MGA-31189_15 Datasheet, PDF (10/15 Pages) AVAGO TECHNOLOGIES LIMITED – 0.25W High Gain Driver Amplifier

Application Circuit Description and Layout
RFin
L3 ^C7
11X
C9
Figure 34. Circuit diagram
Vdd
C3
C2
L1
RFout
C12
C11
C10
C3
C2
IN
CTxx
C1
OUT
C7
L1 C8
L3
C9
L2
L4
AVAGO
C4
TECHNOLOGIES
C5
C6
C8
SOT-89
REV 3.2
Jul 2009
Figure 35. Demoboard
Bill of Materials
Description
Circuit
Symbol Size
For 0.45GHz⁽¹⁾
Value
Manufacturer
C2
0402
0.1µF
Murata
C3
0603
2.2µF
Murata
C7
0402
18pF
Murata
C8
0402
82pF
Murata
C9
0402
5.6pF
Murata
L1
0402
56nH
Coilcraft
L3
0402
18nH
Coilcraft
Note: NA – not required in actual PCB design
For 0.9GHz⁽²⁾
Value
0.1µF
2.2µF
100pF
39pF
NA
39nH
NA
Manufacturer
Murata
Murata
Murata
Murata
NA
Murata
NA
For 1.5GHz⁽³⁾
Value
0.1µF
2.2µF
100pF
100pF
NA
12nH
NA
Manufacturer
Murata
Murata
Murata
Murata
NA
Murata
NA
DCin
Input Matching Circuit
11X
RFin
1. Γ_mag = 0.303, Γ_ang = -163.74°
2. Γ_mag = 0.071, Γ_ang = -113.02°
3. Γ_mag = 0.106, Γ_ang = -128.48°
Output Matching Circuit
RFout
1. Γ_mag = 0.063, Γ_ang = 96.75°
2. Γ_mag = 0.039, Γ_ang = -134.54°
3. Γ_mag = 0.062, Γ_ang = 128.17°
Figure 36. Input and output tuned Gamma location for 450MHz⁽¹⁾ , 900MHz⁽²⁾ and 1.5GHz⁽³⁾
MGA-31189 is an input and output prematched component. To bias MGA-31189, a +5V supply (Vdd) is connected to the
output pin thru a RF choke, L1 (which isolates the inband signal from the DC supply). The bypass capacitors, C3 and C2
help to eliminate out of low band frequency signals from the power supply. Blocking capacitors are required for its input
(C7) and output (C8), to isolate the supply voltage from succeeding circuits. To improve on input match at 450MHz, L3
and C9 are added. The L1, together with C8 also act as the output tuning circuitry. The recommended output tuning is
for achieving best OIP3, while meeting typical specifications for other parameters.
10