ATA5811-PLQX Atmel, ATA5811-PLQX Datasheet - Page 14

• Manufacturer Part Number: ATA5811-PLQX
• Manufacturer: Atmel

Specifications of ATA5811-PLQX

• Operating Temperature (min): -40C
• Operating Temperature (max): 105C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 7mm
• Product Height (mm): 0.9mm
• Product Length (mm): 7mm
• Lead Free Status / Rohs Status: Compliant

Inband Disturbers, Data Filter,
Quasi Peak Detector, Data
Slicer
14
ATA5811/ATA5812 [Preliminary]
Table 6 shows the blocking performance measured relative to -100 dBm for some other
frequencies. Note that sometimes the blocking is measured relative to the sensitivity
level (dBS) instead of the carrier (dBC).
Table 6. Blocking 6 dB Above Sensitivity Level with BER < 10
The ATA5811/ATA5812 can also receive FSK and ASK modulated signals if they are
much higher than the I1dBCP. It can typically receive useful signals at 10 dBm. This is
often referred to as the nonlinear dynamic range which is the maximum to minimum
receiving signal which is 116 dB for 20 kBaud Manchester. This value is useful if two
transceivers have to communicate and are very close to each other.
Figure 11. Close In 6 dB Blocking Characteristic and Image Response at 433.92 MHz
This high blocking performance makes it even possible for some applications using
quarter wave whip antennas to use a simple LC band-pass filter instead of a SAW filter
in the receiver. When designing such an LC filter take into account that the 3 dB block-
ing at 433.92 MHz/2 = 216.96 MHz is 43 dBC and at 433.92 MHz/3 = 144.64 MHz is
48 dBC and at 2
56 dBC. And especially that at 3
the receiver has its second LO harmonic receiving frequency with only 12 dBC blocking.
If a disturbing signal falls into the received band or a blocker is not continuous wave the
performance of a receiver strongly depends on the circuits after the IF filter. Hence the
demodulator, data filter and data slicer are important in that case.
Frequency Offset
+0.75 MHz
-0.75 MHz
+1.5 MHz
-1.5 MHz
+10 MHz
-10 MHz
-10.0
60.0
40.0
30.0
20.0
70.0
50.0
10.0
0.0
-1.0
(433.92 MHz + 226 kHz) + -226 kHz = 868.066 MHz/868.518 MHz is
Distance of Interfering to Receiving Signal [MHz]
-0.8
-0.6
-0.4
(433.92 MHz + 226 kHz)+226 kHz = 1302.664 MHz
Blocker Level
-0.2
-45 dBm
-45 dBm
-38 dBm
-38 dBm
-30 dBm
-30 dBm
0.0
0.2
0.4
0.6
0.8
-3
55 dBC/61 dBS
55 dBC/61 dBS
62 dBC/68 dBS
62 dBC/68 dBS
70 dBC/76 dBS
70 dBC/76 dBS
1.0
Blocking
4689B–RKE–04/04