SN74LS90N Decade Counter IC DIP-14 5V TTL Logic Binary Counter
The SN74LS90N Decade Counter IC DIP-14 5V TTL Logic Binary Counter is a high-speed integrated circuit from the 74LS TTL logic family. It is designed as a ripple counter capable
Features
- Decade counter (mod-10) and binary counter operation.
- Built-in divide-by-2 and divide-by-5 counter stages.
- TTL compatible 5V operation.
- Asynchronous reset inputs for fast clearing.
Specifications
| Parameter | Value |
|---|---|
| Package | DIP-14 |
| Voltage – Supply | 2V~6V |
| Direction | Up Counter |
| Trigger Type | Falling Edge |
| Operating Temperature | -40℃~+125℃ |
| Reset | Asynchronous |
| Number of Elements | 1 |
| Propagation Delay | 50ns |
| Count Rate | 32MHz;16MHz |
| Features | Reset function |
Pin layout
74LS90 Pin Configuration
| Pin No. | Pin Name | Description |
| 1 | CLKB | Clock Input 2 |
| 2 | R1 | Reset 1 |
| 3 | R2 | Reset 2 |
| 4 | NC | Not Connected |
| 5 | Vcc | Positive Supply Input |
| 6 | R3 | Reset 3 |
| 7 | R4 | Reset 4 |
| 8 | Qc | Output Pin 3 |
| 9 | Qb | Output Pin 2 |
| 10 | Gnd | Ground |
| 11 | Qd | Output Pin 4 |
| 12 | Qa | Output Pin 1 |
| 13 | NC | Not Connected |
| 14 | CLKA | Clock Input 1 |
Footprint
Brief About 7490 IC
74LS90 is basically a MOD-10 decade counter that generate a BCD output code. It consists of four master-slave JK flip-flop, which are internally connected to provide MOD-2 (count to 2) counter and MOD-5 counter. 74LS90 also have an independent toggle JK flip-flop by CLKA and other three are driven by the CLKB.
Internal Logic Diagram
How to Use Decade Counter IC?
The below circuit diagram is for BCD decade counter, by giving HIGH and LOW logic to the CLKA pin, IC start counts from zero to 8 at every HIGH logic. If you want to display the number on a 7-segment display you need a seven segment display driver IC.
Package Include:
1x 7490 IC Decade Counter DIP-14