Hi team,
When using the THS3201 in wideband, non-inverting configuration, is there any issue with using ceramic decoupling caps instead of tantalum? The example schematic in the datasheet shows tantalum caps and I want to verify that we won't run into issues if ceramic caps were used instead.
Thanks,
Fern
Hi Fern,
This should be ok. In the past Tantalum capacitors were chosen because they are cheap and they are rated for higher voltage and capacitance values. But capacitor technology has come a long way. As a general rule of thumb it's better to use ceramics vs tantalum if possible. The main reason being that ceramic capacitors typically have lower ESR.
UltraCAD wrote a good article diving into power supply decoupling and why ESR is important: http://www.ultracad.com/articles/esrbcap.pdf
Another reason is that ceramics can be soldered at higher temperature. The plastic casing of tantalums limits the max available temp and with a push towards lead free solder, this could be a concern. There are also inherent differences in the way both capacitors are constructed which favor the ceramic architechure.
There is a lot of material on the web that discusses the differences. Kemet wrote a good article (slightly skewed towards tantalum) highlighting the advantages and disadvantages: http://www.kemet.com/kemet/web/homepage/kfbk3.nsf/vaFeedbackFAQ/0F05C4C1F74A2D2485256F170052CD15/$file/2008-11%20Update%20-%20Ceramic%20versus%20Tantalum.pdf
Hope this helps!
Let us know if you have any other questions.
Regards,Luke LapointeHigh Speed Amplifiers
Thanks Luke!