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4 - 7

For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824

Phone: 978-250-3343

Fax: 978-250-3373

Order On-line at www.hittite.com

Application Support: Phone: 978-250-3343 or apps@hittite.com

• 1 mil diameter wire bonds are used on vgg1 and vgg2 connections to the capacitors and 27Ω resistors.

• 0.5mil x 3mil ribbon bonds are used on rF connections

• capacitors and resistors on vgg1 and vgg2 are used to filter low frequency, <800Mhz, rF pickup

• 35Ω and 50Ω resistors are fabricated on a 5mil alumina substrate and should be suitable for use as a high

frequency termination.

• For best gain flatness and group delay variation, eccosorb can be epoxied on the transmission line

covering the center 3/4 of the transmission line length. eccosorb may also be placed partially across the

res1 pad and 35Ω resistor for improved gain flatness and group delay variation.

(The insertion of the transmission line helps reduce low frequency, <10GHz, gain ripple)

• silver-filled conductive epoxy is used for die attachment

(Backside of the die should be grounded and the GND pads are connected to the backside metal through Vias)

Device Operation

Device Mounting

these devices are susceptible to damage from electrostatic discharge. proper precautions should be observed

during handling, assembly and test.

the input to this device should be ac-coupled.

Device Power Up Instructions

1. Ground the device

2. Bring vgg1 to -0.5v (no vbias current)

3. Bring vgg2 to +1.5v (no vbias current)

4. Bring vdd to +5v (150ma to 225ma drain current)

(Initially the drain current (Vbias) will rise sharply with a small Vbias voltage, but will flatten out as Vbias

approaches 5V)

• vgg1 should be varied between -1.0v and 0v to achieve 200ma current on the drain (vbias).

• vbias may be increased to +5.5v if required to achieve greater output voltage swing.

• vgg2 may be adjusted between +1.5v and +0.3v to vary the output voltage swing.

Device Power Down Instructions

1. reverse the sequence identified above in steps 1 through 4.

HMC-AUH249

v04.0909

GaAs HEMT MMIC MODULATOR

DRIVER AMPLIFIER, DC - 35 GHz