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).