The TP3070V-G/NOPB is a second-generation combined PCM Codec and Filter optimized for digital switching applications on subscriber line and trunk cards. Using advanced switched capacitor techniques, COMBO II combines transmit band pass and receive low pass channel filters with a companding PCM encoder and decoder. The devices are A-law and μ-law selectable and employ a conventional serial PCM interface capable of being clocked up to 4.096MHz. A number of programmable functions may be controlled via a serial control port. Channel gains are programmable over a 25.4dB range in each direction and a programmable filter is included to enable Hybrid Balancing to be adjusted to suit a wide range of loop impedance conditions. Both transformer and active SLIC interface circuits with real or complex termination impedances can be balanced by this filter, with cancellation in excess of 30dB being readily achievable when measured across the pass band against standard test termination networks.
Transmit and receive PCM channel filters
μ-law or A-law companding encoder and decoder
300R Receive power amplifier drives
Hybrid balance cancellation filter
Direct interface to solid-state SLICs
Simplifies transformer SLIC, single winding secondary
