MRF175GV [TE]
N-CHANNEL MOS BROADBAND RF POWER FETs; N沟道MOS宽带射频功率FET
| 型号： | MRF175GV |
| 厂家： | 
TE CONNECTIVITY |
| 描述： | N-CHANNEL MOS BROADBAND RF POWER FETs |
| 文件： | 总11页 (文件大小：214K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
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SEMICONDUCTOR TECHNICAL DATA
by MRF175GU/D
The RF MOSFET Line
R
F
P
o
w
e
r
M
R
F
1
7
5
G
U
F
i
e
l
d
-
E
f
f
e
c
t
T
r
a
n
s
i
s
t
o
r
s
M
R
F
1
7
5
G
V
N–Channel Enhancement–Mode
Designed for broadband commercial and military applications using push pull
circuits at frequencies to 500 MHz. The high power, high gain and broadband
performance of these devices makes possible solid state transmitters for FM
broadcast or TV channel frequency bands.
200/150 WATTS, 28 V, 500 MHz
N–CHANNEL MOS
BROADBAND
•
Guaranteed Performance
RF POWER FETs
MRF175GV @ 28 V, 225 MHz (“V” Suffix)
Output Power — 200 Watts
Power Gain — 14 dB Typ
Efficiency — 65% Typ
MRF175GU @ 28 V, 400 MHz (“U” Suffix)
Output Power — 150 Watts
Power Gain — 12 dB Typ
Efficiency — 55% Typ
D
•
•
•
100% Ruggedness Tested At Rated Output Power
Low Thermal Resistance
G
G
Low Crss — 20 pF Typ @ VDS = 28 V
S
(F LA NG E )
CASE 375–04, STYLE 2
D
MAXIMUM RATINGS
Rating
Symbol
Value
65
Unit
Drain–Source Voltage
Drain–Gate Voltage
V
DSS
Vdc
Vdc
V
DGR
65
(R = 1.0 MΩ)
GS
Gate–Source Voltage
V
±40
Vdc
Adc
GS
Drain Current — Continuous
I
26
D
Total Device Dissipation @ T = 25°C
P
D
400
Watts
C
Derate above 25°C
2.27
W/°C
Storage Temperature Range
Operating Junction Temperature
THERMAL CHARACTERISTICS
T
–65 to +150
200
°C
°C
stg
T
J
Characteristic
Thermal Resistance, Junction to Case
Symbol
Max
Unit
R
0.44
°C/W
θ
JC
ELECTRICAL CHARACTERISTICS (T = 25°C unless otherwise noted)
C
Characteristic
Symbol
Min
Typ
Max
Unit
OFF CHARACTERISTICS (1)
Drain–Source Breakdown Voltage
(V = 0, I = 50 mA)
V
65
—
—
—
—
—
—
Vdc
mAdc
(BR)DSS
GS
D
Zero Gate Voltage Drain Current
(V = 28 V, V = 0)
I
2.5
1.0
DSS
DS
GS
Gate–Source Leakage Current
(V = 20 V, V = 0)
I
µAdc
GSS
GS
DS
(continued)
Handling and Packaging — MOS devices are susceptible to damage from electrostatic charge. Reasonable precautions in handling and
packaging MOS devices should be observed.
REV 8
1
ELECTRICAL CHARACTERISTICS — continued (T = 25°C unless otherwise noted)
C
Characteristic
Symbol
Min
Typ
Max
Unit
ON CHARACTERISTICS (1)
Gate Threshold Voltage (V = 10 V, I = 100 mA)
V
1.0
0.1
2.0
3.0
0.9
3.0
6.0
1.5
—
Vdc
Vdc
DS
D
GS(th)
Drain–Source On–Voltage (V = 10 V, I = 5.0 A)
V
DS(on)
GS
D
Forward Transconductance (V = 10 V, I = 2.5 A)
g
fs
mhos
DS
D
DYNAMIC CHARACTERISTICS (1)
Input Capacitance (V = 28 V, V = 0, f = 1.0 MHz)
C
—
—
—
180
200
20
—
—
—
pF
pF
pF
DS
GS
iss
Output Capacitance (V = 28 V, V = 0, f = 1.0 MHz)
C
oss
DS
GS
Reverse Transfer Capacitance (V = 28 V, V = 0, f = 1.0 MHz)
C
rss
DS
GS
FUNCTIONAL CHARACTERISTICS — MRF175GV (2) (Figure 1)
Common Source Power Gain
G
12
55
14
65
—
—
dB
%
ps
(V = 28 Vdc, P = 200 W, f = 225 MHz, I = 2.0 x 100 mA)
DD
out
DQ
Drain Efficiency
η
(V = 28 Vdc, P = 200 W, f = 225 MHz, I = 2.0 x 100 mA)
DD
out
DQ
Electrical Ruggedness
(V = 28 Vdc, P = 200 W, f = 225 MHz, I = 2.0 x 100 mA,
ψ
No Degradation in Output Power
DD
out
DQ
VSWR 10:1 at all Phase Angles)
NOTES:
