EZLC-4421 HB Silicon Laboratories Inc, EZLC-4421 HB Datasheet - Page 15

• Manufacturer Part Number: EZLC-4421 HB
• Description: Wireless Accessories EZLink Fast Prototype Kit Hiband
• Manufacturer: Silicon Laboratories Inc

Specifications of EZLC-4421 HB

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Description of the Control Commands
1. Configuration Setting Command
2. Power Management Command
The ebb, es, and ex bits are provided to optimize the TX to RX or RX to TX turnaround time.
The RF frontend consist of the LNA (low noise amplifier) and the mixer. The synthesizer block has two main components: the VCO
and the PLL. The baseband section contains the baseband amplifier, low pass filter, limiter and the I/Q demodulator.
To decrease TX/RX turnaround time, it is possible to leave the baseband section powered on. Switching to RX mode means disabling
the PA and enabling the RF frontend. Since the baseband block is already on, the internal startup calibration will not be performed,
the turnaround time will be shorter.
The synthesizer also has an internal startup calibration procedure. If quick RX/TX switching needed it may worth to leave this block
on. Enabling the transmitter using the et bit will turn on the PA, the synthesizer is already up and running. The power amplifier almost
immediately produces TX signal at the output.
The crystal oscillator provides reference signal to the RF synthesizer, the baseband circuits and the digital signal processor part.
When the receiver or the transmitter part frequently used, it is advised to leave the oscillator running because the crystal might need
a few milliseconds to start. This time mainly depends on the crystal parameters.
It is important to note that leaving blocks unnecessary turned on can increase the current consumption thus decreasing the battery
life.
b1
Bit
0
0
1
1
Bit
ebb
Bit
ew
es
ex
eb
dc
er
et
Bit el enables the internal data register.
Bit ef enables the FIFO mode. If ef = 0 then DATA (pin 6) and DCLK (pin 7) are used for data and data clock output.
b0
0
1
0
1
15
15
1
1
Function of the control bit
Enables the whole receiver chain
The receiver baseband circuit can be separately switched on
Switches on the PLL, the power amplifier, and starts the
transmission (If TX register is enabled)
Turns on the synthesizer
Turns on the crystal oscillator
Enables the low battery detector
Enables the wake-up timer
Disables the clock output (pin 8)
14
14
0
0
Freq
Reserved
uenc
13
13
0
0
43
86
91
3
8
5
y Ba
12
12
0
0
nd
11
11
0
0
10
10
0
0
9
0
9
1
8
0
8
0
er
el
7
7
ebb
ef
6
6
x3
0
0
0
0
1
1
b1
et
5
5
x2
Related blocks
RF front end, baseband, synthesizer, crystal oscillator
Baseband
Power amplifier, synthesizer, crystal oscillator
Synthesizer
Crystal oscillator
Low battery detector
Wake-up timer
Clock output buffer
0
0
0
0
1
1
b0
es
4
4
x1
0
0
1
1
1
1
x3
ex
3
3
x0
0
1
0
1
0
1
x2
eb
2
2
Crystal Load Capacitance [pF]
…
ew
x1
1
1
x0
dc
0
0
10.0
15.5
16.0
8.5
9.0
9.5
8008h
8208h
POR
POR
Si4421
15