
Switcher chip provides high accuracy in non-isolated off-line application
The LinkSwitch-TN2 off-line switcher IC for non-isolated applications handles up to 360 mA of output current and can be configured as a buck, buck-boost or a non-isolated flyback converter with high accuracy, high efficiency and excellent no-load performance. The voltage regulation is better than -/+ 3% to eliminate post regulators, minimizing the BOM, increasing efficiency and reducing size. The design requires just 20 additional components to complete a buck converter, and may be configured to use off-the-shelf inductors, further reducing cost and supply chain complexity.
The device incorporates new safety features including input over- and under-voltage protection and a rugged MOSFET with a 725 V breakdown voltage, offering robust output short-circuit and over-temperature protection against line surges and swells. Applications include appliances, HVAC, industrial, home automation (IoT) and metering systems, particularly those destined for India and other geographies where the power grid may not be very stable.
The new devices are efficient in low-power applications – above 80 % in 12 V, 120 mA (1.4 W) buck designs for example, consuming less than 30 mW no-load in a buck arrangement and less than 10 mW when configured as a non-isolated flyback. This is a key tool for designers addressing Total Energy Consumption (TEC) regulations, which prescribe an energy budget limit over a range of operating modes. LinkSwitch-TN2 efficiency performance enables manufacturers to design power supplies to meet worldwide product energy-efficiency requirements.
“Our LinkSwitch-TN2 off-line converter ICs include a selectable cycle-by-cycle current limit which allows designers to choose low-cost inductors and capacitors saving cost and board space, or configure the circuit to output higher power using optimized external components. The new device’s robust 725 V MOSFET allows a typical design to easily withstand 1 kV differential line surges without additional surge suppressors,” said Silvestro Fimiani, senior product marketing manager at Power Integrations.
The LinkSwitch-TN2 ICs come in three different packages: PDIP-8C, SO-8C, and SMD-8C and are available now, priced at $0.60 in 10,000-piece quantities.
Information including reference designs is available from www.power.com/linkswitch-tn2.
