The IR2161 is a dedicated Intelligent Half bridge Driver IC for a Halogen convertor (electronic transformer). It includes all necessary protection features and also allows the Convertor to be dimmed externally with a standard phase cut dimmer with both leading or trailing edge types. This IC provides the advantage of reduced thermal stress in the lamp due to softstart. There is also compensation of the output voltage for load regulation. It enables the convertor to operate with extremely low harmonic distortion over the full range of loads. The IR2161 includes adaptive deadtime to allow cool running MOSFETs and improves the EMI behaviour due to frequency modulation (dither). All the features are integrated in a small 8 pin DIP/SOIC package to allow for a size reduction in the next generation of convertors.
The IR2161 is an intelligent half‑bridge driver IC designed for halogen (electronic transformer) converters. It integrates protection functions such as auto‑resetting short‑circuit and overload protection, adaptive dead‑time, and a soft‑start feature that reduces lamp inrush current. The device can be dimmed with standard phase‑cut dimmers and includes voltage‑shift compensation for load regulation.
The data sheet provides absolute maximum ratings, recommended operating conditions, and detailed electrical characteristics for both 8‑lead DIP and SOIC packages. It also describes the under‑voltage lock‑out mode, oscillator behavior, and recommended external components such as the CSD compensation capacitor.
| High side floating supply voltage (VB) | -0.3 V to 625 V |
|---|---|
| Maximum power dissipation (8‑Lead DIP) | 1 W |
| Maximum power dissipation (8‑Lead SOIC) | 0.625 W |
| Soft‑start charge current (Iss) | 0.5 mA |
| Recommended CSD compensation capacitor | 100 nF |
UVLO activates when VCC falls below about 5.5 V, keeping the supply current under 300 µA until the IC is fully functional.
The oscillator starts at roughly 130 kHz and then sweeps down to the normal operating range.
The 8‑Lead SOIC version is rated for a maximum dissipation of 0.625 W at 25 °C ambient.
A 100 nF capacitor is recommended for the CSD compensation network.