TDA5240 Datasheet, PDF (107/284 Pages) Infineon Technologies AG – Enhanced Sensitivity Multi-Channel Quad-Configuration Receiver

TDA5240
Functional Description
After an EOM was found, the information about the RF channel and the configuration of
the actual payload data is saved in the RFPLLACC register.
After detection of EOM the TDA5240 can either proceed with a search for a wake-up
criterion in the next configuration or a search for wake-up in Configuration A can follow
or the TOTIMs of the current configuration are reloaded for being prepared to receive
another (redundant) payload data frame within the same configuration.
Alternatively, a transparent data stream can also be processed externally by the
Application Controller. Therefore the external controller needs the possibility to send
following commands, which would normally be generated by the TDA5240 itself (see
Figure 77 and EXTPCMD register as well):
• EXTTOTIM: So the TDA5240 can proceed with Self Polling Mode (either with the
next programmed channel or with Configuration A).
• EXTEOM found: In this case the TDA5240 can either proceed with Self Polling Mode
(either with the next configuration or with Configuration A) or stay in Run Mode Self
Polling.
EXTTOTIM and EXTEOM are only available, when the external processing mode is
deactivating functional blocks (see bit group x_CHCFG.EXTPROC).
When the actual processed configuration is right before the Off time and the Application
Controller sends one of the above mentioned commands, then the TDA5240 can
proceed with the Off time (in case next configuration is selected).
If the autonomous Wake-up Search with Configuration A follows a TOTIM or EOM event,
then also the Polling Timer is initialized, this means a new On period is started. In case
the Wake-up Search is started with Next Programmed Channel (after a TOTIM event) or
Wake-up Search gets started with Next Configuration (after an EOM event), then the
Polling Timer is not initialized. This means that the On time counter proceeds with the
old value from leaving the previous Wake-up search period successfully. This is the case
for Fast Fall Back to SLEEP Mode.
In Constant On-Off Time Mode the Polling Timer is always initialized after a TOTIM or
EOM event.
Data Sheet
107
V4.0, 2010-02-19