ASTEC AS3843
The AS3842 family of control ICs provide pin-for-pin replacement of the industry standard UC3842 series of devices. The devices are redesigned to provide significantly improved tolerances in power supply manufacturing. The 2.5 V reference has been trimmed to 1.0% tolerance.FEATURES
¥ 2.5 V bandgap reference trimmed to 1.0% and temperature-compensated ¥ Standard temperature range extended to 105¡C ¥ AS3842/3 oscillations trimmed for precision duty cycle clamp ¥ AS3844/5 have exact 50% max duty cycle clamp ¥ Advanced oscillator design simplifies synchronization ¥ Improved specs on UVLO and hysteresis provide more predictable start-up and shutdown ¥ Improved 5 V regulator provides better AC noise immunity ¥ Guaranteed performance with current sense pulled below groundDESCRIPTION
The oscillator discharge current is trimmed to provide guaranteed duty cycle clamping rather than specified discharge current. The circuit is more complet