74HC163 Pinout
74HC163 4-bit Binary Counter · 4-bit synchronous binary counter with SYNCHRONOUS clear — same pinout as the 74HC161.
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | SR · /SR | Control | Synchronous reset / clear (active-low, on clock edge) |
| 2 | CP · CLK | Control | Clock (counts on rising edge) |
| 3 | D0 | Input | Parallel data input 0 (LSB) |
| 4 | D1 | Input | Parallel data input 1 |
| 5 | D2 | Input | Parallel data input 2 |
| 6 | D3 | Input | Parallel data input 3 (MSB) |
| 7 | CEP · ENP | Control | Count enable P |
| 8 | GND | GND | Ground |
| 9 | PE · /PE | Control | Parallel-load enable (synchronous, active-low) |
| 10 | CET · ENT | Control | Count enable T (also gates TC) |
| 11 | Q3 | Output | Count output 3 (MSB) |
| 12 | Q2 | Output | Count output 2 |
| 13 | Q1 | Output | Count output 1 |
| 14 | Q0 | Output | Count output 0 (LSB) |
| 15 | TC · RCO | Output | Terminal count / ripple carry out (high at 15) |
| 16 | VCC | Power | Supply + (2–6V) |
How to read the 74HC163 pinout
- 01
Find pin 1
One end of the chip has a half-circle notch or a dot; with the notch facing up, the top-left pin is pin 1.
- 02
Count counter-clockwise
Count counter-clockwise from pin 1: go down the left side first, then up the right side from the bottom.
- 03
Check the table below
Look up each pin's function by number in the table below; power/ground are color-coded, and alternate-function signals are in parentheses.
Frequently asked questions
What is the difference between 74HC161 and 74HC163?
Same pinout and 4-bit binary counting. The 74HC161 clears ASYNCHRONOUSLY (the moment /MR goes low); the 74HC163 clears SYNCHRONOUSLY (on the next clock edge), which avoids the brief decode glitch.
Which should I use for a clean modulo-N counter?
The 74HC163 — its synchronous clear lets you reset exactly on the clock edge with no runt pulse, making glitch-free mod-N dividers easier.
Pinout data comes from NXP/TI 74HC163 datasheet (standard DIP-16 numbering). Refer to the actual device datasheet as authoritative for the pinout.