HEF4511B

The HEF4511B is a BCD to 7-segment latch/decoder/driver with four address inputs (D_A to D_D), an active LOW latch enable input (EL), an active LOW ripple blanking input (BI), an active LOW lamp test input (LT), and seven active HIGH n-p-n bipolar transistor segment outputs (O_a to O_g).

When EL is LOW, the state of the segment outputs (O_a to _Og) is determined by the data on D_A to D_D. When EL goes HIGH, the last data present on D_A to D_D are stored in the latches and the segment outputs remain stable. When LT is LOW, all the segment outputs are HIGH independent of all other input conditions of HEF4511B. With LT HIGH, a LOW on BI forces all segment outputs LOW. The inputs LT and BI do not affect the latch circuit.