1960 MHz Application Circuit
Note: Circuit tuned for Output IP3
SXT-289 1800-2500 MHz Power Amplifier
0.1 µ F
(SIZE A)
Voltage Feed Resistor Bias Circuit (for > 7V supply)
Recommended Bias Resistor Values
Vs
Supply
Voltage(Vs)
7V
8V
10V 12V
18pF
Rbias
Rbias (Ohms)
Power Rating
18
0.5W
27
1.0W
47
1.5W
62
2.0W
390 Ω
180 Ω
39pF
0.5 pF
1000pF
15 nH
15 nH
Z=50 Ω, 8.8 °
2.7 nH
39pF
SXT-289
Z=50 Ω, 19 °
1.0 pF
RFin
Rbias
390 Ohms
180 Ohms
39pF
15nH
0.5pF
0.1uF
1000pF
18pF
RFout
15nH
2.7nH
1.0pF
39pF
SXT-289
Z=50 Ω, 13.5 °
1960 MHz Schematic
STANFORD MICRODEVICES
SOT-89 Eval Board
ECB-101499 Rev A
1960 MHz Evaluation Board Layout
Active Current Feedback Bias Circuit (for 5V supply)
0.1 µ F
(SIZE A)
Vs = 5V
22 pF
220 Ω
6
1000 pF
2
(Rohm)
4
1 UMZ1N 5
1.8K Ω
3
750 Ω
4.3 Ω
15 nH
39pF
Z=50 Ω, 35.5 °
39pF
0.5 pF
SXT-289
Z=50 Ω, 13.5 °
1960 MHz Schematic
1.0 pF
Frequency
1960 MHz
Small Signal Gain (dB) 15.3
Output IP3 (dBm)
39.7*
P1dB (dBm)
23.8
*Note: IP3 performance degraded due to lower
(4.5V) device voltage.
39pF
0.1 uF
22pF
220 Ω
1000pF
UMZ1N
1
1.8K Ω
4.3 Ω
15nH
750 Ω
0.5p
1.0p
F
F
39pF
STANFORD MICRODEVICES
XAMP EVALUATION BOARD
ECB-101872 Rev A SOT-89
NOTE: Reference Application Note AN-026 for more
information on Active Current Feedback Bias Circuit.
1960 MHz Evaluation Board Layout
ALL COMPONENTS 0603 UNLESS NOTED OTHERWISE
522 Almanor Ave., Sunnyvale, CA 94085
Phone: (800) SMI-MMIC
5
http://www.stanfordmicro.com
EDS-101157 Rev D