LTC3900

Supply Voltage
V_CC..........................................................................................12V
Input Voltage
CS, TIMER..................................................0.3V to (V_CC+0.3V)
SYNC.........................................................................12V to 12V
Input Current
CS⁺.......................................................................................15mA
Operating Temperature Range (Note 2)..............40°C to 85°C
Storage Temperature Range.............................65°C to 150°C
Lead Temperature (Soldering, 10 sec)................................300°C

The LTC^®3900 is a secondary-side synchronous recti fierdriver designed to be used in isolated forward converter power supplies. The chip drives N-channel rectifier MOSFETs and accepts pulse sychronization from the primary-side controller via a pulse transformer.

The LTC3900 incorporates a full range of protection for the external MOSFETs. A programmable timeout function is included that disables both drivers when the synchroniza- tion signal is missing or incorrect. Additionally, the chip senses the output inductor current through the drain- source resistance of the catch MOSFET, shutting off the MOSFET if the inductor curtreverses. The LTC3900 also shuts off the drivers if the supply voltage is low.