RFHA1003
Device Handling/Environmental Conditions
RFMD does not recommend operating this device with typical drain voltage applied and the gate pinched off in a high humidity,
high temperature environment.
GaN HEMT devices are ESD sensitive materials. Please use proper ESD precautions when handling devices or evaluation
boards.
DC Bias
The GaN HEMT device is a depletion mode high electron mobility transistor (HEMT). At zero volts VGS the drain of the device is
saturated and uncontrolled drain current will destroy the transistor. The gate voltage must be taken to a potential lower than
the source voltage to pinch off the device prior to applying the drain voltage, taking care not to exceed the gate voltage maxi-
mum limits. RFMD recommends applying VGS = -5V before applying any VDS
.
RF Power transistor performance capabilities are determined by the applied quiescent drain current. This drain current can be
adjusted to trade off power, linearity, and efficiency characteristics of the device. The recommended quiescent drain current
(IDQ) shown in the RF typical performance table is chosen to best represent the operational characteristics for this device, con-
sidering manufacturing variations and expected performance. The user may choose alternate conditions for biasing this device
based on performance tradeoffs.
Mounting and Thermal Considerations
The thermal resistance provided as RTH (junction to case) represents only the packaged device thermal characteristics. This is
measured using IR microscopy capturing the device under test temperature at the hottest spot of the die. At the same time, the
package temperature is measured using a thermocouple touching the backside of the die embedded in the device heat sink
but sized to prevent the measurement system from impacting the results. Knowing the dissipated power at the time of the
measurement, the thermal resistance is calculated.
In order to achieve the advertised MTTF, proper heat removal must be considered to maintain the junction at or below the max-
imum of 200°C. Proper thermal design includes consideration of ambient temperature and the thermal resistance from ambi-
ent to the back of the package including heat sinking systems and air flow mechanisms. Incorporating the dissipated DC
power, it is possible to calculate the junction temperature of the device
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or customerservice@rfmd.com.
DS120216
11 of 11
RFMD [ RF MICRO DEVICES ]
