Features
? Includes IF Amplifier, Quadrature Detector, AF
Preamplifier, and Specific Circuits for AGC, AFC, Tuning Meter, Deviation-Noise Muting, and ON Channel
Detector
? FM IF Amplifier Applications in High-Fidelity,
Automotive, and Communications Receivers
? Exceptional Limiting Sensitivity -12?V (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
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.
The advanced circuit design of the IF system includes desirable deluxe features such as programmable delayed AGC
for the RF tuner, an AFC drive circuit, and an output signal to
drive a tuning meter and/or provide stereo switching logic. In
addition, internal power-supply regulators maintain a nearly
constant current drain over the voltage supply range of
+8.5V to +16V.
The CA3189E is ideal for high-fidelity operation. Distortion in
a CA3189E FM-lF System is primarily a function of the
phase linearity characteristic of the outboard detector coil.
The CA3189E has all the features of the CA3089E plus additions. See CA3189E features compared to the CA3089E in
Table 1.