ATAB5423-3-WB Atmel, ATAB5423-3-WB Datasheet - Page 17

• Manufacturer Part Number: ATAB5423-3-WB
• Description: KIT DEMO 315MHZ BLACKBIRD
• Manufacturer: Atmel
• Type: Transceiver, UHFr

Specifications of ATAB5423-3-WB

• Frequency: 315MHz
• Product: RF Modules
• For Use With/related Products: ATA5423
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ATAB-5423-3-WB

3.7
3.8
3.9
4841D–WIRE–10/07
In-band Disturbers, Data Filter, Quasi-peak Detector, Data Slicer
DEM_OUT Output
RSSI Output
If a disturbing signal falls into the received band or a blocker is not continuous wave, the perfor-
mance of a receiver strongly depends on the circuits after the IF filter. The demodulator, data
filter and data slicer are important, in that case.
The data filter of the ATA5423/ATA5425/ATA5428/ATA5429 implies a quasi-peak detector. This
results in a good suppression of the above mentioned disturbers and exhibits a good carrier to
Gaussian noise performance. The required useful signal to disturbing signal ratio to be received
with a BER of 10
BR_Range_2)/6 dB (BR_Range_3) in FSK mode. Due to the many different waveforms possible
these numbers are measured for signal as well as for disturbers with peak amplitude values.
Note that these values are worst case values and are valid for any type of modulation and mod-
ulating frequency of the disturbing signal as well as the receiving signal. For many combinations,
lower carrier to disturbing signal ratios are needed.
The internal raw output signal of the demodulator Demod_Out is available at pin DEM_OUT.
DEM_OUT is an open drain output and must be connected to a pull-up resistor if it is used (typi-
cally 100 k ) otherwise no signal is present at that pin.
The output voltage of the pin RSSI is an analog voltage, proportional to the input power level.
Using the RSSI output signal, the signal strength of different transmitters can be distinguished.
The usable dynamic range of the RSSI amplifier is 70 dB, the input power range P(RF
–115 dBm to –45 dBm and the gain is 8 mV/dB.
typical device at 433.92 MHz with VS1 = VS2 = 2.4 to 3.6 V and T
matched input according to
3.3 dB and at 868.3 MHz about 2.7 dB more signal level, at 345 MHz about 0.8 dB and at
315 MHz about 1 dB less signal level is needed for the same RSSI results.
Figure 3-6.
Typical RSSI Characteristic versus Temperature and Supply Voltage
–3
is less than 12 dB in ASK mode and less than 3 dB (BR_Range_0 to
1100
1000
ATA5423/ATA5425/ATA5428/ATA5429
900
800
700
600
500
400
-120
Table 3-2 on page 12
-110
min.
-100
-90
P
typ.
RF_IN
Figure 3-6
and
-80
(dBm)
Figure 3-1 on page
-70
max.
shows the RSSI characteristic of a
-60
amb
-50
= –40°C to +85°C with a
11. At 915 MHz about
-40
IN
) is
17