The 7490 is a 14-pin decade counter IC with four master-slave flip-flops arranged as a divide-by-two counter and a divide-by-five counter. Together they count 0 to 9 in BCD. It has gated reset-to-zero and set-to-nine inputs, a 42 MHz count frequency and typical power dissipation of 145 mW.
Key Features
- Divide-by-2 and divide-by-5 sections combine for decade counting
- Four master-slave flip-flops
- Gated zero reset
- Gated set-to-nine inputs for BCD nine's complement use
- 42 MHz count frequency
- 145 mW typical power dissipation
Specifications
| Part number | 7490 |
|---|---|
| Function | Decade counter |
| Pins | 14 |
| Count frequency | 42 MHz |
| Power dissipation | 145 mW (typ) |
| SKU | 107490 |
What's Included
- 1 x 7490 IC
Ideal For
Digital clocks, event counters and classroom counting circuits with 7-segment displays.
Frequently Asked Questions
How do I make it count to 10?
Connect the divide-by-2 output to the divide-by-5 clock input; the four outputs then count 0 to 9 in BCD.
Can it drive a display directly?
Not usually; pair it with a BCD-to-7-segment decoder.