STMicroelectronics TSM109ID

Overview

TSM109ID from STMicroelectronics is a dual comparator with integrated 2.5 V shunt voltage reference in SO-8 package. It operates from ±1 V to ±18 V supply, delivers ±1 mV typical input offset voltage, 25 nA typical input bias current, and 250 mV typical low-level output saturation voltage at 4 mA sink load-enabling precision overvoltage monitoring in industrial power supplies.

For engineers reviewing the TSM109ID datasheet, TSM109ID pinout, TSM109ID application, or TSM109ID equivalent, key selection considerations include its dual-comparator architecture with one input internally tied to the 2.5 V reference, wide common-mode range (0 V to V_CC − 1.5 V), and guaranteed operation from −40 °C to +105 °C.

Technical Context

The TSM109ID integrates two independent comparators sharing a single 2.5 V precision shunt reference. One comparator's inverting input is hardwired to the internal reference, forming a dedicated threshold detector; the other comparator remains fully configurable with external inputs.

Its PNP-input stage ensures constant 25 nA typical input bias current flowing out of both inputs-eliminating charge injection on sensing nodes-and supports rail-to-rail differential input voltage up to the full supply range (±36 V absolute max).

Key Specifications

Pinout & Package

SO-8 package (JEDEC MS-012AC), surface-mount, 1.27 mm pitch, thermal resistance R_thJA = 175 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-comparator-with-reference applications.

Compared with TLV431AIDBVR and LM393DR, the TSM109ID uniquely combines matched reference and dual comparators in one SO-8 die-delivering lowest system-level error, smallest footprint, and fastest time-to-prototype for fixed-threshold power monitoring.

Availability

TSM109ID is available at Aetrix Electronics and suitable for industrial power supply monitoring, PLC input conditioning, battery management systems, and motor drive protection requiring stable component supply across extended temperature ranges.

Supply support for TSM109ID 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 devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

The TSM109ID belongs to ST's precision analog monitoring product line, engineered specifically for space-constrained, high-reliability power management applications where integration, accuracy, and temperature stability are critical.

FAQ

Can TSM109ID operate from a single 3.3 V supply?

Yes. The device supports single-supply operation from +2 V to +36 V (V_CC to GND). At 3.3 V, the 2.5 V reference remains active and stable, and both comparators function with input common-mode range from 0 V to 1.8 V-sufficient for monitoring 3.3 V rail with appropriate resistor dividers.

How is the internal 2.5 V reference connected to the comparators?

The inverting input of Comparator 2 (Pin 3) is permanently wired to the internal 2.5 V reference cathode (Pin 7). Comparator 1 (Pins 2 and 4) is fully independent. The reference cathode (Pin 7) must be externally loaded with 1–100 mA to regulate; no external reference component is needed.

What is the maximum sink current per output, and can outputs be wire-OR'd?

Each open-collector output sinks up to 20 mA continuously. Outputs can be safely wire-OR'd using a shared pull-up resistor-commonly used to generate a single fault flag from both comparators-but ensure total sink current stays within 20 mA per output under worst-case conditions.

Does TSM109ID require input filtering for noisy environments?

Yes. While the comparator has 200 V/mV gain, its 1.3 µs small-signal response makes it susceptible to noise-induced false triggering. A 10 nF capacitor across the sense resistor divider (or RC filter at Pin 2/Pin 4) is recommended for 50/60 Hz and switching noise suppression in industrial settings.