replacement for Varactor diode

[Najfi]

I'm looking for replacement of Hyperabrupt varactor diode MV1404 and MV1401 speitally some thing cheeper I need some thing with Capacitance ratio of 10+

 

[dandan]

you can consider step recovery diode which has very similar characteristic. if you need cheap cost product, the capacitance will be high, normally

 

[Najfi]

Do you have a number in your mind?. because change ratio is the main issue I need 70 pf at 1v and only 7 pf at 10-12 volt

 

[IICCEE]

you can refer the product from Macom,the GaAs diode has high Q.
The other from TOKO,philiph,toshiba...

 

[Najfi]

I need some thing cheaper. what about step recovery diode how much change rate will be availble?

 

[activewei]

Najf: check out
http://www.metelics.com/spiceStepRecovery.htm

the diode has very low capacitance. (but it is in die form)


for lower cost SRD, check out
http://www.chipdocs.com/pndecoder/datasheets/MACOM/MA44769.html

 

[zampanampa]

What is a step recovery diode?

 

[flatulent]

What is a step recovery diode?

The doping profile in this diode is optimized for the removal of the stored charge to end in a rapid dq/dt. Stored charge is generated in forward bias and removed in reverse bias. This sudden stopping of the reverse current causes a current waveform with large amplitude levels of the higher harmonics. This diode is used in frequency multipliers commonly called comb generators from the graphical shape of the graph of the frequency spectrum.