ATR2406 Datasheet, PDF (12/20 Pages) ATMEL Corporation – LOW IF .4 GHZ ISM TRANSCEIVER

Control Signals
The various transceiver functions are activated by the following control signals. A timing
proposal is given in Figure 5 on page 13
Table 7. Control Signals – Functions
Signal
PU_REG
PU_TRX
RX_ON
TX_ON
nOLE
Functions
Activates AUX voltage regulator and the VCO voltage regulator
supplying the complete transceiver
Activates RX/TX blocks
Activates RX circuits: DEMOD, IF AMP, IR MIXER
Activates TX circuits: PA, RAMP GEN, Starts RAMP SIGNAL at
RAMP_OUT
Disables open loop mode of the PLL
Serial Programming Bus
The transceiver is programmed by the SPI (CLOCK, DATA and ENABLE).
After setting enable signal to low condition, on the rising edge of the clock signal, the
data is transferred bit by bit into the shift register, starting with the MSB-bit. When the
enable signal has returned to high condition, the programmed information is active.
Additional leading bits are ignored and there is no check made how many clock pulses
arrived during enable low condition.
The programming of the transceiver is done by a 16 bit or 25 bit data word (for the RX
clock recovery mode).
3-wire BUS Timing
Figure 4. 3-wire Bus Protocol Timing Diagram
DATA
CLOCK
ENABLE
TL
TPER
TC
TS
TH
TEC
TT
Table 8. 3-wire Bus Protocol Table
Description
Clock period
Set time data to clock
Hold Time data to clock
Clock pulse width
Set time enable to clock
Hold time enable to data
Time between two protocols
Symbol Minimum Value
Unit
TPER
100
ns
TS
20
ns
TH
20
ns
TC
60
ns
TL
100
ns
TEC
0
ns
TT
250
ns
12 ATR2406 [Preliminary]
4779F–ISM–09/04