5
20
18
16
14
12
10
Fout=26GHz
Fout=26GHz
Vd=4.5V, Vg=-1.2V
10
15
20
25
30
35
8
Vg=-1.2V, Vd=4.5V
Vg=-1.2V, Vd=5.0V
Vg=-1.4V, Vd=4.5V
Vg=-1.4V, Vd=5.0V
Vg=-1.2V, Vd=4.5V
Vg=-1.2V, Vd=5.0V
Vg=-1.4V, Vd=4.5V
Vg=-1.4V, Vd=5.0V
6
4
2
0
-11 -9
-7
-5
-3
-1
1
3
5
7
9
11
-11 -9
-7
-5
-3
-1
1
3
5
7
9
11
Input Power [1H] (dBm)
Input Power [1H] (dBm)
Figure 19 . 2H Output Power Vs Input Power @ Fout=26GHz
Figure 20 . Fundamental Supp. Vs Input Power @ Fout=26GHz
-50
-60
-70
-80
-90
Fout=15.6GHz
F1
-100
-110
-120
-130
-140
-150
-160
-170
Active
Balun
M/N
@ fo
Filter
@ 2fo
S
Amp
F2
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
Oꢀset Frequency [Hz]
Figure 21. SSB Phase Noise of frequency doubler
(Pin=+2dBm, fout=15.6GHz)
Figure 22. Top Level Schematic of Frequency doubler
Biasing and Operation
The frequency doubler MMIC consists of a balun. The The AMMP-6120 performance changes with Drain Voltage
outputs of this balun feed the gates of balanced FETs and
the drains are connected to form the single-ended output.
(Vd) and Gate bias (Vg) as shown in the previous graphs.
Improvements in output power or fundamental suppres-
This results in fundamental frequency & odd harmon- sion performance are possible by optimizing the Vg from
ics cancellation. The even harmonic drain currents are in -1.2V to -1.4V and/or Vd from 4.5 to 5.0V.
phase and thus add in phase. The input matching network
A simplified schematic of the frequency multiplier is
(M/N) is designed to provide good match at fundamental
shown in figure 22. The active balun circuit and the output
frequencies and produces high impedance mismatch to
amplifier of the circuit are self biased. The Vg negative bias
higher harmonics.
(below pinch off) is only applied to FETs ‘F1’ and ‘F2’. FETs
‘F1’ and ‘F2’ have no significant contribution to total drain
The AMMP-6120 is biased with a single positive drain
supply Vdd and a single negative gate supply using sepa- current therefore Vg cannot be used to set drain current.
rate bypass capacitors. It is normally biased with the drain
supply connected to Vd and the gate supply connected to
Vg. For most applications it is recommended to use a Vg
=-1.2V to -1.4V and Vd=4.5V to 5.0V.
It should only be used to optimize the output power
and fundamental & higher harmonics suppression of the
doubler.
Refer to the Absolute Maximum Ratings table for allowed
DC and thermal conditions.
The RF input and output ports are AC coupled thus no DC
voltage is present at either port. The ground connection is
made via the package base.”
6