U3500BM

U3500BM Cordless Telephone Signal Processor Description The programmable cordless phone signal processor includes all necessary low frequency parts such as microphone- and earphone amplifier, compander, preemphasis, deemphasis, scrambler, data management, power-supply management, as well as RF receiving parts such as IF converter, FM demodulator. RSSI and low noise amplifier. Several gains and mutes in transmit and receive direction are controlled by serial bus while compander, pre- and deemphasis and scrambler can be bypassed. Features RF Receiver Part D Low-noise amplifier D IF converter D FM demodulator D RSSI D Compander D Pre- and deemphasis D Scrambler D Data management D Power-supply management D Serial bus Low Frequency Part D Symmetrical input of microphone amplifier D Symmetrical output of earpiece amplifier Application: CT0 Block Diagram MIXO IFIN1 IFIN2 DACO www.DataSheet4U.com IFAMP MIXIN MIXGND Scrambler frequency LOIN Oscillator 11.15 MHz Divider RECO2 D/A LNAIN RGND LNAO VBATT MIC LNA LPF REC RECO1 MIC1 MIC2 MICO RXDAT Battery low detector C D Serial Bus LPF LPF TGAIN ADJ.2 Limiter Preem TGAIN ADJ.1 Compressor COIN TXDAT ETC Expander EXIN LOG Demodulator RGAIN ADJ LPF LPF Deem RXO Scrambler frequency VCC TXO GND CTC 14678 Figure 1. Block diagram Rev. A3, 20-May-98 1 (17) Preliminary Information U3500BM Pin Description TXO CTC COIN MICO MIC2 MIC1 GND RXO RECO2 1 2 3 4 5 6 7 8 9 28 TXDAT 27 RXDAT 26 D 25 C 6 24 DACO 23 VCC 22 LOIN 21 VBATT 20 LNA...