1. Each side of device measured separately.
2. Measured in push–pull configuration.
L
2
R
1
+
C
1
0
2
8
V
B
I
A
S
0
-
6
V
C
8
C
9
-
C
3
C
4
R
2
L
1
D
.
U
.
T
.
T
2
T
1
C
6
C
5
C
1
C
2
C
7
C1 — Arco 404, 8.0–60 pF
R1 — 100 Ohms, 1/2 W
R2 — 1.0 k Ohm, 1/2 W
T1 — 4:1 Impedance Ratio RF Transformer.
T1 — Can Be Made of 25 Ohm Semirigid Coax,
T1 — 47–52 Mils O.D.
C2, C3, C7, C8 — 1000 pF Chip
C4, C9 — 0.1 µF Chip
C5 — 180 pF Chip
C6 — 100 pF and 130 pF Chips in Parallel
C10 — 0.47 µF Chip, Kemet 1215 or Equivalent
L1 — 10 Turns AWG #16 Enamel Wire, Close
L1 — Wound, 1/4″ I.D.
T2 — 1:9 Impedance Ratio RF Transformer.
T2 — Can Be Made of 15–18 Ohms Semirigid
T2 — Coax, 62–90 Mils O.D.
L2 — Ferrite Beads of Suitable Material for
L2 — 1.5ā –ā 2.0 µH Total Inductance
NOTE: For stability, the input transformer T1 should be loaded
NOTE: with ferrite toroids or beads to increase the common
NOTE: mode inductance. For operation below 100 MHz. The
NOTE: same is required for the output transformer.
Board material — .062″ fiberglass (G10),
Two sided, 1 oz. copper, ε ^ 5
r
Unless otherwise noted, all chip capacitors
are ATC Type 100 or Equivalent.
Figure 1. 225 MHz Test Circuit
REV 8
2
ELECTRICAL CHARACTERISTICS (T = 25°C unless otherwise noted)
C
Characteristic
Symbol
Min
Typ
Max
Unit
FUNCTIONAL CHARACTERISTICS — MRF175GU (1) (Figure 2)
Common Source Power Gain
G
10
50
12
55
—
—
dB
%
ps
(V = 28 Vdc, P = 150 W, f = 400 MHz, I = 2.0 x 100 mA)
DD
out
DQ
Drain Efficiency
η
(V = 28 Vdc, P = 150 W, f = 400 MHz, I = 2.0 x 100 mA)
DD
out
DQ
Electrical Ruggedness
(V = 28 Vdc, P = 150 W, f = 400 MHz, I = 2.0 x 100 mA,
ψ
No Degradation in Output Power
DD
out
DQ
VSWR 10:1 at all Phase Angles)
NOTE:
1. Measured in push–pull configuration.
B
A
L
5
L 6
C
3
1
4
C1 5
BIA S
2
8
V
C
1
8
R
1
C
1
0
C
11
C
1
2
C1 3
R
2
L
D. U. T.
C
1
C8
L
1
Z
1
Z
3
Z
5
B
1
C
3
C
4
C6
C
5
C7
B
2
Z
2
Z
4
Z
6
L
2
C
2
C
9
L
4
1
R
3
A
B
0
.
1
8
0
″
C
1
6
C
7
0
.
