maximum voltage for optocoupler

Discussion in 'General Electronics Chat' started by picstudent, Feb 4, 2009.

  1. picstudent

    Thread Starter Active Member

    Feb 3, 2009
    76
    0
    Hello

    I need to switch 60V DC with a opto-coupler.

    Actually this opto is used to switch the gate of a P channel MOSFET wired as a high side switch. The opto switches the resistor divider from 60VDC to gate.

    My problem is Can I use a 80Volts opto to switch 60vdc? I plan to use quad optocoupler package with VCE of 80Volts.

    Do we need to go for 100V or above?

    My purpose is to isolate the +5V side and devices from this 60Volts area

    thanks

    Roy
     
  2. picstudent

    Thread Starter Active Member

    Feb 3, 2009
    76
    0
    Thanks a lot for the information.
    I need some more suggestions from here.
    I am basically a MCU programmer but new to electronics design. I am learning it for this project using Proteus VSM.

    I need to measure current 0 to 500ma with .1mA resolution.
    On over current (exceeds 500mA) I need to cut off also. from MCU. The software part I believe I can manage!

    For the current sensing and amplifying I have drawn a design. But I need suggessions on the factors I over looked in this .

    I have attached VSM print with full current and minimum current levels . Please advice weather it will work as I planned .I have written details in schematics also

    Please

    Roy
     
    Last edited: Feb 4, 2009
  3. picstudent

    Thread Starter Active Member

    Feb 3, 2009
    76
    0
    Thanks, Will Do it.Hope it wont create any effect on current or impedance.
    But my setup has this sort of arrangement for 12 channels. So MCU Sourcing this much current for 12 opto LEDS seems not ok for me. What you say?
    frankly ,that gave me lot of confidence.

    Thanks lot
     
  4. picstudent

    Thread Starter Active Member

    Feb 3, 2009
    76
    0
    After the opamp stages I plan to use a low pass filter. 2 ploe sallen key using the same opamp. What should be the cut off frequency? What will be a good choice or my design?

    Also can i use this filter after the multiplexer? Or else just after the opmap stages? In that case i have to construct 12 filters?
    thanks

    Roy Thomas
     
Loading...