SKY73025 Datasheet, PDF (6/15 Pages) Skyworks Solutions Inc. – 2300 – 2700 MHz High Gain and Linearity

PRELIMINARY DATA SHEET • SKY73025 DOWNCONVERSION MIXER
Application Circuit Design Considerations
RF Input and IF Output Matching
For best performance, RF and IF matching circuits are needed
either for a differential output application or for a single-ended
output application. A typical single-ended output application
circuit is shown in Figure 3.
The 200 Ω differential IF output impedance could be used to
connect to a differential input Surface Acoustic Wave (SAW) filter
or Variable Gain Amplifier (VGA). A 4:1 balun transformer could
also be used to match the impedance to 50 Ω for a single-ended
output application.
As noted in Figure 3, components C1, C2, L1, L2, L3, and L4 are
RF matching components; C8, C10, L9, and L10 are IF matching
components; T1 and T2 are 4:1 IF baluns.
IF Bias Resistor
Components R1 and R2 (see Figure 3) are for the IF amplifier bias
current adjustment. To operate the SKY73025 as specified in
Tables 4 and 5, these resistors are not required.
PCB Layout
The following design considerations are general in nature and
must be followed regardless of final use or configuration.
1. Paths to ground should be made as short and as low
impedance as possible.
2. The ground pad of the SKY73025 provides critical electrical
and thermal functionality. This pad is the main thermal
conduit for heat dissipation. Since the circuit board acts as the
heat sink, it must shunt as much heat as possible from the
device. Therefore, design the connection to the ground pad to
dissipate the maximum heat produced by the circuit board.
For more information on soldering the SKY73025, refer to the
Package and Handling Information section of this Data Sheet.
DC Power Supply
1. Skyworks recommends including external bypass capacitors
on the VCC voltage inputs of the device. Place the bypass
capacitors close to the VCC supply pins.
2. Components L5, L6, L7, and L8 (see Figure 3) are high-Q, low
loss inductors. These inductors must be able to pass currents
in excess of 200 mA DC.
Evaluation Board Description
The SKY73025 Evaluation Board is used to test the performance
of the SKY73025 downconversion mixer. An assembly drawing for
the Evaluation Board is shown in Figure 4 and the layer detail is
provided in Figure 5. A schematic diagram for the SKY73025
Evaluation Board is shown in Figure 6.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
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September 21, 2007 • Skyworks Proprietary and Confidential information • Products and Product Information are Subject to Change Without Notice • 200691C