2
0
0
″
B1 — Balun 50 Ω Semi Rigid Coax 0.086″ O.D. 2″ Long
B2 — Balun 50 Ω Semi Rigid Coax 0.141″ O.D. 2″ Long
C1, C2, C8, C9 — 270 pF ATC Chip Cap
C3, C5, C7 — 1.0–20 pF Trimmer Cap
C4 — 15 pF ATC Chip Cap
L1, L2 — Hairpin Inductor #18 Wire
L3, L4 — 12 Turns #18 Enameled Wire 0.340″ I.D.
L5 — Ferroxcube VK200 20/4B
L6 — 3 Turns #16 Enameled Wire 0.340″ I.D.
R1 — 1.0 kΩ 1/4 W Resistor
C6 — 33 pF ATC Chip Cap
R2, R3 — 10 kΩ 1/4 W Resistor
C10, C12, C13, C16, C17 — 0.01 µF Ceramic Cap
C11 — 1.0 µF 50 V Tantalum
C14, C15 — 680 pF Feedthru Cap
Z1, Z2 — Microstrip Line 0.400″ x 0.250″
Z3, Z4 — Microstrip Line 0.870″ x 0.250″
Z5, Z6 — Microstrip Line 0.500″ x 0.250″
C18 — 20 µF 50 V Tantalum
Board material — 0.060″ Teflon–fiberglass,
ε = 2.55, copper clad both sides, 2 oz. copper.
r
Figure 2. 400 MHz Test Circuit
REV 8
3
TYPICAL CHARACTERISTICS
4
3
2
1
00 0
00 0
00 0
00 0
0
1
0
0
V
V
=
=
2
1
0
0
V
V
D
S
S
1
0
D
T
=
°
C
2
5
C
1
0
2
4
6
8
1
0
1
2
1
4
1
6
1
8
2
0
1
1
0
1 0 0
I
D
,
D
R
A
IN
C
U
R
R
E
N
T
(
AM
P
S
)
V ,
D S
D
R
AI
N
-
S
O
U
R
C
E
V
O
L
T
A
G
E
(
V
O
L
T
S
)
Figure 3. Common Source Unity Current Gain
Frequency versus Drain Current
Figure 4. DC Safe Operating Area
5
4
3
2
1
1
.
2
V
=
2
8
V
D
D
1
.
1
1
V
=
1
0
V
D
S
I
D
=
4
A
3
A
2
A
T
Y
P
I
C
A
L
D
E
V
IC
E
S
H
O
WN
G
,
V
)
=
3
V
S
(
t
h
0
0
.
9
8
1
00
mA
.
1
2
3
4
5
6
-
ā
5
0
2
5
5
0
7
5
1
0
0
1
2
5
1
5
0
1 7 5
V
G S
,
G
AT
E
-
SO
U
R
C
E
V
O
L
T
A
GE
(
V
O
LT
S
)
T ,
C
C
A
S
E
T
E
M
P
E
R
AT
U
R°
C
E
)
(
Figure 5. Drain Current versus Gate Voltage
(Transfer Characteristics)
Figure 6. Gate–Source Voltage versus
Case Temperature
1
0
0
0
0
V
f
=
0
V
z
G
S
=
1
M
H
5
0
C
os s
2
0 0
0 0
50
C
i
ss
1
C
r
s
s
2
1
0
0
0
5
1
0
1
5
2
0
2
5
V
D
,
S
D
R
A
I
N
-
S
O
U
R
C
E
V
O
L
T
A
G
E
(
V
O
L
T
S
)
Figure 7. Capacitance versus Drain–Source Voltage*
* Data shown applies to each half of MRF175GU/GV.
