MH89726 Datasheet | Mitel Networks

Features - - - - - - Operates from single or dual power supply MH89726 extends transmission performance for the MT8972 (DNIC) at 160kbit/s line rate MH89728 extends transmission performance for the MT8972 (DNIC) at 80kbit/s line rate MH89726 and MH89728 are pin for pin patible with each other pact SIL package Over 6km loop range on 24 AWG ISSUE 2 November 1990 Ordering Information MH89726/728 10 Pin SIL Package 0°C to 70°C Description The MH89728 and MH89726 are thick film hybrid devices which may be used to extend the operating range of the MT8972 (DNIC). The hybrids bine signal equalization and amplification for the receive and transmit paths on each device. The small size of these hybrids makes them suitable for line card or terminal use with the MT8972. The gain of the transmit signal may be adjusted through the use of an external resistor. Applications - - - - Digital subscriber lines Digital PABX line cards and telephone sets High speed, limited distance modem ISDN U - Interface TXGAIN TXIN Pre Equalizer TX Amplifier TXOUT Phase pensator RXOUT Pre Canceller RX Amplifier RXIN RXIN + VBias TEST V+ V- Figure 1 - Functional Block Diagram 9-127 MH89726/728 Advance Information TXGAIN TXOUT RXIN + RXIN VVBias V+ TEST RXOUT TXIN 1 2 3 4 5 6 7 8 9 10 Figure 2 - Pin Connections Pin Description Pin # 1 Pin Name TXGAIN Description Transmit Gain. To be connected to Pin 2. An increase in gain can be achieved by connecting an external resistor REXT between Pin 1 and Pin 2. The resultant gain is calculated using; A= (R/24) + 2.8, where A=Gain and R= REXT (kΩ). Transmit Output. Connect to the termination network. Negative Receive Signal. Connect to TXOUT, Pin 2. Positive Receive Signal. Connected to line transformer. Negative power supply. Internal Bias Voltage. Connect to GND through 0.33 µF for single power supplies. Connect to GND directly for split power supplies. Positive power supply. Test. Used for production testing. Leave unconnected. Receive...