How to create a constant current sink at M2 in my MOSfet?

[lcs81]

about MOSfet

I have ciruit in "current.jpg". Can any one tell me how to create a constant current sink at M2? Note the M3 is to turn on so that the current will sink. Initially M3 is of and current is charge up the capacitor and the capaitor voltage will increase and trigger the inverter. Some machnism will then turn on M3..


Thanks

 

[Davood Amerion]

about MOSfet

one solution:
Put one NMOS name M4 such this:
M4 source to M2 source
M4 gate to M2 gate and to M4 drain
and add one resistor or some network to prduce constant curent to M4 eg.
one resistor between VDD and Q4 drain

 

[sabu]

about MOSfet

sorry iam not getting u.actually what u r looking to do?

 

[eda_freak]

Re: about MOSfet

Post/attach a PDF of your circuit and explain clearly what is your intent here...Jpg is not viewable...Request for all the ppl.. pls post PDF of ckt.. rather than jpg image..

 

[EDA_hg81]

Thermal Design and Heat Sink Manufacturing & Testing