TDA5235
Functional Description
RX
I-Mix
FSK Data
I-
LP
harm sup
digital
FSK Demod
Mix2
CER-
Filter
RX
Input
LNA
IF1
10.7 MHz
RX
ASK Data
ASK /
RSSI
ADC
LP
alias sup
Q-
Mix2
RSSI Generator
Q-Mix
IF
Divider
: N
Attenuation
adjust
Channel Filter
Bandwidth select
1st LO
2nd LO
Figure 5
Double Down Conversion (DDC) with one external filter
For applications which demand very high selectivity and/or channel separation even two
CER filters may be used. Also in applications where one configuration/channel requires
a wider bandwidth than the other (e.g. TPMS and RKE) the second filter can be by-
passed.
RX
FSK Data
I-Mix
I-
LP
harm sup
digital
FSK Demod
Mix2
CER-
Filter
CER-
RX
Input
Filter IF1
10.7 MHz
optional
LNA
IF1
10.7 MHz
RX
ASK Data
ASK /
RSSI
ADC
LP
alias sup
Q-
Mix2
RSSI Generator
Q-Mix
Divider
: N
IF
Attenuation
adjust
Channel Filter
Bandwidth select
1st LO
2nd LO
Figure 6
Double Down Conversion (DDC) with two external filters
Data Sheet
21
V1.0, 2010-02-19
INFINEON [ Infineon ]
