Description
The TOP209/210 implements all functions necessary for an off-line switched mode control system: high voltage N-channel power MOSFET with controlled turn-on gate driver, voltage mode PWM controller with integrated oscillator, high voltage start-up bias circuit, bandgap derived reference, bias shunt regulator/error amplifier for loop compensation and fault protection circuitry. Compared to discrete MOSFET and controller or self oscillating (RCC) switching converter solutions, a TOPSwitch integrated circuit can reduce total cost, component count, size, weight and at the same time increase efficiency and system reliability. The TOP209/210 are intended for 100/110/230 VAC off-line Power Supply applications in the 0 to 8 W (0 to 5 W universal) range.

Product Highlights
Cost Effective Switcher for Low Power Applications
• Replaces linear power supplies
• Replaces discrete switcher and 20 to 50 components
   – cuts cost, increases reliability
• Stand-by power supplies for Green or energy efficient
   products such as personal computers, monitors, UPS,
   copiers, fax machines, etc.
• Housekeeping or "keep-alive" power supply applications
   such as TV, appliances, industrial control and personal
   computers
• Meets Blue Angel low power stand-by specification
• Controlled MOSFET turn-on reduces EMI and EMI filter
   costs
• 80% smaller and lighter compared to linear supply
• 50% smaller compared to discrete switcher

Over 80% Efficiency in Flyback Topology
• Built-in start-up and current limit reduce DC losses
• Low capacitance 700 V MOSFET cuts AC losses
• CMOS controller/gate driver consumes only 6 mW
• 70% maximum duty cycle minimizes conduction losses

Simplifies Design – Reduces Time to Market
• Supported by reference design boards
• Integrated PWM Controller and 700 V MOSFET in
   industry standard eight pin DIP package
• Only one external capacitor needed for compensation,
   bypass and start-up/auto-restart functions
• Easily interfaces with both opto and primary feedback

System Level Fault Protection Features
• Auto-restart and cycle by cycle current limiting functions
   handle both primary and secondary faults
• On-chip thermal shutdown with hysteresis protects the
entire system against overload