tda5251f1 Infineon Technologies Corporation, tda5251f1 Datasheet - Page 66

• Manufacturer Part Number: tda5251f1
• Description: Ask/fsk 315mhz Wireless Transceiver
• Manufacturer: Infineon Technologies Corporation

Confidential
Timing for data detection looks like the following. Two settings are possible: „Continuous“ and
„Single Shot“, which can be set by D5 and D6 in register 00H.
Figure 3-29
Note 1: Chip internal signal „Sequencer enables data detection“ has a LOW to HIGH transition
about 2.6ms after RX is activated (see Figure 2-15).
Note 2: The positive edge of the „Window Count Complete“ signal latches the result of comparison
of the analog to digital converted RSSI voltage with TH3 (register 08H). A logic combination of this
output and the result of the comparison with single/double TH x defines the internal signal
„data_valid“.
Figure 3-29 shows that the logic is ready for the next conversion after 3 periods of the data signal.
Timing in Single Shot mode can be seen in the subsequent figure:
Figure 3-30
Preliminary Specification
Frequency Detection timing in continuous mode
Frequency Detection timing in Single Shot mode
Compare with double
(Frequency) Window
Compare with single
Sequenzer enables
TH and latch result
TH and latch result
Compare with double
(Frequency) Window
Compare with single
Sequenzer enables
TH and latch result
TH and latch result
Count Complete
Counter Reset
data detection
Count Complete
Counter Reset
data detection
Gate time
Gate time
Data
start o f con version
Data
start of co nve rsio n
rese t
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no po ssible s ta rt of n ext c onve rs io n
c oun t
b eca use of S in gle S h ot M od e
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TDA5251 F1
Version 1.0
Application
2003-02-18