SCASE18 August 2024 SN74AC165
ADVANCE INFORMATION
The SN74AC165 device is an 8-bit parallel-load shift register that, when clocked, shifts the data toward a serial (QH) output. Parallel-in access to each stage is provided by eight individual direct data (A−H) inputs that are enabled by a low level at the shift/load (SH/LD) input. The SN74AC165 device also features a clock-inhibit (CLK INH) function and a complementary serial ( QH) output.
Clocking is accomplished by a low-to-high transition of the clock (CLK) input while SH/LD is held high and CLK INH is held low. The functions of CLK and CLK INH are interchangeable. Because a low CLK and a low-to-high transition of CLK INH also accomplishes clocking, CLK INH must be changed to the high level only while CLK is high. Parallel loading is inhibited when SH/LD is held high. While SH/LD is low, the parallel inputs to the register are enabled independently of the levels of the CLK, CLK INH, or SER inputs.