Datasheet

MAX7044
300MHz to 450MHz High-Efficiency,
Crystal-Based +13dBm ASK Transmitter
_______________________________________________________________________________________ 5
20
25
30
35
40
45
50
55
60
2.1 2.4 2.7 3.0 3.3 3.6
TRANSMIT POWER EFFICIENCY
vs. SUPPLY VOLTAGE
MAX7044 toc10
SUPPLY VOLTAGE (V)
TRANSMIT POWER EFFICIENCY (%)
f
RF
= 315MHz
PA 50% DUTY CYCLE AT 10kHz
T
A
= -40°C
T
A
= +85°C
T
A
= +125°C
T
A
= +25°C
30
35
40
45
50
55
60
65
70
2.1 2.4 2.7 3.0 3.3 3.6
TRANSMIT POWER EFFICIENCY
vs. SUPPLY VOLTAGE
MAX7044 toc11
SUPPLY VOLTAGE (V)
TRANSMIT POWER EFFICIENCY (%)
f
RF
= 433MHz
PA ON
T
A
= -40°C
T
A
= +85°C
T
A
= +125°C
T
A
= +25°C
15
25
20
40
35
30
55
50
45
60
2.1 2.72.4 3.0 3.3 3.6
TRANSMIT POWER EFFICIENCY
vs. SUPPLY VOLTAGE
MAX7044 toc12
SUPPLY VOLTAGE (V)
TRANSMIT POWER EFFICIENCY (%)
f
RF
= 433MHz
PA 50% DUTY CYCLE AT 10kHz
T
A
= +25°C
T
A
= -40°C
T
A
= +85°C
T
A
= +125°C
-140
-110
-120
-130
-100
-90
-80
-70
-60
-50
-40
0.01 10.1 10 100 1 10
PHASE NOISE vs. OFFSET FREQUENCY
MAX7044 toc13
OFFSET FREQUENCY (kHz)
PHASE NOISE (dBc/Hz)
2
4
6
8
10
12
14
16
18
0 1 10 100 1000 10,000
SUPPLY CURRENT AND OUTPUT POWER
vs. EXTERNAL RESISTOR
MAX7044 toc14
EXTERNAL RESISTOR (Ω)
SUPPLY CURRENT (mA)
-16
-12
-8
-4
0
4
8
12
16
POWER
CURRENT
f
RF
= 315MHz
PA ON
OUTPUT POWER (dBm)
0
6
3
12
9
15
18
-10 -2 2-6 6 10 14
SUPPLY CURRENT vs. OUTPUT POWER
MAX7044 toc15
OUTPUT POWER (dBm)
SUPPLY CURRENT (mA)
f
RF
= 315MHz
PA ON
50% DUTY CYCLE
50kHz/
div
25μs/div
FREQUENCY SETTLING TIME
MAX7044 toc16
AM DEMODULATION OF PA OUTPUT
DATA RATE = 100kHz
MAX7044 toc17
5dB/
div
3.2μs/div
OUTPUT SPECTRUM
MAX7044 toc18
10dB/
div
0dB
100MHz/div
f
RF
= 315MHz
Typical Operating Characteristics (continued)
( Typical Application Circuit , V
DD
= +2.7V, T
A
= +25°C, unless otherwise noted.) (Note 1)