Communication ICs PCM codec IC for digital cellular telephones BU8733KV The BU8733KV is a PCM codec IC developed for use with digital cellular telephones. The BU8733KV contains analog input / output features such as a 14-bit linear precision, µ / A-LAW codec, mic and speaker amplifiers, and a switching transistor for the ringer drive. Also, there is a built-in DSP interface circuit for support of multiple DSP formats making this IC perfect for use with PDC cellular telephones. Applications Digital cellular telephones Features 1) 3V single power supply (VDD = 2.7V to 3.3V). 2) Built-in 14-bit precision linear, µ / A-LAW codec. 3) Transmission filter for the codec unit conforms to ITU-T recommendations. 4) Built-in PLL circuit for system clock generation. 5) Tone signal generator contains DTMF signal, scale tone, and variable tone functions. 6) Analog input / output functions: Built-in mic amplifier. Built-in receiver speaker amplifier (32Ω BTL type). Built-in attenuator for wide gain adjustment range. Data signal I / O circuit allows for connection to external devices. For the external output and receiver output, softmute function reduces pop noise when the power is turned on and off. 7) Internal switching transistor for ringer drive. 8) Internal DSP interface circuit supports multiple DSP formats. Absolute maximum ratings (Ta = 25C) 599 Communication ICs Recommended operating conditions (Ta = 25C) Block diagram 600 BU8733KV Communication ICs BU8733KV Pin descriptions 601 Communication ICs 602 BU8733KV Communication ICs BU8733KV Electrical characteristics(unless otherwise noted, Ta = 25C, DVDD = RXVDD = TXVDD = 3.0V, FSYNC = 8kHz, gain of each attenuator = 0dB) 603 Communication ICs 604 BU8733KV Communication ICs BU8733KV 605 Communication ICs Digital AC characteristics 606 BU8733KV Communication ICs BU8733KV Measurement circuit 607 Communication ICs Application example 608 BU8733KV Communication ICs BU8733KV External dimensions (Units: mm) 609