Datasheet

ST7538Q Functional description
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Figure 11. CD_PD timing during RX
Figure 12. Receiving path block diagram
T
DCD
T
CD
CD_PD
RAI
D03IN141
8
T
DCD
T
CD
RxD (UART/SPI="1")
demodulation active on RxD pin
RxD (UART/SPI="0")
noise demodulated
noise demodulated
Low Pass Band Pass
PRE-FILTER
IF FILTER
FSK
DEMODULATOR
DIGITAL
FILTER
MIXER
CARRIER/
PREAMBLE
DETECTION
AGC
GAIN
CONTROL
LOCAL
OSC
32
Bit 23
Bits 0 -2
Bits 3-4 &14
Bits 0-2
RAI
Bits 9-10
Bits 12-13 & 22
Carrier Detection
3
RxD
8
CLR/T
1
CD_PD
9
BU
PLL
Bits 3-4
Low Pass
BAND
IN
USE
Bits 3-4 & 22
Band Pass
CHANNEL
FILTER
Band Pass
D03IN1419
HEADER
RECOGN.
Bits 18-21 & 24-47
RXFO
31