STMicroelectronics TSM1011ID

Overview

TSM1011ID from STMicroelectronics is a constant voltage (CV) and constant current (CC) controller IC for secondary-side regulation in flyback adapters and battery chargers. It integrates two transconductance op-amps with ORed outputs, a 2.545 V precision voltage reference (±0.5% for TSM1011A, ±1% for TSM1011), operates from 4.5 V to 28 V supply, supports 0–105 °C ambient, and delivers up to 50 mA sink output current.

For engineers reviewing the TSM1011ID datasheet, TSM1011ID pinout, TSM1011ID application, or TSM1011ID equivalent, this device is selected for precise dual-loop feedback in isolated AC/DC power supplies where tight CV/CC regulation, low external component count, and ESD-hardened operation (2 kV) are required.

Technical Context

The TSM1011ID implements independent CV and CC control loops using two internally matched transconductance op-amps sharing a common collector output stage - enabling hardware ORing of voltage and current error signals. Its fixed 2.545 V reference feeds both loops, eliminating need for external reference ICs.

Each op-amp features fully accessible inputs and outputs for external compensation (e.g., 22 kΩ + 2.2 nF networks), supports input common-mode ranges up to V_CC − 1.5 V (CV amp) or 0–V_CC − 1.5 V (CC amp), and provides 70–85 dB CMRR with 65–100 dB supply rejection over 4.5–28 V supply range.

Key Specifications

Pinout & Package

Package: SO-8 (Small Outline, 150 mil width), RoHS-compliant ECOPACK®.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant voltage and constant current control applications.

Compared with TL431LIQDBZRQ1 and UCC3803D, the TSM1011ID uniquely integrates both CV and CC control paths with a shared reference and ORed output-reducing component count by ≥4 and simplifying compensation for secondary-side flyback systems.

Availability

TSM1011ID is available at Aetrix Electronics and suitable for USB-C PD adapters, lithium-ion battery chargers, and industrial AC/DC power supplies requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for TSM1011ID 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 ICs, sensors, and analog components for industrial, automotive, and consumer markets.

The TSM1011ID belongs to ST's dedicated power management analog portfolio, engineered specifically for secondary-side CV/CC regulation in isolated SMPS - prioritizing integration, precision, and robustness in cost-sensitive adapter and charger designs.

FAQ

What is the maximum allowable VCC voltage for continuous operation?

The TSM1011ID has an absolute maximum VCC rating of 28 V, enforced by an internal Zener clamp. Continuous operation above 28 V will trigger the clamp, limiting dissipation to safe levels. For reliable long-term use, VCC should be maintained ≤26 V under worst-case conditions to avoid thermal stress on the clamp structure.

Can the TSM1011ID regulate both voltage and current simultaneously in the same circuit?

Yes - its two transconductance op-amps operate independently but share a common collector output (OUT pin). When either CV or CC loop detects an error, it pulls OUT low, activating the optocoupler and reducing primary-side duty cycle. This hardware ORing ensures simultaneous enforcement of both limits without software intervention.

Is external compensation mandatory for stable operation?

No - the TSM1011ID is unconditionally stable with no external compensation, but loop bandwidth and transient response are suboptimal. External RC networks (e.g., 22 kΩ + 2.2 nF per loop) are recommended to achieve ≥10 kHz closed-loop bandwidth and <5% overshoot during 50–100% load steps.

How does the VRef pin function in current-sense configuration?

VRef supplies the reference voltage for both CV and CC loops. In current sensing, a resistor divider from VRef sets the threshold voltage applied to CC+; the voltage drop across the sense resistor (Rsense) is compared against this threshold at CC−, enabling precise current limit setting independent of output voltage.