The LNK626DG is an energy-efficient offline Switcher with accurate primary-side constant-voltage (CV) control. The LinkSwitch-CV dramatically simplifies low power, constant voltage converter design through a revolutionary control technique which eliminates the need for both an optocoupler and secondary CV control circuitry while providing very tight output voltage regulation. The combination of proprietary IC trimming and E-Shield™ transformer construction techniques enables Clampless™ designs with the LinkSwitch-CV LNK623. LinkSwitch-CV provides excellent cross-regulation for multiple-output fly-back applications such as DVDs and STBs. A 700V power MOSFET and ON/OFF control state machine, self-biasing, frequency jittering, cycle-by-cycle current limit and hysteretic thermal shutdown circuitry are all incorporated onto one IC.
Feature
- Eliminates optocoupler and all secondary CV/CC control circuitry
- Eliminates bias winding supply - IC is self biasing
- Compensates for external component temperature variations
- Very tight IC parameter tolerances using proprietary trimming technology
- Continuous or discontinuous mode operation for design flexibility
- Frequency jittering greatly reduces EMI filter
- Even tighter output tolerances achievable with external resistor selection/trimming
- Hysteretic thermal shutdown - Automatic recovery reduces power supply returns from the field
- Easily meets all global energy efficiency regulations with no added components
- No primary or secondary current sense resistors - Maximizes efficiency
- Auto-restart protection reduces power delivery by >95% for output short-circuit/control loop faults
- No-load consumption below 200mW at 230VAC and down to below 70mW with optional external bias
