JAJS124Q December 1999 – October 2019 UCC1895 , UCC2895 , UCC3895
PRODUCTION DATA.
DELAB programs the dead time between switching of OUTA and OUTB. DELCD programs the dead time between OUTC and OUTD. This delay is introduced between complementary outputs in the same leg of the external bridge. The UCC3895 allows the user to select the delay, in which the resonant switching of the external power stages takes place. Separate delays are provided for the two half-bridges to accommodate differences in resonant-capacitor charging currents. The delay in each stage is set according to Equation 3.
where
DELAB and DELCD source about 1-mA maximum. Choose the delay resistors so that this maximum is not exceeded. Programmable output delay is defeated by tying DELAB and, or, DELCD to REF. For an optimum performance keep stray capacitance on these pins at less than 10 pF.