AP602
High Dynamic Range 4W 28V HBT Amplifier
2110-2170 MHz Application Note: Changing Icq Biasing Configurations
The AP602 can be configured to operate with lower bias current by varying the bias-adjust resistor – R2. The recommended
circuit configurations shown previously in this datasheet have the device operating with a 80 mA as the quiescent current (I
CQ
).
This biasing level represents the best tradeoff in terms of linearity and efficiency. Lowering I
CQ
will improve upon the
efficiency of the device, but degraded linearity. Increasing I
CQ
has nominal improvement upon the linearity, but will degrade
the device’s efficiency. Measured data shown in the plots below represents the AP602 measured and configured for 2.14 GHz
applications. It is expected that variation of the bias current for other frequency applications will produce similar performance
results.
V
BIAS
GND
V
PD
Icq
(mA)
20
40
60
80
100
120
140
160
R2
(ohms)
6.00k
2.76k
1.80k
1.33k
1.05k
859
723
621
V
PD
(V)
5
5
5
5
5
5
5
5
PIN_V
PD
(V)
2.53
2.61
2.67
2.73
2.79
2.84
2.89
2.94
Thermal Rise vs. Output Power vs. Icq
Vcc = 28V
80
20 mA
Thermal Rise (˚C)
60
40
20
0
17
40 mA
60 mA
80 mA
100 mA
120 mA
140 mA
160 mA
See note 4
V
CC
W = .030”
L = .980”
1000 pF
C7
100pF
19
21
23
25
27
29
Output Power (dBm)
C22
0.5 pF
See note 5
See note 3
See note 6
ACLR1 vs. Output Power vs. Icq
WCDMA, Vcc = 28V, 2140 MHz, 25
˚C
Icc vs. Output Power vs. Icq
WCDMA, Vcc = 28V, 2140 MHz, 25
˚C
Efficiency vs. Output Power vs. Icq
WCDMA, Vcc = 28V, 2140 MHz, 25
˚C
Collector Efficiency (%)
-35
Collector Current (mA)
200
150
100
50
0
29
19
21
20 mA
100 mA
40 mA
120 mA
60 mA
140 mA
80 mA
160 mA
30
25
20
15
10
5
0
19
20 mA
60 mA
100 mA
140 mA
40 mA
80 mA
120 mA
160 mA
-40
ACLR1 (dBc)
-45
-50
-55
-60
-65
19
20 mA
100 mA
40 mA
120 mA
60 mA
140 mA
80 mA
160 mA
21
23
25
27
23
25
27
29
21
23
25
27
29
Average Output Power (dBm)
Gain vs. Output Power vs. Icq
CW tone, Vcc = 28V, 2140 MHz, 25
˚C
Average Output Power (dBm)
Output Power vs. Input Power vs. Icq
CW tone, Vcc = 28V, 2140 MHz, 25
˚C
Average Output Power (dBm)
Efficiency vs. Output Power vs. Icq
CW tone, Vcc = 28V, 2140 MHz, 25
˚C
Output Power (dBm)
15
Gain (dB)
20 mA
100 mA
40 mA
120 mA
60 mA
140 mA
80 mA
160 mA
20 mA
60 mA
100 mA
140 mA
40 mA
80 mA
120 mA
160 mA
Collector Efficiency (%)
16
36
32
28
24
20
50
20 mA
40 mA
80 mA
120 mA
160 mA
40
30
20
10
0
60 mA
100 mA
140 mA
14
13
12
11
20
24
28
Output Power (dBm)
OIP3 vs. Output Power vs. Icq
CW 2-tone signal, 2140 MHz,
∆f
= 1 MHz, Vcc = 28V, 25
˚C
32
36
8
12
16
Input Power (dBm)
20
24
20
24
28
Output Power (dBm)
32
36
IMD3 vs. Output Power vs. Icq
CW 2-tone signal, 2140 MHz,
∆f
= 1 MHz, Vcc = 28V, 25
˚C
IMD5 vs. Output Power vs. Icq
CW 2-tone signal, 2140 MHz,
∆f
= 1 MHz, Vcc = 28V, 25
˚C
55
50
OIP3 (dBm)
IMD3 (dBc)
-30
-40
-50
-60
-70
-80
24
26
28
30
32
34
Output Power, PEP (dBm)
20 mA
100 mA
40 mA
120 mA
60 mA
140 mA
80 mA
160 mA
-30
-40
IMD5 (dBc)
20 mA
100 mA
40 mA
120 mA
60 mA
140 mA
80 mA
160 mA
45
40
35
30
24
26
28
30
20 mA
60 mA
100 mA
140 mA
40 mA
80 mA
120 mA
160 mA
-50
-60
-70
-80
24
26
28
30
32
34
Output Power, PEP (dBm)
32
34
Output Power, PEP (dBm)
Specifications and information are subject to change without notice
WJ Communications, Inc
•
Phone 1-800-WJ1-4401
•
FAX: 408-577-6621
•
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•
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