LT1776 UUUPIN FUNCTIONS 10% and 90% duty cycle. The sync function is internally abnormally low, e.g., 2/3 of normal or less. This feature disabled if the FB pin voltage is low enough to cause helps maintain proper short-circuit protection. oscillator slowdown. If unused, this pin should be grounded. VC (Pin 8): This is the control voltage pin which is the FB (Pin 7): This is the inverting input to the feedback output of the feedback amplifier and the input of the amplifier. The noninverting input of this amplifier is inter- current comparator. Frequency compensation of the over- nally tied to the 1.24V reference. This pin also slows down all loop is effected by placing a capacitor, (or in most cases the frequency of the internal oscillator when its voltage is a series RC combination) between this node and ground. WBLOCK DIAGRA VCC 2 5 VIN R1 RSENSE VBG SHDN 1 BIAS VB I Q3 SWDR COMP Q4 Q2 SWDR SWON SYNC 6 OSC LOGIC Q1 BOOST SWOFF 3 VSW D1 GND 4 SWON I BOOST COMP I I VC 8 FB VTH BOOST AMP FB 7 SWOFF gm I Q5 VBG 1776 BD 6