Tag: LTP

Flexible CCS board prototype

I’ve been prototyping a flexible CCS PCB. The intent is to provide a cascoded FET pair with some interesting features:

  1. The lower FET can be multiple devices depending on the choice of reverse capacitance and transconductance. These include jFETs and depletion MOSFETs like the 2SK170, J310, BF862 and of course DN2540. For this purpose several pads are provided for SMD devices as well as TO-92 ones, just like the gyrator PCB. A protection Zener diode between drain and source can be soldered when using low VDSS devices.
  2. There is either a string of trimpot plus a resistor to set the CCS current manually during test given the variance in the FET parameters.  There is also an option to put a fixed resistor.
  3. There is a mu-output connection provided.

The board is very flexible and can be used for multiple purposes:

  1. shunt regulators (including VR valves)
  2. Anode load for phono preamps, drivers, LTPs, etc.
  3. LTP tail CCSs

I’ve been running some tests with excellent results.

If there is interest, I will run a batch of PCB to offer to the DIY community. 

Cheers

Ale