The HT9170B/D are Dual Tone Multi Frequency (DTMF) receivers integrated with digital decoder and bandsplit filter functions as well as power-down mode and inhibit mode operations. Such devices use digital counting techniques to detect and decode all the 16 DTMF tone pairs into a 4-bit code output.
Highly accurate switched capacitor filters are implemented to divide tone signals into low and high group signals. A built-in dial tone rejection circuit is provided to eliminate the need for pre-filtering.
Features
– Operating voltage: 2.5V~5.5V
– Minimal external components
– No external filter is required
– Low standby current (on power down mode)
– Excellent performance
– Tristate data output for MCU interface
– 3.58MHz crystal or ceramic resonator
– 1633Hz can be inhibited by the INH pin
– HT9170B: 18-pin DIP package
HT9170D: 18-pin SOP package