REV 8
4
TYPICAL CHARACTERISTICS
MRF175GV
3
2
1
00
00
00
0
3
2
2
2
2
8
4
0
0
0
0
0
I
f
=
2
5
x
1
0
0
mA
D
Q
P
=
1
2
W
i
n
=
2
2
M
H z
8
W
1
6
2
8
4
0
0
0
0
0
1
4
W
V
=
2
8
V
D
D
I
f
=
2
x
1
0
0
mA
D
Q
=
2
2
5
M
H z
0
1
2
2
4
1
2
1
4
1
6
1
8
2
0
2
2
2
4
2
6
2
8
P
i
,
n
P
OW
E
R
I
N
P
U
T
(
WAT
T
S)
V ,
D D
S
U
P
P
LY
V
O
L
T
A
G
E
(V O LTS )
Figure 8. Power Input versus Power Output
Figure 9. Output Power versus Supply Voltage
MRF175GU
2
1
0
0
0
2
1
0
0
0
8
P
i
=
1
4
W
8
n
1
1
1
1
6
0
0
0
0
0
0
0
0
0
1
1
1
1
6
0
0
0
0
0
0
0
0
0
f
=
4
00
MH z
4
2
0
8
6
4
2
4
2
0
8
6
4
2
5
0
0
MH z
1
0
W
6
W
V
=
2
8
V
D
S
I
D
=
2
x
)
1
0
0
mA
Q
f
=
4
0
0
M
H z
1
2
1
4
1
6
1
8
2
0
2
2
2
4
2
6
2
8
0
5
10
15
2
0
2
5
V
D
,
S
U
P
PLY
V
O
L
T
A
GE
(
VO
LT
S
)
P ,
i n
I
N
P
U
T
P
O
WE
R
(
W
AT
T
S
D
Figure 10. Output Power versus Supply Voltage
Figure 11. Output Power versus Input Power
MRF175GV
3
2
2
1
0
5
0
5
P
ou t
=
2
0
0
W
V
D
=
2
8
V
S
I
D
=
2
x
1
0
0
m
A
Q
1
50
W
1
0
5
5
1
0
2
0
5
0
1
00
2
0
0
5
0
0
f
,
F
R
E
Q
U
E
N
C
Y
(
M
H
z
)
Figure 12. Power Gain versus Frequency
REV 8
5
S
11
S
21
S
12
S
22
f
|S
|
φ
–174
–176
–176
–177
–178
–178
–178
–178
–179
–179
–180
–180
180
|S
|
φ
|S
|
φ
|S |
22
φ
–177
–178
–178
–178
–178
–178
–179
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–178
–179
–179
–179
–179
–179
–179
–179
–180
–180
–180
180
MHz
11
21
12
50
0.926
0.924
0.923
0.921
0.918
0.920
0.920
0.921
0.923
0.928
0.929
0.929
0.931
0.931
0.934
0.936
0.934
0.936
0.937
0.941
0.941
0.939
0.937
0.935
0.933
0.923
0.907
0.930
0.933
0.935
0.932
0.933
0.935
0.936
0.935
0.948
0.966
0.969
0.957
0.939
5.43
3.85
3.35
2.94
2.57
2.52
2.47
2.32
2.08
1.93
1.86
1.77
1.68
1.63
1.55
1.48
1.44
1.40
1.34
1.29
1.25
1.20
1.18
1.15
1.12
1.09
1.04
1.01
0.99
0.96
0.92
0.90
0.87
0.85
0.82
0.72
0.64
0.57
0.51
0.45
81
0.009
0.009
0.008
0.008
0.008
0.007
0.008
0.008
0.005
0.008
0.007
0.009
0.008
0.007
0.008
0.007
0.009
0.008
0.009
0.009
0.010
0.009
0.010
0.010
0.011
0.012
0.013
0.008
0.008
0.009
0.009
0.009
0.009
0.009
0.010
0.009
0.010
0.012
0.013
0.015
12
0.861
0.869
0.864
0.871
0.875
0.871
0.875
0.877
0.862
0.883
0.887
0.887
0.890
0.894
0.891
0.889
0.888
0.891
0.893
0.894
0.897
0.901
0.904
0.903
0.903
0.906
0.911
0.910
0.912
0.913
0.915
0.917
0.918
0.920
0.921
0.928
0.932
0.935
0.939
0.941
70
76
73
70
68
67
67
65
63
61
60
59
58
57
56
55
54
53
52
51
50
49
49
48
47
47
46
45
45
43
43
42
41
40
39
36
33
30
27
25
6
80
18
17
17
23
20
21
27
34
22
27
30
39
29
35
36
38
35
40
39
49
44
44
49
46
22
27
39
37
39
43
46
56
47
55
59
66
60
80
90
100
103
105
110
120
130
135
140
145
150
155
160
165
170
175
180
185
190
192
195
200
205
210
215
220
225
230
235
240
245
250
275
300
325
350
375
180
180
180
180
179
179
179
179
179
179
179
179
178
