Surface Mount Hyperabrupt Varactors
• Surface Mount Packages
• High Quality Factor
• Capacitance Ratio to 9.5:1
• Tape and Reel Packaging Available
• SPC Monitored Ion Implantation for Excellent
• Singles and Common Cathode Pairs
M/A-COM’s MA4ST400 series are ion-implanted, hyperabrupt
junction, silicon tuning varactors in the SOT-23 surface mount
package. These thermal oxide passivated diodes feature high
capacitance ratio and quality factor. They are well suited for
octave bandwidth tuning in the HF to UHF frequency bands. The
standard capacitance tolerance is ± 10%, with tighter tolerances
available. Capacitance matching at one or more bias voltages is
The MA4ST400 series tuning varactors are useful for octave
bandwidth tuning applications in the HF through UHF ranges.
Applications include VCOs and voltage tuned filters in radios,
cable TV tuners and test instruments where low cost and excellent
lot-to-lot repeatability are critical. Linear tuning performance is
available from 3 to 8 volts.
The model number indicated is for a single varactor. When
ordering diodes in common cathode pairs add suffix “CK.” For
example, MA4ST401CK specifies model number MA4ST401 in
common cathode pairs. To order parts on tape and reel add suffix
“T” to the end of the part number. i.e., MA4ST401CK-T.
Absolute Maximum Rating @ 25°C
Total Power Dissipation1
Junction Operating Temp.
-55°C to +125°C
-55°C to +125°C
1. At 25°C case temperature. Derate linearly to zero at 150°C.
M/A-COM Division of AMP Incorporated 3 North America: Tel. (800) 366-2266, Fax (800) 618-8883 3 Asia/Pacific: Tel.+85 2 2111 8088, Fax +85 2 2111 8087
3 Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020
AMP and Connecting at a Higher Level are trademarks.
Specifications subject to change without notice.