MOTOROLA MC3363 produced by the U.S. single narrowband VHF FM receiver circuit, mainly used in voice communications and data transmission of wireless receivers. Chip contains a high level transistor, an oscillator, mixer circuit, limiting amplifier, integrator frequency, field strength indicate drive and the carrier frequency detector circuit antenna input to audio output from the secondary conversion of all the full circuit, the same contains a mixer with a local oscillator buffer output, FSK demodulation data slicer comparator. Low supply voltage, low power, high sensitivity and signal to noise ratio, widely used in voice and digital communications receivers. Its main features are as follows: • Wide input frequency band (using the chip of the vibration level of up to 200MHz, using an external oscillator level up to 450MHz) * Built-in high-level radioactive transistor chip * All double-conversion circuit for all * Operating Voltage :2.0 - 6 .0 V
* Low power consumption (at Vcc = 3.0V, typical power consumption of only 3.6mA, except for high level power management)
* Limited sensitivity: 0.3uV (typical, 12dB SINAD, using on-chip high-level radioactive transistor)
* Data Shaping Comparator
* Prepared to receive field strength indicator (RSSI) with a 60dB dynamic range
* A small number of external components
* Use MOTOROLA's "MOSAIC" technology manufacturing
· SO-28 package
MC3363DW narrowband FM receiver circuit works:
Carrier frequency signal from the MC3363's Pin2 input, the high level management within the amplified high frequency output by the Pin4 connection Pin4 LC resonant frequency is a transformer, the center frequency of RF carrier frequency, the coupling to the Pin1 and Pin2 T1 access The first mixer stage. Internal oscillator circuit of the LC with Pin25 and Pin26 to form the first component of the vibration level, and the carrier frequency within RF mixer input signal, the difference frequency 10.7MHz first IF signal is amplified by the Pin23 output by 10.7 ceramic filter pin21 after the election to the internal frequency of the second mixer stage. Internal oscillator circuit and Pin5 and external crystal and capacitor Pin6 form the second level of the vibration frequency of a selected lower than the first IF frequency (ie frequency 455kHz) of 10.245MHz.10.7MHz first IF signal and mixing the second local oscillator frequency, the difference frequency is :10.700-10 .245 = 0.455MHz, ie 455kHz second IF signal.
The second IF signal output from the Pin7 by the selected frequency 455kHz ceramic filter, and then into MC3363 by Pin9 limiting amplifier for high-gain amplifier, a limiting amplifier stage is the main gain stage of the circuit. Pin13 integral component of the external 455kHz LC resonant circuit frequency discriminator, the amplified signal within the second IF frequency discriminator demodulation, and amplified by an audio voltage output of the audio signal from the Pin16.
Pin12 and Pin13 instructions for the field-side driver circuit external components, adjust Pin12 of the 200k resistor to change the field direction drive circuit gain. MC3363 is also equipped with an internal data signal amplification stage, Pin17 as input, Pin18 is output. Waveform data can shaping and amplification. Pin10 and Pin11 place for the second level in the decoupling capacitors.Work to ensure circuit stability.
MC3363DW Typical Application Circuit
