Practical and Theoretical Design Cosiderations for Bridge Negative Feedback Amplifiers in Carrier Telephony

The problem of providing proper impedance matching for interconnecting circuitry in Carrier Telephony Systems is of first-order importance. Transmission branches that contain nonpassive elements, such as amplifiers, are of particular concern and thus require special treatment. Bridge feedback amplifiers employing a hybrid output transformer offer outstanding advantages as a solution. Basic design formulae and a practical example with measured results are presented for such an amplifier.