180
–180
180
179
179
178
178
178
178
176
180
175
179
175
178
175
178
174
177
Table 1. Common Source S–Parameters (VDS = 28 V, ID = 4.5 A) (continued)
REV 8
6
S
11
S
21
S
12
S
22
f
|S
|
φ
172
172
171
171
171
171
170
170
170
169
169
170
170
169
169
169
169
169
169
169
169
168
168
167
|S
|
φ
|S
|
φ
|S |
22
φ
176
176
176
176
176
176
176
175
175
177
177
177
177
177
177
177
177
176
176
176
176
176
176
175
MHz
11
21
12
400
405
410
415
420
425
430
435
440
445
450
455
460
465
470
475
480
485
490
495
500
505
510
515
0.943
0.945
0.948
0.956
0.963
0.966
0.968
0.970
0.971
0.978
0.978
0.977
0.978
0.977
0.973
0.973
0.970
0.964
0.960
0.957
0.957
0.951
0.948
0.943
0.41
0.40
0.40
0.39
0.38
0.37
0.37
0.36
0.36
0.32
0.31
0.31
0.31
0.30
0.29
0.29
0.28
0.28
0.28
0.27
0.27
0.26
0.26
0.25
23
0.017
0.016
0.016
0.017
0.018
0.018
0.019
0.019
0.019
0.017
0.019
0.019
0.019
0.020
0.021
0.021
0.022
0.022
0.022
0.023
0.023
0.023
0.022
0.022
75
0.946
0.946
0.944
0.949
0.946
0.947
0.948
0.949
0.952
0.965
0.964
0.965
0.967
0.963
0.966
0.967
0.967
0.963
0.965
0.963
0.963
0.966
0.965
0.966
22
22
21
21
20
20
19
19
17
17
17
16
16
15
15
15
14
14
14
13
13
13
13
71
68
74
72
70
72
75
73
71
70
73
70
73
71
72
71
74
73
71
71
70
68
72
Table 1. Common Source S–Parameters (VDS = 28 V, ID = 4.5 A) (continued)
REV 8
7
S
11
S
21
S
12
S
22
f
|S
|
φ
167
167
166
166
165
165
164
164
164
164
164
164
164
164
162
160
158
158
155
151
152
148
146
|S
|
φ
|S
|
φ
|S |
22
φ
175
175
175
174
174
174
174
174
174
174
174
174
173
172
171
170
169
168
166
164
163
161
159
MHz
11
21
12
520
525
530
535
540
545
550
555
560
565
570
575
600
625
650
675
700
750
800
850
900
950
1000
0.940
0.940
0.943
0.944
0.945
0.951
0.952
0.956
0.958
0.962
0.963
0.970
0.973
0.955
0.933
0.928
0.946
0.952
0.907
0.928
0.915
0.869
0.902
0.25
0.25
0.24
0.24
0.23
0.23
0.23
0.23
0.22
0.22
0.22
0.21
0.20
0.19
0.17
0.16
0.15
0.14
0.13
0.12
0.11
0.11
0.11
12
0.021
0.022
0.022
0.022
0.022
0.023
0.023
0.023
0.025
0.024
0.024
0.024
0.029
0.030
0.031
0.034
0.034
0.040
0.044
0.049
0.049
0.053
0.055
68
0.966
0.968
0.965
0.964
0.965
0.969
0.969
0.969
0.968
0.969
0.972
0.972
0.973
0.970
0.966
0.969
0.973
0.969
0.962
0.963
0.955
0.941
0.943
12
11
11
11
11
10
10
10
9
74
67
69
69
70
72
70
70
70
71
70
71
69
69
69
67
67
65
55
52
49
44
9
9
8
8
7
6
6
4
5
5
4
4
4
Table 1. Common Source S–Parameters (VDS = 28 V, ID = 4.5 A) (continued)
REV 8
8
INPUT AND OUTPUT IMPEDANCE
V
=
(
2
8
V
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2
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0
5
2
6
3
04
3
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Z
= Ω1 0
o
1
2
5
2
0
2
0
2
NOTE: Input and output impedance values given are measured from gate to gate and drain to drain respectively.
