RDK-295

Reference design kit for a 20W standby power supply using TinySwitch™-4 TNY290PG. EcoSmart™ meets all existing and proposed harmonized energy efficiency standards including CECP (China), CEC, EPA, AGO and European commission. Tightly toleranced I2f parameter (–10%, +12%) reduces system cost, increases MOSFET and magnetics power delivery, reduces overload power which lowers output diode and capacitor costs. Integrated TinySwitch-4 safety/reliability features includes accurate (±5%), auto-recovering, hysteretic thermal shutdown function maintains safe PCB temperatures under all conditions, auto-restart protects against output short circuit and open loop fault conditions and <gt/>3.2 mm creepage on package enables reliable operation in high humidity and high pollution environments. Although designed as an auxiliary or bias supply for a personal computer (PC) power supply, this design can also be used as a general-purpose evaluation platform for TinySwitch-4 devices.

• 90VAC to 295VAC (110VDC to 420VDC) input and 5V, 4A output
• No-load consumption of <lt/>40mW at 230VAC
• <gt/>81% active-mode efficiency (exceeds standards requirement of 76%)
• BP/M capacitor value selects MOSFET current limit for greater design flexibility
• Meets EN550022 and CISPR-22 Class B conducted EMI
• Typically used in general PC applications
• Output overvoltage protection (OVP) using primary bias winding sensed shutdown feature