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App Note [1] Biasing

is also recommended to use active biasing to keep the currents constant as the RF power and temperature vary; this gives the most

reproducible results. Depending on the supply voltage available and the power dissipation constraints, the bias circuit may be a

single transistor or a low power operational amplifier, with a low value resistor in series with the drain supply used to sense the

current. The gate of the pHEMT is controlled to maintain correct drain current and thus drain voltage. The typical gate voltage needed

to do this is -0.5V. Typically the gate is protected with Silicon diodes to limit the applied voltage. Also, make sure to sequence the

applied voltage to ensure negative gate bias is available before applying the positive drain supply.

App Note [2] Bias Arrangement -

For Parallel Stage Bias (Recommended for general applications) -- The same as Individual Stage Bias but all the drain or gate pad DC

bypass capacitors (~100-200 pF) can be combined. Additional DC bypass capacitance (~0.01 uF) is also recommended to all DC or

combination (if gate or drains are tied together) of DC bias pads.

For Individual Stage Bias (Recommended for Saturated Applications) -- Each DC pad (Vd1,2,3 and Vg1,2,3) needs to have DC bypass

capacitance (~100-200 pF) as close to the device as possible. Additional DC bypass capacitance (~0.01 uF) is also recommended.

MTTFTable (TBD)

Backplate

Temperature

55 deg Celsius

75 deg Celsius

95 deg Celsius

Channel

Temperature

deg Celsius

deg Celsius

deg Celsius

FITs

E+

E+

E+

MTTF Hours

E+

E+

E+

Rth

C/W

C/W

C/W

Bias Conditions: Vd1=Vd2=Vd3=5.0V, Id1=100 mA, Id2=270 mA, Id3=270 mA

These numbers were calculated based on accelerated life test information and thermal model analysis received from the fabricating foundry.

36.0-40.0 GHz GaAs MMIC

Power Amplifier

Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099

Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com

Characteristic Data and Specifications are subject to change without notice.

©2006 Mimix Broadband, Inc.

Export of this item may require appropriate export licensing from the U.S. Government. In purchasing these parts, U.S. Domestic customers accept

their obligation to be compliant with U.S. Export Laws.

May 2006 - Rev 10-May-06

P1011