STMicroelectronics TSM007IN

Overview

TSM007IN from STMicroelectronics is a fixed-frequency current-mode PWM controller IC designed for offline and DC-DC SMPS applications, featuring internal UVLO (7.9 V turn-on / 7.3 V turn-off), programmable soft start (10 µA source current), 2 kV ESD protection, and totem-pole output capable of 1 A peak drive for power MOSFETs. It operates from 12–25 V supply across 0–95°C and targets PC ATX and industrial AC/DC adapters.

For engineers reviewing the TSM007IN datasheet, TSM007IN pinout, TSM007IN application, or TSM007IN equivalent, key selection criteria include its 100 kHz nominal oscillator frequency (±2% over supply, ±10% over temperature), 60% typical maximum duty cycle, 1.0 V current sense threshold, 2.5 V brown-out detection, and DIP-8 package compatibility with legacy board layouts.

Technical Context

The TSM007IN implements current-mode control via a dedicated CS input with 3.0 V/V gain and 1.0 V max sensing voltage, synchronized to an internal oscillator whose frequency is set by an external CT capacitor (e.g., 1.5 nF for 100 kHz). The COMP pin serves as error amplifier output interface, setting current limit via (V_COMP − 2×V_BE)/3.

Brown-out protection uses the BRNOUT pin to monitor bulk voltage through a resistor divider; below 2.5 V, the IC disables V_REF, resets soft-start, and forces OUT low. Soft start is implemented via SS pin charging at 10 µA, clamped at 4.2 V, with timing determined by external capacitor (e.g., 210 nF for 50 ms).

Key Specifications

Pinout & Package

Package: Plastic DIP-8 (dual in-line package), 9.8 mm × 8.8 mm body, 2.54 mm lead pitch, through-hole mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PWM controller applications.

Compared with UC3842BD1R2G and TL494CN, the TSM007IN integrates brown-out detection, soft-start, and higher peak output drive-reducing BOM count and improving reliability in compact offline SMPS where current-mode control and robust line monitoring are required.

Availability

TSM007IN is available at Aetrix Electronics and suitable for PC ATX power supplies, industrial AC/DC adapters, LED driver power stages, and embedded system auxiliary supplies requiring stable component supply and long-term obsolescence management.

Supply support for TSM007IN 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, MCU, power, and sensor solutions for automotive, industrial, and consumer markets.

The TSM007IN belongs to ST's legacy power management IC portfolio, engineered specifically for cost-effective, high-reliability offline SMPS in computing and industrial equipment where integration of UVLO, brown-out, and MOSFET drive simplifies primary-side control.

FAQ

What is the minimum recommended CT capacitor value for stable 100 kHz operation?

The datasheet specifies 1.5 nF as the standard CT value for 100 kHz operation, based on 400 µA charge and 600 µA discharge currents and 1.6 V oscillator amplitude. Using <1.2 nF risks frequency drift beyond ±2% tolerance due to process variation; values below 1 nF may cause instability or premature CT pin saturation.

Can the TSM007IN operate with a 5 V supply instead of the specified 12–25 V range?

No. The internal UVLO circuit requires ≥7.9 V to enable operation, and the output driver lacks sufficient headroom below 12 V to deliver 1 A peak current. At 5 V, the OUT stage cannot saturate properly, COMP bias fails, and VREF does not stabilize-resulting in complete functional failure.

How does the BRNOUT pin interact with the soft-start function during recovery from brown-out?

When BRNOUT rises above 2.5 V after a brown-out event, the IC re-enables VREF, asserts the startup latch, and initiates a full soft-start sequence: the SS capacitor discharges fully, then recharges at 10 µA, ramping duty cycle from zero over ~50 ms (with 210 nF). This prevents abrupt restart and inrush into partially discharged bulk capacitors.

Is the TSM007IN pin-compatible with newer STMicroelectronics PWM controllers like the L6565?

No. The L6565 uses SO-16 packaging and features resonant mode control, PFC integration, and different pin assignments (e.g., no BRNOUT or SS pins). TSM007IN's DIP-8 layout and dedicated brown-out/soft-start pins are unique to its legacy generation; direct replacement requires PCB redesign and firmware adaptation.