SKY12340-364LF Datasheet, PDF (7/13 Pages) Skyworks Solutions Inc. – 300 kHz - 2.0 GHz Five-Bit Digital Attenuator with Serial-to-Parallel Driver

DATA SHEET • SKY12340-364LF FIVE-BIT DIGITAL ATTENUATOR
Table 6. SKY12340-364LF Truth Table
J1 to J2
Attenuation
Reset
0.5 dB
1.0 dB
Serial Data Input
2.0 dB
4.0 dB
8.0 dB
Insertion loss
1
0
0
0
0
0
0.5 dB
1
1
0
0
0
0
1.0 dB
1
0
1
0
0
0
2.0 dB
1
0
0
1
0
0
4.0 dB
1
0
0
0
1
0
8.0 dB
1
0
0
0
0
1
15.5 dB
1
1
1
1
1
1
Insertion loss
0
X
X
X
X
X
Note: “1” = VH = +1.7 V to +5 V. “0” = VL = 0 to +0.6 V. “X” = don’t care. This Table shows the logic required for the major bits and full attenuation. Bit states need to be used in
combination to set the sum of the bits selected.
Evaluation Board Description
The SKY12340-364LF Evaluation Board is used to test the
performance of the SKY12340-364LF digital attenuator. An
assembly drawing for the Evaluation Board is shown in Figure 15
and an Evaluation Board schematic diagram is shown in
Figure 16. Table 7 provides the Evaluation Board Bill of Materials
(BOM) list.
The Evaluation Board includes the required charge pump
capacitor between pins 30 and 31. It also includes the negative
voltage holding capacitor required from pin 28 to ground.
A capacitor is added to pin 31 to ground any noise on the DC
supply line.
Package Dimensions
The PCB layout footprint for the SKY12340-364LF is shown in
Figure 17. Typical case markings are noted in Figure 18. Package
dimensions for the 32-pin QFN are shown in Figure 19, and tape
and reel dimensions are provided in Figure 20.
Package and Handling Information
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 SKY12340-364LF is rated to Moisture Sensitivity Level 1
(MSL1) at 260 C. It can be used for lead or lead-free soldering.
For additional information, refer to the Skyworks Application Note,
Solder Reflow Information, document number 200164.
Care must be taken when attaching this product, whether it is
done manually or in a production solder reflow environment.
Production quantities of this product are shipped in a standard
tape and reel format. For packaging details, refer to the Skyworks
Application Note, Discrete Devices and IC Switch/Attenuators
Tape and Reel Package Orientation, document number 200083.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
201111B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • January 5, 2010
7