MRF136 Datasheet, PDF (7/11 Pages) Motorola, Inc – N-CHANNEL MOS BROADBAND RF POWER FETs

400
200
Zin{ 150
f = 100 MHz
VDD = 28 V, IDQ = 25 mA,
Pout = 15 W
f
Zin{
MHz
OHMS
100 7.5 – j9.73
150 4.11 – j7.56
200 2.66 – j6.39
400 2.39 – j2.18
{27 Ω Shunt Resistor Gate–to–Ground
400
200
ZOL*
150
f = 100 MHz
VDD = 28 V, IDQ = 25 mA,
Pout = 15 W
f
ZOL*
MHz
OHMS
100 13.7 – j16.8
150 9.08 – j15.38
200 4.74 – j8.92
400 4.28 – j4.17
ZOL* = Conjugate of the
optimum load impedance into
which the device operates at
a given output power, voltage
and frequency.
Figure 16. Large–Signal Series Equivalent
Input Impedance, Zin†
Figure 17. Large–Signal Series Equivalent
Output Impedance, ZOL*
400
225
Zin & ZOL* are given
from drain–to–drain and
gate–to–gate respectively.
400
Zin
150
225
ZOL*
150
100
100
50
f = 30 MHz
50
f = 30 MHz
VDD = 28 V, IDQ = 100 mA,
Pout = 30 W
f
Zin{
MHz
Ohms
ZOL*
Ohms
30
59.3 – j24
40.1 – j8.52
50
48 – j33.5 37 – j11.9
100
20.5 – j34.2 29 – j16.5
150
4.77 – j25.4 20.6 – j19
225
3 – j9.5
13 – j16.7
400
2.34 – j3.31 10.2 – j14.3
Feedback loops: 560 ohms in series with 0.1 µF
Drain to gate, each side of push–pull FET
ZOL* = Conjugate of the optimum load imped-
ance into which the device operates at a given
output power, voltage and frequency.
REV 7
7
Figure 18. Input and Outut Impedance