TC170

1 TC170 CMOS CURRENT MODE PWM CONTROLLER FEATURES s s s s s s s s s s s s s s s Low Supply Current With CMOS Technology ................................. 3.8mA Max Internal Reference ............................................. 5.1V Fast Rise/Fall Times (CL = 1000pF) ............. 50nsec Dual Push-Pull Outputs Direct-Power MOSFET Drive High Totem-Pole Output Drive .................... 300mA Differential Current-Sense Amplifier Programmable Current Limit Soft-Start Operation Double-Pulse Suppression Undervoltage Lockout Wide Supply Voltage Operation ............... 8V to16V High Frequency Operation .......................... 200kHz Available with Low OFF State Outputs Low Power, Pin-Compatible Replacement for UC3846 GENERAL DESCRIPTION The TC170 brings low-power CMOS technology to the current-mode-switching power supply controller market. Maximum supply current is 3.8 mA. Bipolar current-mode control integrated circuits require five times more operating current. The dual totem-pole CMOS outputs drive power MOSFETs or bipolar transistors. The 50nsec typical output rise and fall times (1000pF capacitive loads) minimize MOSFET power dissipation. Output peak current is 300mA. The TC170 contains a full array of system-protection circuits (see features). Current-mode control lets users parallel power supply modules. Two or more TC170 controllers can be slaved together for parallel operation. Circuits can operate from a master TC170 internal oscillator or an external system oscilla...