Figure 13. Series Equivalent Input/Output Impedance
RF POWER MOSFET CONSIDERATIONS
MOSFET CAPACITANCES
provided for general information about the device. They are
not RF design parameters and no attempt should be made to
use them as such.
The physical structure of a MOSFET results in capacitors
between the terminals. The metal oxide gate structure deter-
mines the capacitors from gate–to–drain (Cgd), and gate–to–
source (Cgs). The PN junction formed during the fabrication
of the MOSFET results in a junction capacitance from drain–
to–source (Cds).
These capacitances are characterized as input (Ciss), out-
put (Coss) and reverse transfer (Crss) capacitances on data
sheets. The relationships between the inter–terminal capaci-
tances and those given on data sheets are shown below. The
LINEARITY AND GAIN CHARACTERISTICS
In addition to the typical IMD and power gain, data pre-
sented in Figure 3 may give the designer additional informa-
tion on the capabilities of this device. The graph represents
the small signal unity current gain frequency at a given drain
current level. This is equivalent to fT for bipolar transistors.
Since this test is performed at a fast sweep speed, heating of
the device does not occur. Thus, in normal use, the higher
temperatures may degrade these characteristics to some ex-
tent.
C
iss can be specified in two ways:
1. Drain shorted to source and positive voltage at the gate.
2. Positive voltage of the drain in respect to source and zero
volts at the gate. In the latter case the numbers are lower.
However, neither method represents the actual operat-
ing conditions in RF applications.
DRAIN CHARACTERISTICS
One figure of merit for a FET is its static resistance in the
full–on condition. This on–resistance, VDS(on), occurs in the
linear region of the output characteristic and is specified un-
der specific test conditions for gate–source voltage and drain
current. For MOSFETs, VDS(on) has a positive temperature
coefficient and constitutes an important design consideration
at high temperatures, because it contributes to the power
dissipation within the device.
D
R
A
I
N
C
g d
G
A
T
E
C
C
C
=
C
+
C
gs
i
s
s
g
d
C
=
C
+
C
ds
d
s
o
s
s
g
d
= C
g d
r
s
s
C
g s
S
O
U
R
C
E
GATE CHARACTERISTICS
The gate of the MOSFET is a polysilicon material, and is
electrically isolated from the source by a layer of oxide. The
input resistance is very high — on the order of 109 ohms —
resulting in a leakage current of a few nanoamperes.
The Ciss given in the electrical characteristics table was
measured using method 2 above. It should be noted that
iss, Coss, Crss are measured at zero drain current and are
C
REV 8
9
Gate control is achieved by applying a positive voltage
slightly in excess of the gate–to–source threshold voltage,
DESIGN CONSIDERATIONS
The MRF175G is a RF power N–channel enhancement
mode field–effect transistor (FETs) designed for HF, VHF and
UHF power amplifier applications. M/A-COM RF MOSFETs
feature a vertical structure with a planar design.
M/A-COM Application Note AN211A, FETs in Theory and
Practice, is suggested reading for those not familiar with the
construction and characteristics of FETs.
The major advantages of RF power FETs include high
gain, low noise, simple bias systems, relative immunity from
thermal runaway, and the ability to withstand severely mis-
matched loads without suffering damage. Power output can
be varied over a wide range with a low power dc control sig-
nal.
VGS(th)
.
Gate Voltage Rating — Never exceed the gate voltage
rating (or any of the maximum ratings on the front page). Ex-
ceeding the rated VGS can result in permanent damage to
the oxide layer in the gate region.
Gate Termination — The gates of this device are essen-
tially capacitors. Circuits that leave the gate open–circuited
or floating should be avoided. These conditions can result in
turn–on of the devices due to voltage build–up on the input
capacitor due to leakage currents or pickup.
Gate Protection — These devices do not have an internal
monolithic zener diode from gate–to–source. If gate protec-
tion is required, an external zener diode is recommended.
