MH88632B

® MH88632B Central Office Interface Circuit Preliminary Information Features Supports Loop Start and Ground Start protocols 2-4 Wire conversion Programmable Input Impedance, Network Balance Impedance and gains Three relay drivers Line state detection outputs 15mA operation allowing long line length capability On-hook reception for Caller Line Identification Meets FCC Part 68 Leakage Current Requirements ISSUE 3 September 1997 Ordering Information MH88632B 40 Pin SIL Package MH88632BT 40 Pin 90˚ Package 0°C to 70°C Description The Mitel MH88632B Central Office Interface Circuit provides a complete analog and signalling link between audio switching equipment and a subscriber line. The device is available in a single in line package for high packing densities or in a 90˚ package for reduced card clearance. The device is fabricated using thick film hybrid technology for optimum circuit design and very high reliability. Applications Interface to Central Office telephone line for PBX Key Telephone System Terminal Equipment Digital Loop Carrier Wireless Local Loop RV FL RL RG TG VCC VEE AGND GRD GRC BRD BRC LRD LRC Status Detection VRLY Relay Driver Circuit RGND RING Line Termination 2-4 Wire Hybrid Receive Gain Dummy Ringer RX GRX1 GRX0 Transmit Gain TIP Network Balance TX GTX1 GTX0 Impedance Matching XLA XLB XLC XLD Z1 Z2 Z600 Z900 NS N1 N2 NATT Figure 1 - Functional Block Diagram 2-239 MH88632B Preliminary Information TIP RING XLA...