User's Manual

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design. The product's 26MHz crystal provides the PLL's reference frequency and digital clock, supports
OOK demodulation output with data rate of 1.0-5.0Ksps, and supports time-configurable periodic reset
to avoid crashes caused by various external causes. The CMT2210LH supports two voltage range
operating scenarios, which can be used in 5V system applications or as a 3V system application.
The chip uses LNA + MIXER + IFFILTER + limiter and PLL's low-IF architecture to achieve wireless
reception at frequencies below 1G. The analog front end is responsible for downmixing the RF signal to
the intermediate frequency, and converting the real-time RSSI into an 8-bit digital signal through the
SAR-ADC, and sending it to the internal OOK demodulation and related processing. At the same time,
the internal circuit mixes the intermediate frequency signal to zero frequency (baseband) and performs
a series of filtering and judging processing. At the same time, the AGC dynamic control analog front
end is performed, and finally the original signal is demodulated and output to the off-chip through the
data pin.
Pin Definition
PIN NO. NAME I/O Description
1 GND I
GND
2 RFIN I
RF signal is input to chip LNA
3 VDD5V I
The power input
4 VDDL O
The power output
5 DATA O
Receiving output
6 NC --
Connectionless, suspended
7 NC --
Connectionless, suspended
8 XIN I
Crystal oscillator input, or external reference clock input
Electrical characteristics
VDD = 3.3 V, TOP = 25 ° C, FRF = 433.92 MHz, sensitivity is by receiving a PN9 sequence and matching
to 50 Ω impedance, the BER measurement under the standard of 0.1%.Unless otherwise stated, all results
were tested on the evaluation board cmt2210lh-em.
433MHz-based diffraction performance test filter with high receiving sensitivity, for example, in master-
slave mode communication systems, 433MHz products can actually be used.In this way, the master-slave
topology has the advantages of simple network structure, easy layout, and short power-on time. This is
actually the prototype of the early smart home. 433MHz, 470MHz is now widely used in the smart meter
reading industry.