The CAMD CM8888/8888-2 is a fully integrated DTMF Transceiver, featuring adjustable guard time, automatic tone burst mode, call progress mode, and a fully compatible 8051, 8086/8 microprocessor interface. The CM8888/8888-2 is manufactured using state-of-the-art advanced CMOS technology for low power consumption and precise data handling. The CM8888/8888-2 is based on the industry standard CM8870 DTMF Receiver, while the transmitter utilizes a switchedcapacitor D/A converter for low distortion, highly accurate DTMF signaling. Internal counters provide an automatic tone burst mode which allows tone bursts to be transmitted with precise timing. A call progress filter can be selected by an external microprocessor for analyzing call progress tones. The CM8888-2 is electrically equivalent to the CM8888 but does not include the call progress function. Block Diagram