MAX7031 Datasheet, PDF (7/19 Pages) Maxim Integrated Products – Low-Cost, 308MHz, 315MHz, and 433.92MHz FSK Transceiver with Fractional-N PLL

Low-Cost, 308MHz, 315MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
Typical Operating Characteristics (continued)
(Typical Operating Circuit, PAV_DD = AV_DD = DV_DD = HV_IN = +3.0V, f_RF = 433.92MHz, IF BW = 280kHz. 4kbps Manchester
encoded, 0.2% BER deviation = ±50kHz, T_A = +25°C, unless otherwise noted.)
RECEIVER
S11 vs. RF FREQUENCY
0
S11 SMITH PLOT OF RFIN
-6
-12
433.92MHz
-18
-24
200 250 300 350 400 450 500
RF FREQUENCY (MHz)
INPUT IMPEDANCE
vs. INDUCTIVE DEGENERATION
90
MAX7031 toc15 _-220
f_RF = 315MHz
80
-230
70
IMAGINARY
-240
IMPEDANCE
60
-250
50
-260
40
-270
30
REAL IMPEDANCE
-280
20
1
10
INDUCTIVE DEGENERATION (nH)
-290
100
PHASE NOISE vs. OFFSET FREQUENCY
-50
f_RF = 315MHz
-60
-70
-80
-90
-100
-110
-120
100
1k 10k 100k 1M 10M
OFFSET FREQUENCY (Hz)
434MHz
400MHz _500MHz
INPUT IMPEDANCE
vs. INDUCTIVE DEGENERATION
90
f_RF = 434MHz
MAX7031 toc16 _-150
80
-160
70
IMAGINARY
-170
IMPEDANCE
60
-180
50
-190
40
-200
30
REAL IMPEDANCE
-210
20
1
10
INDUCTIVE DEGENERATION (nH)
-220
100
PHASE NOISE vs. OFFSET FREQUENCY
-50
f_RF = 434MHz
-60
-70
-80
-90
-100
-110
-120
100
1k 10k 100k 1M 10M
OFFSET FREQUENCY (Hz)
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