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EB750SOT89AH
FPD750SOT89 3.5GHz EVALUATION BOARD
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FEATURES
22dBm P1dB
14dB Gain
0.75dB Noise Figure
40dBm OIP3 (Measured @ 11dBm per tone)
Bias VD = 5V, ID = 100mA
DESCRIPTION AND APPLICATIONS
This evaluation board is a single-ended, dual biased, power amplifier. It is reactively
matched at a frequency of 3.4-3.6GHz. The active device is a Filtronic FPD750SOT89.
A lower noise figure of 0.6dB can be achieved by biasing the device at 4V, 50mA.
Biasing can be applied at the bias pins on the bottom of the board. A negative gate
voltage is required for current limiting. Ground connection should be established prior to
the gate and drain bias connections. This board is thin and flexible, so caution should be
exercised when connecting it to coaxial cables.
SCHEMATIC
-Vg
Vd
FPD750SOT89 EVAL Board
Schematic
0.01uF
1.0uF
15pF
2.7pF
Z7
2.7pF
Z14
Z6
Z0
1
RF IN
(50 Ohm)
Z13
20 Ohm
33pF
3
Z1
Z3
1
2
Z2
3
33pF
Z9
1
2
Z5
Z4
Desc.
Z0
Z1
Z2
Z3
Z4
Z5
Z6, Z13
Z7
Z8
Z9
Z10
Z11
Z12
Z14
Z8
3
1
2
Z11
3
2
Z12
RF OUT
(50 Ohm)
Z10
Value
W1=0.068" W2=0.068" W3=0.045" Microstrip Tee
W1=0.068" W2=0.030" W3=0.045" Microstrip Tee
0.030" x 0.280" Microstrip
W1=0.030" W2=0.020" W3=0.130" Microstrip Tee
0.130" x 0.100" Microstrip
0.020" x 0.200" Microstrip
0.005" x 0.550" Microstrip
0.400" x 90° Microstrip Radial Stub
0.340" x 0.480" Microstrip
W1=0.340" W2=0.220" W3=0.180" Microstrip Tee
0.180" x 0.290" Microstrip
0.220" x 0.450" Microstrip
W1=0.220" W2=0.068" W3=0.045" Microstrip Tee
0.150" x 90° Microstrip Radial Stub
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical support,
contact RFMD at (+1) 336-678-5570 or [email protected].
EB750SOT89AH
FPD750SOT89 3.5GHz EVALUATION BOARD
CIRCUIT DETAILS
The circuit used was designed using Rogers™ RO4003 material with a core thickness of
30 mils and 0.5oz copper cladding. The dielectric constant is 3.38. The PCB is mounted
on a base plate.
Recommended bias applied to the circuit is 5V, 100mA with a negative gate voltage for
current limiting. Do not exceed the absolute maximum ratings for the device given in the
device data sheet.
Q1
C1, C2, C3, C4, and C6 are ATC series 600S chip capacitors. C5 is a ATC series X7R
chip capacitor. C7 is a Tantallum capacitor
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical support,
contact RFMD at (+1) 336-678-5570 or [email protected].
EB750SOT89AH
FPD750SOT89 3.5GHz EVALUATION BOARD
FPD750SOT89 Eval board
20
15
10
5
0
dB
-5
-10
-15
-20
DB(|S(1,1)|)
-25
-30
DB(|S(2,2)|)
-35
DB(|S(2,1)|)
-40
1.5
2
2.5
3
3.5
4
4.5
Frequency (GHz)
5
5.5
6
Measured gain and return loss
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical support,
contact RFMD at (+1) 336-678-5570 or [email protected].