Instruction Manual

MAX1471
315MHz/434MHz Low-Power, 3V/5V
ASK/FSK Superheterodyne Receiver
_______________________________________________________________________________________ 7
INPUT IMPEDANCE vs. INDUCTIVE
DEGENERATION
MAX1471 toc17
INDUCTIVE DEGENERATION (nH)
REAL IMPEDANCE (Ω)
10
10
20
30
40
50
60
70
80
90
0
1 100
f
RF
= 315MHz
L1 = 0nH
IMAGINARY IMPEDANCE
REAL IMPEDANCE
-325
-300
-275
-250
-225
-200
-175
-150
-125
-350
IMAGINARY IMPEDANCE (Ω)
INPUT IMPEDANCE vs. INDUCTIVE
DEGENERATION
MAX1471 toc18
INDUCTIVE DEGENERATION (nH)
REAL IMPEDANCE (Ω)
10
10
20
30
40
50
60
70
80
90
0
1100
f
RF
= 434MHz
L1 = 0nH
IMAGINARY
IMPEDANCE
-325
-300
-275
-250
-225
-200
-175
-150
-125
-350
IMAGINARY IMPEDANCE (Ω)
REAL IMPEDANCE
-50
-120
100 1k 1M 10M
PHASE NOISE vs. OFFSET FREQUENCY
-110
-90
-100
-60
-70
-80
MAX1471 toc19
OFFSET FREQUENCY (Hz)
PHASE NOISE (dBc/Hz)
10k 100k
f
RF
= 315MHz
-50
-120
100 1k 1M 10M
PHASE NOISE vs. OFFSET FREQUENCY
-110
-90
-100
-60
-70
-80
MAX1471 toc20
OFFSET FREQUENCY (Hz)
PHASE NOISE (dBc/Hz)
10k 100k
f
RF
= 434MHz
Typical Operating Characteristics (continued)
(Typical Application Circuit, AV
DD
= DV
DD
= HV
IN
= +3.0V, f
RF
= 434MHz, T
A
= +25°C, unless otherwise noted.)
PIN NAME FUNCTION
1 DSA- Inverting Data Slicer Input for ASK Data
2 DSA+ Noninverting Data Slicer Input for ASK Data
3 OPA+ Noninverting Op-Amp Input for the ASK Sallen-Key Data Filter
4 DFA Data-Filter Feedback Node. Input for the feedback of the ASK Sallen-Key data filter.
5 XTAL2 2nd Crystal Input
Pin Description