Description The Harris CA3189E is a monolithic integrated circuit that provides all the functions of a comprehensive FM-lF system. The block diagram of the CA3189E includes a three-stage FM-lF amplifier/limiter configuration with level detectors for each stage, a doubly-balanced quadrature FM detector and an audio amplifier that features the optional use of a muting (squelch) circuit Features • Includes IF Amplifier, Quadrature Detector, AF Preamplifier, and Specific Circuits for AGC, AFC, Tun ing Meter, Deviation-Noise Muting, and ON Channel Detector • FM IF Amplifier Applications in High-Fidelity, Automotive, and Communications Receivers • Exceptional Limiting Sensitivity -12µV (Typ) at -3dB Point • Low Distortion -0.1% (Typ) (with Double-Tuned Coil) • Single-Coil Tuning Capability • Improved S + N/N Ratio • Externally Programmable Recovered Audio Level • Provides Specific Signal for Control of Interchannel Muting (Squelch) • Provides Specific Signal for Direct Drive of a Tuning Meter • On Channel Step for Search Control • Provides Programmable AGC Voltage for RF Amplifier • Provides a Specific Circuit for Flexible Audio Output • Internal Supply Voltage Regulators • Externally Programmable “On” Channel Step Width, and Deviation at Which Muting Occurs
|