The MV8870 / MV8870-1 is a complete DTMF receiver integrating both the bandsplit filter and digital decoder functions, fabricated in GPS’s double-poly ISO2-CMOS technology. The filter section uses switched capacitor techniques for high and low group filters; the decoder uses digital counting techniques to detect and decode all 16 DTMF tone pairs into a 4-bit code.

External component count is minimised by on-chip provision of a differential input amplifier, clock oscillator and latched 3-state bus interface. The MV8870 and MV8870-1 are functionally identical, but differ in Electrical Characteristics.