2 layers69 × 28.5 mm

GR DTMF Decoder
GadgetReboot/DTMF_Decoder
MT8870 DTMF decoder for POTS phone line interfacing
15 parts9
Boards in 2 GitHub repositories, designed in KiCad, that use the MT8870DS1 by Microchip Technology (-40℃~+85℃ 15mW 4.75V~5.25V 9mA SOIC-18-300mil Telecom Interface ICs ROHS). See how each wires it, with its parts, size, README and files; the MT8870DS1’s symbol, footprint and pinout are on its own page.

GadgetReboot/DTMF_Decoder
MT8870 DTMF decoder for POTS phone line interfacing
