Monolithic Circuits for Radio Receivers

This paper describes an AM Broadcast Receiver utilizing two monolithic bi-polar chips containing all the active and many of the passive devices. Design goals such as minimizing the external components and meeting the performance requirements of a complete line of AM radio receivers, from personal portable through table model, have been achieved by using many devices and the characteristics inherent in monolithic circuits. The integrated circuit chips, containing 28 transistors and 53 resistors, are capable of 142 dB gain and 250 mW of audio output. Circuitry to provide good overload performance, lumped I.F. selectivity, d.c. coupled audio with push-pull output, and options for tuned R.F. and Class A drive for larger power output are discussed.