5
5 - 174
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20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373
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Pin Descriptions
Pin Number
Function
Description
Interface Schematic
1
Vdd
Supply Voltage.
2, 11
RF1, RF2
This pin is DC coupled and matched to 50 Ohm.
Blocking capacitors are required.
Select value based on lowest frequency of operation.
3, 7, 9, 10, 12
N/C
These pins should be connected to PCB RF ground to
maximize performance.
4 - 6, 8
ACG1 - ACG4
External capacitor to ground is required. Select value for
lowest frequency of operation. Place capacitor as close
to pins as possible.
13 - 16
V1 - V4
See truth table and control voltage table.
GND
Package bottom has an exposed metal paddle that must be
connected to RF/DC Ground.
Application Circuit
HMC540LP3 / 540LP3E
1 dB LSB GaAs MMIC 4-BIT DIGITAL
POSITIVE CONTROL ATTENUATOR, DC - 5.5 GHz
v00.0605
Recommended Component Values
C1 - C3
1,000 pF ?10%
C4, C5
330 pF ?10%