Using a resistor to keep the gate–to–source impedance
low also helps damp transients and serves another important
function. Voltage transients on the drain can be coupled to
the gate through the parasitic gate–drain capacitance. If the
gate–to–source impedance and the rate of voltage change
on the drain are both high, then the signal coupled to the gate
may be large enough to exceed the gate–threshold voltage
and turn the device on.
DC BIAS
The MRF175G is an enhancement mode FET and, there-
fore, does not conduct when drain voltage is applied. Drain
current flows when a positive voltage is applied to the gate.
RF power FETs require forward bias for optimum perfor-
mance. The value of quiescent drain current (IDQ) is not criti-
cal for many applications. The MRF175G was characterized
at IDQ = 100 mA, each side, which is the suggested minimum
value of IDQ. For special applications such as linear amplifi-
cation, IDQ may have to be selected to optimize the critical
parameters.
HANDLING CONSIDERATIONS
When shipping, the devices should be transported only in
antistatic bags or conductive foam. Upon removal from the
packaging, careful handling procedures should be adhered
to. Those handling the devices should wear grounding straps
and devices not in the antistatic packaging should be kept in
metal tote bins. MOSFETs should be handled by the case
and not by the leads, and when testing the device, all leads
should make good electrical contact before voltage is ap-
plied. As a final note, when placing the FET into the system it
is designed for, soldering should be done with grounded
equipment.
The gate is a dc open circuit and draws no current. There-
fore, the gate bias circuit may be just a simple resistive divid-
er network. Some applications may require a more elaborate
bias sytem.
GAIN CONTROL
Power output of the MRF175G may be controlled from its
rated value down to zero (negative gain) by varying the dc
gate voltage. This feature facilitates the design of manual
gain control, AGC/ALC and modulation systems.
REV 8
10
PACKAGE DIMENSIONS
N O TE S :
.
U
G
1
D
I
M
.
N
E
5
T
N
M
R
S
,
O
I
O
N
I
N
G
198 2.
A
N
D
T
O
L
E
R
A
N
C
I
N
G
P
E
R
AN S I
Q RADIUS 2 PL
Y
1
4
M
M
M
B
0
.2
5
ꢀ
(
0
.
01
0
)
T
A
2
.
C
O
L
L
I
N
G
D
I
M
E
N
S
I
O
N
:
I
N
C
H
.
1
2
INCHES
MILLIMETERS
MIN MAX
DIM MIN
MAX
A
B
C
D
E
G
H
J
1
0
0
0
0
0
0
0
0
0
0
0
.
.
.
.
.
.
.
.
.
.
.
.
3
3
1
2
0
4
1
0
1
8
0
3
3
7
9
1
5
3
0
0
8
4
6
9
0
0
0
5
0
0
2
4
5
5
0
0
1
0
0
0
0
0
.
.
.
.
.
.
.
.
.
.
.
.
3
4
2
2
0
4
5
1
3
3
7
4
0
0
0
5
0
0
2
6
5
5
0
0
3
3
9
4
5
1
0
2
.
.
.
.
.
.
.
7
4
8
4
2
9
5
9
0
3
7
7
2
9
3
1
4
0
5
5
1
.
.
.
.
.
.
.
.
.
.
.
.
29
41
8 4
9 6
7 7
1 8
8 4
1 5
3 3
23
7 8
41
–B–
R
5
3
4
K
1
2
11
0
1
1
2
0
5
2
1
0
D
0
0
0
0
0
0
2
8
0
4
0
1
7
7
1
0. 11
K
N
Q
R
U
4.
1.
1.
9.
8
4
5
9
3
6
2
1
2
1
J
N
E
1
.
1
0
0
ꢀ
B
S
C
27. 94ꢀ BSC
H
S
T
Y
P
L
E
2
:
SEATING
PLANE
IN
1
.
D
D R AI
R
N
A
I
N
–T–
2
3
4
5
.
.
.
.
–A–
G
G
A
A
T
T
E
E
C
S
O
U
R
C
E
CASE 375–04
ISSUE D
Specifications subject to change without notice.
n North America: Tel. (800) 366-2266, Fax (800) 618-8883
n Asia/Pacific: Tel.+81-44-844-8296, Fax +81-44-844-8298
n Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020
Visit www.macom.com for additional data sheets and product information.
REV 8
11
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