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www.fairchildsemi.com
Features
Wide frequency range – 0.01 Hz to 300 kHz
Wide supply voltage range – 4.5V to 20V
DTL/TTL/ECL logic compatibility
FSK demodulation with carrier-detector
Wide dynamic range – 2 mV to 3 V
RMS
Adjustable tracking range –
±
1% to
±
80%
Excellent temperature stability – 20 ppm/
°
C typical
Applications
FSK demodulation
Data synchronization
Tone decoding
FM detection
Carrier detection
Description
The RC2211A is a monolithic phase-locked loop (PLL)
system especially designed for data communications. It is
particularly well-suited for FSK modem applications, and
operates over a wide frequency range of 0.01 Hz to 300 kHz.
It can accommodate analog signals between 2 mV and 3V,
and can interface with conventional DTL, TTL and ECL
logic families. The circuit consists of a basic PLL for
tracking an input signal frequency within the passband, a
quadrature phase detector which provides carrier detection,
and an FSK voltage comparator which provides FSK
demodulation. External components are used to indepen-
dently set carrier frequency, bandwidth and output delay.
Block Diagram
65-2211-01
f
-Detector
Loop Filter
VCO
f
f
FSK
Input
Preamp
Data Filter
FSK
Data
Output
FSK
Comparator
Lock
Detector
Outputs
Lock
Detector
Comparator
Lock
Detector
Filter
f
-Detector
RC2211A
FS K Demodulator/Tone Dec oder
Rev. 1.3.1