Description:
The 74HC161 are presettable synchronous counters that feature look-ahead carry logic for use in high-speed counting applications. The ’HC161 and ’HCT161 are asynchronous reset decade and binary counters, respectively. Counting and parallel presetting are both accomplished synchronously with the negative-to-positive transition of the clock.
A low level on the synchronous parallel enable input, SPE, disables counting operation and allows data at the P0 to P3 inputs to be loaded into the counter (provided that the setup and hold requirements for SPE are met).
All counters are reset with a low level on the Master Reset input, MR. In the HC163 counters (synchronous reset types), the requirements for setup and hold time with respect to the clock must be met.
Two count enables, PE and TE, in each counter are provided for n-bit cascading. In all counters reset action occurs regardless of the level of the SPE\, PE and TE inputs (and the clock input, CP, in the HC161).
If a decade counter is preset to an illegal state or assumes an illegal state when power is applied, it will return to the normal sequence in one count as shown in state diagram.
The look-ahead carry feature simplifies serial cascading of the counters. Both count enable inputs (PE and TE) must be high to count. The TE input is gated with the Q outputs of all four stages so that at the maximum count the terminal count (TC) output goes high for one clock period. This TC pulse is used to enable the next cascaded stage.
Included:
M74HC161B1R (CD74HC161) (74HC161)
This item features:
- HC161 4-Bit Binary Counter, Asynchronous Reset
- Synchronous Counting and Loading
- Two Count Enable Inputs for n-Bit Cascading
- Look-Ahead Carry for High-Speed Counting
-
- Standard Outputs...10 LSTTL Loads
- Bus Driver Outputs...15 LSTTL Loads
- Wide Operating Temperature Range . . . -55°C to 125°C
- Balanced Propagation Delay and Transition Times
- Significant Power Reduction Compared to LSTTL Logic ICs
- CMOS Input Compatibility, Il less than or equal 1µA at VOL, VOH
- HC Types
- 2V to 6V Operation
- High Noise Immunity: NIL = 30%, NIH = 30% of VCC at VCC = 5V
- Fanout (Over Temperature Range)
Condition:
- New and Authentic Component(s) - M74HC161B1R High Speed CMOS Logic 4-Bit Binary Counter with Asynchronous Reset ICs.
- Friendly Note: Be mindful of the many, inexpensive, counterfeits available on the market.
General details:
- We are expanding on a daily basis. If you do not see the part, or quantity of the part, you are looking for, please, let us know. We will do our best to accommodate you.