STRS6707

**The STR-S6707, STR-S6708, and STR-S6709 are specifically designed to

meet the requirement for increased integration and reliability in off-line quasi-resonant flyback converters. These devices incorporate the primary control and proportional drive circuit with a third generation high-voltage bipolar switching transistor.**

Crucial system parameters such as maximum ON time and OFF time are fixed during manufacture. Local control circuit decoupling and layout are optimized within each device. Cycle-by-cycle current limiting, under-voltage lock-out with hysteresis, over-voltage protection, and thermal shutdown protect these devices during all normal and overload conditions. Over-voltage protection and thermal shutdown are latched after a short delay. A versatile triple-level inhibit circuit includes the OFF time synchronization required to establish quasi-resonant operation. The inhibit function has also been expanded to initiate operation in stand-by mode in which the power supply delivers a small fraction of the steady-state output power. The dual requirements of dielectric isolation and low transient thermal impedance and steady-state thermal resistance are satisfied in an over molded single-in-line power package.
Proven in substantial volumes, these devices and their fixed frequency counterparts represent a significant advance in off-line SMPS reliability growth and integration.

FEATURES

■ Quasi-Resonant Operation for Low EMI and High Efficiency
■ Output Power to 220 W
■ Low-Power Output Standby Mode
■ Pulse-by-Pulse Over-Current Protection
■ Latched Over-Voltage and Thermal Protection
■ Third-Generation Switching Transistor with Proportional Drive
■ Maximum ON Time and Off Time Set During Manufacture
■ Internal Under-Voltage Lockout with Hysteresis
■ Over-Molded SIP with Integral Isolated Heat Spreader