These devices are designed to perform the transmit encoding (A/D conversion) and receive decoding (D/A conversion) as well as the transmit and receive filtering functions in a PCM system. They are intended to be used at the analog termination of a PCM line or trunk. The devices require two transmit and receive master clocks that may be asynchronous (1.536 MHz, 1.544 MHz, or 2.048 MHz), transmit and receive data clocks that are synchronous with the master clock (but can vary from 64 kHz to 2.048 MHz), and transmit and receive frame-sync pulses. The TP3054B, TP3057B, TP13054B, and TP13057B provide the band-pass filtering of the analog signals prior to encoding and after decoding of voice and call progress tones. The TP3054B and TP13054B contain patented circuitry to achieve low transmit channel idle noise and are not recommended for applications in which the composite signals on the transmit side are below 55 dBm0. The TP3054B and TP3057B are characterized for operation from 0C to 70C. The TP13054B and TP13057B are characterized for operation from 40C to 85C. These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the CMOS gates.