HT9170B/HT9170D -- DTMF Receiver General Description 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 上海辰祥電子科技有限公司 聯(lián)系人：周平 13917885749