TDA5230 Datasheet, PDF (60/186 Pages) Infineon Technologies AG – Universal Low Power ASK/FSK Single Conversion Multi-Channel Image-Reject Receiver

TDA523x
Functional Description
2) Calculation of usable Wake Up Pattern Time:
The Wake Up Pattern time is the minimal duration of wake up patterns.
T_{Wakeup_PatternA}=Wake Up Pattern/(Data Rate*tolerance)=2000/(10 kb/s*1.1)=181.81 ms
T_{Wakeup_PatternB}=2000/(10 kb/s*1.1)=363.62ms
T_{usable_Wakeup_PatternA}=T_{Wakeup_PatternA}-T_{WakeUp_ConfigAChannel1}=181.81ms-2.55ms=179.26 ms
T_{usable_Wakeup_PatternB}=T_{Wakeup_PatternB}-T_{WakeUp_ConfigBChannel1}=363.62ms-3.98ms=359.64 ms
3) Calculation of the Master Period
T_MasterPeriod is smaller then T_{usable_Wakeup_PatternA} or T_{usable_Wakeup_PatternB} whichever is
shorter. In our example:
T_MasterPeriod<T_{usable_Wakeup_PatternA}=179.26 ms
Calculation of the On Time
In Fast Fall Back to Sleep Wake Up Mode, the On Time limits the search for a Wake Up
Criteria for all used channels in both configurations. Therefore the On Time is the sum
of On Time for all used channels and configurations.
T_{ON_}>T_{WakeUp_ConfigAChannel1..3}+T_{WakeUp_ConfigBChannel1..2}=2.55 ms+2.02 ms+2.02 ms+
+3.98 ms +3.98 ms =14.55 ms
Note: Different to Constant On/Off Time, a longer On Time as calculated will typically not
increase power consumption.
Calculation of the Off Time
The Off Time is the Master Period minus the On Time.
T_OFF=T_MasterPeriod-T_ON=179.26 ms-14.55 ms=164.71 ms
Note: Use the TDA523x IAF Configuration Tool to translate the calculated values into
register settings. Enter On and Off Time as calculated. Watch the Master Period and
vary Off Time till the resulting Master Period is shorter than the result of the calculation.
Take care that T_ON must be always longer and T_MasterPeriod always shorter than the
calculated values!
2.4.6.4 Mixed Mode (Constant On/Off Time & Fast Fall Back to Sleep)
This mode combines Constant On/Off Time for Configuration A and Fast Fall Back to
Sleep for Configuration B. The next figure shows the same scenarios as seen earlier, but
now for Mixed Mode.
Data Sheet
56
Version 4.0, 2007-06-01