LM567/LM567C Tone Decoder
February 2003
LM567/LM567C
Tone Decoder
General Description
The LM567 and LM567C are general purpose tone decoders
designed to provide a saturated transistor switch to ground
when an input signal is present within the passband. The
circuit consists of an I and Q detector driven by a voltage
controlled oscillator which determines the center frequency
of the decoder. External components are used to indepen-
dently set center frequency, bandwidth and output delay.
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High rejection of out of band signals and noise
Immunity to false signals
Highly stable center frequency
Center frequency adjustable from 0.01 Hz to 500 kHz
Applications
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Touch tone decoding
Precision oscillator
Frequency monitoring and control
Wide band FSK demodulation
Ultrasonic controls
Carrier current remote controls
Communications paging decoders
Features
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20 to 1 frequency range with an external resistor
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Logic compatible output with 100 mA current sinking
capability
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Bandwidth adjustable from 0 to 14%
Connection Diagrams
Metal Can Package
Dual-In-Line and Small Outline Packages
00697501
Top View
Order Number LM567H or LM567CH
See NS Package Number H08C
00697502
Top View
Order Number LM567CM
See NS Package Number M08A
Order Number LM567CN
See NS Package Number N08E
© 2004 National Semiconductor Corporation
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