View ds2153q datasheet:

DS2153Q E1 Single-Chip Transceiver www.dalsemi.com FEATURES PIN ASSIGNMENT Complete E1(CEPT) PCM-30/ISDN-PRI FUNCTIONAL BLOCKS transceiver functionality Onboard line interface for clock/data recovery and waveshaping 32-bit or 128-bit jitter attenuator Generates line build-outs for both 120-ohm and 75-ohm lines Frames to FAS, CAS, and CRC4 formats Dual onboard two-frame elastic store slip buffers that can connect to backplanes up to PARALLEL CONTROL 8.192 MHz PORT 8-bit parallel control port that can be used on either multiplexed or non-multiplexed buses Extracts and inserts CAS signaling DALLAS Detects and generates Remote and AIS alarms DS2153Q ACTUAL SIZE OF 44-PIN PLCC E1 SCT Programmable output clocks for Fractional E1, H0, and H12 applications Ful