L6565 is a current-mode primary controller IC, specifically designed to build offline Quasi-resonant ZVS (Zero Voltage Switching at switch turn-on) fly-back converters. Quasi-resonant operation is achieved by means of a transformer demagnetization sensing input that triggers MOSFET's turn-on.
The L6565 controller implements a quasi‑resonant (QR) zero‑voltage‑switching topology with line‑feed‑forward regulation, providing constant power despite mains variations. It features ultra‑low start‑up (<70 µA) and quiescent (<3.5 mA) currents, a 1 % precision internal reference, and a totem‑pole gate driver capable of 400 mA peak current.
The device includes a disable function, pulse‑by‑pulse over‑current protection, zero‑current detection, and frequency fold‑back. It is intended for offline flyback converters used in TV/monitor SMPS, AC‑DC adapters, printers, fax machines, photocopiers, scanners and similar consumer electronics.
| Supply Voltage Range (VEE) | 10.3 V – 18 V |
|---|---|
| Quiescent Current (after turn‑on) | 2.3 mA – 3.5 mA |
| Gate Driver Peak Current | 400 mA |
| Junction Temperature Range | -40 °C – 150 °C |
| Power Dissipation (Tj=50 °C) | 1 W (Minidip) |
| Thermal Resistance, Junction‑to‑Ambient | 150 °C/W (max) |
The totem‑pole gate driver can source or sink up to 400 mA.
The L6565 operates from –40 °C up to 150 °C junction temperature.
Yes, the device includes a disable function that shuts down the IC when the disable pin voltage falls below 150 mV.