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EB2750QFN-AB
FPM2750QFN 0.9GHz LNA EVALUATION BOARD
FEATURES
Measured @ 900MHz
• 21 dBm Output Power
• 19 dB Small Signal Gain
• 0.6 dB Noise Figure
• 31.5 dBm OIP3 measured @ Pout = 8dBm (per tone)
● Bias 3V, 50mA
DESCRIPTION AND APPLICATIONS
The data given above is based on measurements taken on the evaluation board described
in this data sheet. This evaluation board is a balanced, dual biased, low noise amplifier. It
is reactively matched at a frequency of 700 to 900 MHz. The active device is a Filtronic
FPM2750QFN; a double-heterojunction, 750 μm gate periphery PHEMT.
Biasing can be applied at the bias pins on the top and 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
FPM2750QFN EVAL Board 0.01uF
Schematic
33pF
@ 0.9GHz
-Vg
Vd
0.01uF
33pF
20 Ohm
33pF
RF IN
50 Ohm
1.0uF
100 nH
56 nH
L1
C3
C2
50 Ohm
L3
C1
33pF
33pF
C4
L2
33pF
L4
100 nH
33pF
RF OUT
56 nH
33pF
20 Ohm
0.01uF
1.0uF
0.01uF -Vg
Vd
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical support,
contact RFMD at (+1) 336-678-5570 or [email protected]
EB2750QFN-AB
FPM2750QFN 0.9GHz LNA EVALUATION BOARD
BOARD LAYOUT
1.0uF
33pF
P4
0.01uF
33pF
L1
33pF
L2
C3
33pF
C4
33pF
A2
R2
33pF
33pF
1.0uF
0.01uF
0.01uF
P5
Ld
L4
Q1
Lg
C2
f 1SF
xxxx
A1
L3
C1
Lg
0.01uF
33pF
R1
P3
Ld
P1
P6
P2
The circuit used was designed using Roger 4350 material with a core thickness of 30 mils
and 0.5oz copper cladding. The dielectric constant is 3.48 Recommended bias applied to
the circuit is 3V, 50mA with a negative gate voltage for current limiting.
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical support,
contact RFMD at (+1) 336-678-5570 or [email protected]
EB2750QFN-AB
FPM2750QFN 0.9GHz LNA EVALUATION BOARD
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]
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