Power Integrations Launches LinkSwitch®-CV Constant-Voltage Primary-Side Offline Switcher IC Family

Power Integrations announced additions to its LinkSwitch family of ac-dc switched-mode power conversion ICs. The new LinkSwitch-CV series of devices includes the LNK626PG, described as the world’s highest-power accurate constant voltage (CV) integrated switcher IC with primary-side control. The new devices target applications requiring +/-5% voltage accuracy, such as ac-dc adapters up to 10W, auxiliary power supplies for appliances up to 17W and multiple-output supplies for consumer products.

LinkSwitch-CV integrated circuits are said to simplify the design of CV converters by eliminating all secondary-side CV and control-loop compensation circuitry, significantly reducing the system cost. The company claims that system reliability is greatly increased by the elimination of the optocoupler. Moreover, the new devices are said to feature extremely high energy efficiency, beating ENERGY STAR 2.0 specifications for external power supplies by 10% across the entire load range and consuming under 70mW in no-load mode. The new devices combine a 700V power MOSFET, on/off control state machine, self-biasing circuit, frequency jittering, cycle-by-cycle current limit and hysteretic thermal shutdown circuitry.

Silvestro Fimiani, Product Manager at Power Integrations, commented, "The LinkSwitch-CV dramatically simplifies the design of constant-voltage offline power converters. The high power level achievable with the LinkSwitch-CV is due to continuous conduction mode operation, which optimizes utilization of the integrated transistor. The 700V MOSFET rating allows clampless designs using the LinkSwitch-CV LNK623 and LNK624, further reducing system cost. LinkSwitch-CV provides excellent cross-regulation for multiple-output flyback applications, such as DVDs, set-top boxes and auxiliary power supplies used in appliances."

All LinkSwitch-CV family members are produced in halogen-free, RoHS-compliant packaging. LinkSwitch-CV IC packages feature a high creepage distance to the high-voltage drain pin which improves reliability in white goods and industrial applications. LinkSwitch-CV devices are available immediately from $0.64 ea in 10,000 unit quantities.