The HT9172 is a Dual Tone Multi Frequency (DTMF) receiver device which includes an integrated digital decoder and band split filter functions as well as
power-down and inhibit mode operations. The device
uses digital counting techniques to detect and decode
the full range of 16 DTMF tone pairs into a 4-bit code
output. Highly accurate switched capacitor filters are utilised to divide the DTMF dual tone frequencies into low
and high group signals. An integrated dial tone rejection
circuit is provided to eliminate the need for pre-filtering.
Features of HT9172 DTMF Receiver
- Operating voltage: 2.5V~5.5V
- Minimal external component requirements
- No external filter required
- Low standby current in power down mode)
- Excellent performance
- Tristate data output for MCU interface
- 3.58MHz crystal or ceramic resonator oscillator
- 1633Hz can be inhibited by the INH pin
- 18-pin DIP/SOP packaging
