SI4420 Datasheet, PDF (13/33 Pages) Silicon Laboratories – No alignment required in production

Si4420
2. Power Management Command
Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
1 0 0 0 0 0 1 0 er ebb et es ex eb ew dc
POR
8208h
Bit
Function of the control bit
Related blocks
er
Enables the whole receiver chain
RF front end, baseband, synthesizer, oscillator
ebb
The receiver baseband circuit can be separately switched on
Baseband
et
Switches on the PLL, the power amplifier, and starts the
transmission (If TX register is enabled)
Power amplifier, synthesizer, oscillator
es
Turns on the synthesizer
Synthesizer
ex
Turns on the crystal oscillator
Crystal oscillator
eb
Enables the low battery detector
Low battery detector
ew
Enables the wake-up timer
Wake-up timer
dc
Disables the clock output (pin 8)
Clock output buffer
The ebb, es, and ex bits are provided to optimize the TX to RX or RX to TX turnaround time.
Logic connections between power control bits:
enable
power amplifier
et
start TX
Edge
detector
clear TX latch
(If TX latch is used)
enable
es
RF synthesizer
(osc.must be on)
enable
er
RF front end
enable baseband
circuits
ebb
(synt. must be on)
enable
oscillator
ex
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