DESCRIPTION
The circuit have four fundamental modes of operation, in order of preference: synchronous reset, parallel load, count-up and hold. Four PIN CONNECTION AND IEC LOGIC SYMBOLS control inputs, Master Reset (CLEAR), Parallel Enable Input (LOAD), Count Enable Input (PE) and Count Enable Carry Input (TE), determine the mode of operation as shown in the Truth Table. A LOW signal on CLEAR overrides counting and parallel loading and allows all outputs to go LOW on the next rising edge of CLOCK. A LOW signal on LOAD overrides counting and allows information on Parallel Data Qn inputs to be loaded into the flip-flops on the next rising edge of CLOCK. With LOAD and CLEAR, PE and TE permit counting when both are high. Conversely, a LOW signal on either PE and TE inhibits counting. All inputs and outputs are equipped with protection circuits against static discharge, giving them 2KV ESD immunity and transient excess voltage. July 2001 1/13 74LVQ163 INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN...
STMicroelectronics
