DESCRIPTION

The HEF4534B is a 5-decade ripple counter. The binary outputs of the decade counters are time-multiplexed by an internal scanner on four BCD outputs (O0 to O3). The selected decade is indicated by a logic HIGH on the appropriate digit select output (OS0: units, 1; OS1: tens,

10; OS2: hundreds, 102;OS3: thousands, 103; OS4: ten thousands, 104).

The binary outputs (O0to O3) and the select outputs (OS0 to OS4) are 3-state controlled via enable inputs EO andEOS respectively, allowing interface with other bus orientated devices. Cascading may be accomplished by using the carry out (TC). The counter is triggered by a LOW to HIGH transition on the decade clock (CPA) and is reset by a HIGH level on the master reset (MR).