TDA5250D2_07 Datasheet, PDF (32/94 Pages) Infineon Technologies AG – ASK/FSK 868MHz Wireless Transceiver

2.4.16 Wakeup Logic
SLAVE MODE
(default)
MODE_1 = 0
MODE_2 = 0
TDA5250 D2
Version 1.7
Functional Description
SELF POLLING
MODE
MODE_1 = 1
MODE_2 = X
Figure 2-9 Wakeup Logic States
TIMER MODE
MODE_1 = 0
MODE_2 = 1
3_modes.wmf
Table 2-31 MODE settings: CONFIG register
MODE_1
MODE_2
0
0
0
1
1
X
Mode
SLAVE MODE
TIMER MODE
SELF POLLING MODE
SLAVE MODE: The receive and transmit operation is fully controlled by an external control device
via the respective RxTx, AskFsk, PwdDD, and Data pins. The wakeup logic is inactive in this case.
After RESET or 1^st Power-up the chip is in SLAVE MODE. By setting MODE_1 and MODE_2 in the
CONFIG register the mode may be changed.
SELF POLLING MODE: The chip turns itself on periodically to receive using a built-in 32kHz RC
oscillator. The timing of this is determined by the ON_TIME and OFF_TIME registers, the duty cycle
can be set between 0 and 100% in 31.25µs increments. The data detect logic is enabled and a 15µs
LOW impulse is provided at PwdDD pin (Pin 27), if the received data is valid.
ON_TIME
OFF_TIME
ON_TIME
Action
PwdDD pin in
SELF POLLING MODE
RX ON: valid Data
min. 2.6ms _15µs
RX ON: invalid Data
t
t
Figure 2-10
timing_selfpllmode.wmf
Timing for Self Polling Mode (ADC & Data Detect in one shot mode)
Data Sheet
32
2007-02-26