
Low-Cost, 308MHz, 315MHz, and 433.92MHz
FSK Transceiver with Fractional-N PLL
Typical Operating Characteristics (continued)
(Typical Operating Circuit, V PAVDD = V AVDD = V DVDD = V HVIN = +3.0V, f RF = 433.92MHz, IF BW = 280kHz. 4kbps Manchester
encoded, 0.2% BER deviation = ±50kHz, T A = +25°C, unless otherwise noted.)
BIT-ERROR RATE
RECEIVER
100
vs. AVERAGE INPUT POWER
280kHz IF BW
-100
SENSITIVITY vs. TEMPERATURE
280kHz IF BW
-94
SENSITIVITY vs. FREQUENCY DEVIATION
280kHz IF BW
10
-102
0.2% BER
f RF = 434MHz
-96
-98
0.2% BER
-104
1
f RF = 434MHz
-106
-100
-102
0.1
0.2% BER
-108
-104
0.01
f RF = 315MHz
-110
-112
f RF = 315MHz
-106
-108
-116
-114
-112
-110
-108
-106
-104
-40
-15
10
35
60
85
110
1
10
100
AVERAGE INPUT POWER (dBm)
RSSI vs. RF INPUT POWER
TEMPERATURE ( ° C)
RSSI AND DELTA vs. IF INPUT POWER
FREQUENCY DEVIATION (kHz)
FSK DEMODULATOR OUTPUT
vs. IF FREQUENCY
1.8
1.6
2.1
1.8
MAX7031 toc08
3.5
2.5
1.6
1.4
1.2
HIGH-GAIN MODE
1.5
RSSI
1.5
1.2
1.0
0.8
1.2
0.9
0.5
-0.5
0.8
0.6
0.4
0.2
0
AGC SWITCH
POINT
LOW-GAIN MODE
AGC HYSTERESIS: 3dB
0.6
0.3
0
DELTA
-1.5
-2.5
-3.5
0.4
0
-130 -110
-90
-70
-50
-30
-10
10
-90
-70
-50
-30
-10
10
10.4
10.5
10.6
10.7
10.8
10.9
11.0
50
RF INPUT POWER (dBm)
SYSTEM GAIN vs. IF FREQUENCY
48
IF INPUT POWER (dBm)
IMAGE REJECTION vs. TEMPERATURE
0
IF FREQUENCY (MHz)
NORMALIZED IF GAIN vs. IF FREQUENCY
40
UPPER SIDEBAND
f RF = 434MHz
-4
30
20
10
45dB IMAGE
REJECTION
FROM RFIN
TO MIXOUT
f RF = 434MHz
46
f RF = 315MHz
-8
-12
0
44
-10
-20
LOWER SIDEBAND
42
-16
-20
0
5
10
15
20
25
30
-40
-15
10
35
60
85
110
1
10
100
IF FREQUENCY (MHz)
TEMPERATURE ( ° C)
IF FREQUENCY (MHz)
6
_______________________________________________________________________________________