DF40x is a family of static, master-slave, multiplexed scan D flip-flops. SET is asynchronous and active low. Outputs are buffered and change state on the rising edge of the clock. Logic Symbol DF40x DS C SD SE Q Q Truth Table C D SD SE SN Q QN ↑HX LHHL ↑LXLHLH ↑ XHHHH L ↑X LHHLH XXXXLHL L X X X.