tda5225 Infineon Technologies Corporation, tda5225 Datasheet - Page 60

• Manufacturer Part Number: tda5225
• Description: Enhanced Sensitivity Multi-channel Quad-conf Igurat Ion Receiver With Digital Slicer
• Manufacturer: Infineon Technologies Corporation

In case of large frequency steps, an additional VAC routine (VCO Automatic Calibration)
has to be activated when recovering from HOLD Mode (INITPLLHOLD bit). The
maximum allowed frequency step in HOLD Mode without activation of VAC routine is
depending on the selected frequency band. The limits are +/- 1 MHz for the 315 MHz
band, +/- 1.5 MHz for the 434 MHz band and +/- 3 MHz for the 868/915 MHz band.
When this additional VAC routine is enabled, the TDA5225 starts initialization of the
Digital Receiver block after release from HOLD and an additional Channel Hop time.
Figure 39
HOLD Mode is only available in Run Mode Slave. Configuration changes in Self Polling
Mode have to be done by switching to SLEEP Mode and returning to Self Polling Mode
after reconfiguration.
2.6.1.4
The SLEEP Mode is a power save mode. The complete RF part is switched off and the
oscillator is in Low Power Mode. As in HOLD Mode, the chip can be reconfigured. When
switching from SLEEP to Run Mode Slave, the state machine starts with the internal
Start-Up Sequence.
2.6.1.5
In Self Polling Mode TDA5225 autonomously polls for incoming RF wake-up data
streams. At that time there is no processing load on the host microcontroller. When a
wake-up criterion has been found, an interrupt can be generated and the TDA5225 mode
will be changed to Run Mode Self Polling.
A general overview on a typically transmitted protocol and the behaviour of the TDA5225
is given in
Data Sheet
SPI Command
FSM State
Figure
SLEEP Mode
Self Polling Mode (SPM)
Instruction
Data available at Port Pin
Write
0x02
HOLD State Behavior (INITPLLHOLD enabled)
Address
CMC0
40.
HOLD=1
Data
Instruction
Write
0x02
x_CHCFG/
Address
x_PLL..
(sel. other
channel)
Data
60
HOLD
40us
Instruction
Write
0x02
12us @ 2.0MHz
Address
CMC0
HOLD=0
Data
Functional Description
VAC
t
C_ Hop
V1.0, 2010-02-19
VAC
TDA5225
INIT
available at
Port Pin
Data