sky65238 Skyworks Solutions, Inc., sky65238 Datasheet - Page 2

• Manufacturer Part Number: sky65238
• Description: Sky65238 Power Amplifier Module With Integrated Baw Filter For Wlan Applications
• Manufacturer: Skyworks Solutions, Inc.

PRELIMINARY DATA SHEET • SKY65238 WLAN PAM WITH BAW FILTER
Technical Description
The SKY65238 PAM contains all of the needed RF matching, BAW
filtering, and DC biasing circuits. The device also provides an
output power detector voltage.
The SKY65238 is a three-stage, HBT InGaP device optimized for
high linearity and power efficiency. These features make the
device suitable for WLAN applications where power amplifier
linearity and power consumption are of critical importance.
BAW Filter
The BAW filter uses very low loss electromechanical resonators to
perform highly selective RF filtering. A BAW filter is formed by
cascading both series and shunt resonators in a ladder
configuration as shown in Figure 3.
The series and shunt resonators have slightly different resonant
frequencies. Together, they form a bandpass with steep near-
band roll off. The impedance, band shape, insertion loss, and the
2
RF_IN
May 21, 2008 • Skyworks Proprietary and Confidential information • Products and Product Information are Subject to Change Without Notice • 200743D
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
Match
Input
VCC1
Stage 1
PA
BAW Filter
Inter-Stage
Match
Figure 3. Typical BAW Filter “Ladder” Network
Figure 2. SKY65238 Block Diagram
VREF1, VREF2
VREF3
VCC2
Stage 2
Series Resonators
PA
Parallel "Shunt"
Resonators
Inter-Stage
Active Bias
Match
out of band rejection of the filter are determined by optimizing the
properties of the various resonators.
Package and Handling Information
Since the device package is sensitive to moisture absorption, it is
baked and vacuum packed before shipping. Instructions on the
shipping container label regarding exposure to moisture after the
container seal is broken must be followed. Otherwise, problems
related to moisture absorption may occur when the part is
subjected to high temperature during solder assembly.
The SKY65238 is rated to Moisture Sensitivity Level 3 (MSL3) at
250 °C. It can be used for lead or lead-free soldering. For
additional information, refer to Skyworks Application Note, PCB
Design and SMT Assembly/Rework Guidelines for MCM-L
Packages, document number 101752.
VCC3
Stage 3
VC_BIAS
PA
Detector
VCC_DET
S1308
Output
Match
BAW Filter
V_DET
RF_OUT
S1307