounced manual reset input (MR) with 63 kΩ internal pull-up, TTL/CMOS-compatible thresholds, and 100 ns glitch rejection. The device maintains valid RST assertion during negative-going V_CC transients up to 100 µs (at 100 mV overdrive), and draws only 1.5 µA typical supply current at 3.6 V and 25°C.

Key Specifications

Pinout & Package

SOT143-4 (W1) package: 4-pin, small-outline transistor outline with gull-wing leads; JEDEC-compliant, ECOPACK® lead-free, footprint compatible with standard SOT-143 land patterns.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor reset applications.

Compared with MAX6315M37D3+T and TPS3808G33DBVR, the STM6315MDW13F uniquely combines 4.38 V precision threshold, open-drain RST capable of exceeding V_CC, and 1.5 µA ultra-low current - making it optimal for 5 V industrial systems requiring mixed-rail reset signaling and extended temperature resilience.

Availability

STM6315MDW13F is available at Aetrix Electronics and suitable for industrial motor drives, automotive body control modules, and smart energy meters requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for STM6315MDW13F 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 silicon solutions for automotive, industrial, and consumer markets.

The STM63xx series is ST's dedicated family of micropower reset supervisors targeting high-reliability embedded systems where precise voltage monitoring, low power, and robust transient immunity are critical.

FAQ

What is the exact reset threshold voltage for STM6315MDW13F?

The STM6315MDW13F has a factory-trimmed reset threshold of 4.38 V, with ±1.8% accuracy at 25°C. Over the full –40 to +125°C range, the threshold varies by ±3.5%, resulting in a worst-case span of 4.23 V to 4.53 V. This value is confirmed in Table 4 of the official ST datasheet (Rev 5, March 2007) and corresponds to the "M" threshold code in the part numbering scheme.

Can the RST output be pulled up to 5 V while V_CC is 3.3 V?

Yes. The RST pin is an open-drain output rated for up to 6 V on the pull-up rail, regardless of V_CC. When V_CC = 3.3 V, RST can be pulled up to 5 V to interface directly with legacy 5 V logic or mixed-voltage MCUs - no level shifter required. The output remains valid down to V_CC = 1.0 V, and leakage is limited to 1 µA when deasserted.

Does STM6315MDW13F require an external capacitor on the MR pin?

No external capacitor is required for basic MR functionality. The MR input includes an internal 63 kΩ pull-up resistor and built-in 100 ns glitch rejection, allowing direct connection to a momentary switch or logic signal. However, in electrically noisy environments (e.g., motor drives), ST recommends adding a 0.1 µF ceramic capacitor from MR to V_SS to enhance noise immunity - this is specified in Section 2.2 of the datasheet.

What is the minimum V_CC needed to maintain valid RST assertion?

The STM6315MDW13F guarantees RST assertion down to V_CC = 1.0 V. Below this voltage, the RST output transitions to a high-impedance open circuit (no sinking capability). For applications requiring RST to remain low all the way to 0 V, ST recommends adding a 100 kΩ pull-down resistor from RST to V_SS, as described in Section 2.4 of the datasheet.