HM9270D
Description
The HM 9270C/D is a plete DTMF receiver integrating both the bandsplit filter and digital decoder functions. The filter section uses switched capacitor techniques for high- and low-group filters and dial-tone rejection. Digital counting techniques are employed in the decoder to detect and decode all 16 DTMF tonepairs into a 4-bit code. External ponent count is minimized by on-chip provision of a differential input amplifier, clock-oscillator and latched 3-state bus interface.
Features
- -
- -
- -
- - plete receiver in an 18-pin package. Excellent performance. CMOS, single 5 volt operation. Minimum board area. Central office quality. Low power consumption. Power-Down mode (HM9270D only). Inhibit-mode (HM9270D only).
Pin Configurations
HM9270C
IN+ IN GS 1 2 3 4 5 6 7 8 9 18 17 16 15 14 13 12 11 10 VDD St/GT ESt St D Q4 Q3 Q2 Q1 TOE IN+ IN GS
1 2 3 4 5 6 7 8 9 18 17 16 15 14 13 12 11 10 VDD St/GT ESt St D Q4 Q3 Q2 Q1 TOE
VREF IC- IC- OSC1 OSC2 VSS
VREF INH PWDN...
