STMicroelectronics STM811TW16F

Overview

STM811TW16F from STMicroelectronics is a precision industrial-grade voltage supervisor IC with active-low reset (RST), manual reset input (MR), and 2.85 V to 3.00 V reset threshold. It delivers 140 ms minimum reset pulse width, 6 µA typical supply current, and guaranteed RST assertion down to VCC = 1.0 V. Used in microcontroller power-up sequencing for embedded industrial controllers requiring reliable brownout detection.

For engineers reviewing the STM811TW16F datasheet, STM811TW16F pinout, STM811TW16F application, or STM811TW16F equivalent, key selection criteria include reset threshold accuracy across –40 °C to +85 °C, MR input debounce capability, SOT143-4 package compatibility, and push-pull RST drive strength under low-VCC conditions.

Technical Context

The STM811TW16F implements a precision voltage comparator with internal reference and a programmable reset timer (trec ≥ 140 ms). Its MR input features a 20 kΩ internal pull-up resistor and 100 ns glitch immunity, enabling direct connection to push-button switches without external components.

It guarantees valid RST output down to VCC = 1.0 V over full temperature range and supports stable operation across 1.2 V to 5.5 V supply, with reset threshold temperature coefficient of 45 ppm/°C at VCC = 3.3 V - critical for thermal stability in unregulated 3.3 V systems.

Key Specifications

Pinout & Package

SOT143-4 (W1) package: 4-pin small outline transistor package with 1.92 mm lead pitch, 2.8 mm × 2.1 mm body, and ECOPACK® RoHS-compliant construction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TRD3+T and TPS3808G12QDBVRQ1, the STM811TW16F uniquely combines SOT143-4 compactness, integrated MR input with internal pull-up, and industrial temperature support - delivering optimal BOM and layout efficiency for cost-sensitive 3.3 V embedded controllers.

Availability

STM811TW16F is available at Aetrix Electronics and suitable for industrial PLC I/O modules, smart energy meters, and factory automation HMIs requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for STM811TW16F 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 analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The STM8xx series is ST's dedicated family of low-power voltage supervisors targeting robust power-on reset and brownout protection in resource-constrained embedded systems - optimized for industrial reliability and minimal external component count.

FAQ

What is the exact reset threshold voltage range for STM811TW16F?

The STM811TW16F has a guaranteed reset threshold range of 2.85 V to 3.00 V at –40 °C to +85 °C, corresponding to the "S" grade designation per ST's ordering scheme. At 25 °C, the typical threshold is 2.93 V, with ±30 mV tolerance. This is validated in Table 5 of Doc ID 9873 Rev 5 under VRST specifications for STM8XXS devices.

Does STM811TW16F require an external pull-up resistor on the MR pin?

No. The MR pin includes a factory-trimmed 20 kΩ internal pull-up resistor, confirmed in Section 2.2 and Table 5 of the datasheet. This allows direct connection of a normally open push-button switch between MR and GND without external components. Leaving MR unconnected defaults it to high, disabling manual reset.

Can STM811TW16F operate reliably at VCC = 1.2 V?

Yes. The device is specified to operate across VCC = 1.2 V to 5.5 V (Table 4), and its RST output is guaranteed functional down to VCC = 1.0 V (Section 2.1). At 1.2 V, reset assertion remains valid, though trec may extend slightly beyond 140 ms - verified in Figure 10 for the S/T grade at low VCC.

What is the maximum capacitive load the RST output can drive?

The RST output is a push-pull driver rated for 20 mA sink/source (Table 3), but practical capacitive loading is limited by rise/fall time and noise immunity. ST recommends keeping total load ≤ 50 pF for clean edges; for higher capacitance (e.g., long traces), a series resistor (10–100 Ω) is advised. No explicit C_L limit is given, but Figure 13 shows test conditions with negligible external capacitance.