- Functions as a frequency counter (DC to 10MHz)
- Four internal gate times: 0.01s, 0.1s, 1s, 10s in frequency counter mode
- Directly drives digits and segments of large multiplexed LED displays (common anode and common cathode versions)
- Single nominal 5V supply required
- Highly stable oscillator, uses 1MHz or 10MHz crystal
- Internally generated decimal points, interdigit blanking, leading zero blanking and overflow indication
- Display off mode turns off display and puts chip into low power mode
- Hold and reset inputs for additional flexibility
- Decimal point and leading zero banking may be externally selected
- Measures period from 0.5µs to 10s
The ICM7216B is a fully integrated Timer Counters with LED display drivers. They combine a high frequency oscillator, a decade timebase counter, an 8-decade data counter and latches, a 7-segment decoder, digit multiplexers and 8- segment and 8-digit drivers which directly drive large multiplexed LED displays. The counter inputs have a maximum frequency of 10MHz in frequency and unit counter modes and 2MHz in the other modes. Both inputs are digital inputs. In many applications, amplification and level shifting will be required to obtain proper digital signals for these inputs.
The ICM7216B can function as a frequency counter, period counter, frequency ratio (fA/fB) counter, time interval counter or as a totalizing counter. The counter uses either a 10MHz or 1MHz quartz crystal timebase. For period and time interval, the 10MHz timebase gives a 0.1µs resolution. In period average and time interval average, the resolution can be in the nanosecond range. In the frequency mode, the user can select accumulation times of 0.01s, 0.1s, 1s and 10s. With a 10s accumulation time, the frequency can be displayed to a resolution of 0.1Hz in the least significant digit. There is 0.2s between measurements in all ranges. The ICM7216D functions as a frequency counter only, as described above.
All versions of the ICM7216 incorporate leading zero blanking. Frequency is displayed in kHz. In the ICM7216B, time is displayed in µs. The display is multiplexed at 500Hz with a 12.2% duty cycle for each digit. The ICM7216B and ICM7216D are designed for common cathode displays with typical peak segment currents of 12mA. In the display off mode, both digit and segment drivers are turned off, enabling the display to be used for other functions.