mrf1535t1 Freescale Semiconductor, Inc, mrf1535t1 Datasheet - Page 10

• Manufacturer Part Number: mrf1535t1
• Description: Rf Power Field Effect Transistors
• Manufacturer: Freescale Semiconductor, Inc

MOUNTING
sumes a majority of the 0.170″ x 0.608″ source contact on
the back side of the package is in good contact with an ap-
propriate heat sink. As with all RF power devices, the goal of
the thermal design should be to minimize the temperature at
the back side of the package.
AMPLIFIER DESIGN
bipolar transistors are suitable for this device. For examples
see Freescale Application Note AN721, “Impedance
Matching Networks Applied to RF Power Transistors.”
Large - signal impedances are provided, and will yield a good
first pass approximation.
MRF1535T1 MRF1535FT1
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The specified maximum thermal resistance of 0.9°C/W as-
Impedance matching networks similar to those used with
unilateral. This coupled with the very high gain of this device
yields a device capable of self oscillation. Stability may be
achieved by techniques such as drain loading, input shunt
resistive loading, or output to input feedback. The RF test fix-
ture implements a parallel resistor and capacitor in series
with the gate, and has a load line selected for a higher effi-
ciency, lower gain, and more stable operating region.
S - parameters provides a useful tool for selection of loading
or feedback circuitry to assure stable operation. See Free-
scale Application Note AN215A, “RF Small - Signal Design
Using Two - Port Parameters” for a discussion of two port
network theory and stability.
Since RF power MOSFETs are triode devices, they are not
Two - port stability analysis with this device’s
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RF Device Data