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  1. #1
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    What is the application of SCR crowbar?

    ive read somewhere that an SCR crowbar is a protective circuit that protects equipment from over-voltages.

    i wanted to ask that where does this type of circuit find applications. what type of equipment have SCR crowbar protection. is this type of protection still used or is it outdated. what are the pros and cons of using SCR crowbars for over-voltage protection.

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    crowbar overvoltage protection

    SCR crowbar protection circuit is used in Laboratory bench power supply units (etc.,) providing variable (not fixed) DC output voltages. Before feeding the DC output to the user developed circuit under test, one sets the crowbar voltage varying knob to a voltage required for the operation of circuit under test. In case the DC output voltage varying knob-setting exceeds that of crowbar set voltage, the device under test will be protected from the damage by switching off the DC output.



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    scr crowbar

    These are frequently used in PSU:s for HAM radio equipment. If something goes wrong in the PSU the crowbar cuts of the supply before the radio circuits get damaged.

    Ante



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    scr application crowbar

    okay thanx

    nice to see u here ante.

    one thing more. which topology of the SCR crowbar is preffered. the one with the zener diode that sets the reference, the one with the BJT that sets the triggering level or the one with the comparator.



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    crowbar voltage

    The one with the comparator is relatively more precise....



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    scr applications crowbar

    I have thought that crowbar mode of operation for an inverter is when we short leg of it in order to make that input fuse act and protect it.



  7. #7
    justin999
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    crowbar scr

    in ic chip, because the field oxide is so thin that it can be damaged by electrostatic destroy,so we add some electrostatic protection circuit in pads. SCR is a good type electrostatic protection circuit,
    pros small area
    cons higher trigger voltage



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    scr protection

    cons higher trigger voltage
    isnt that overcomed by using an op-amp for the triggering



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    powersupply using scr schematic

    plz visit

    radio-electronics.com/info/circuits/.../scr_over_voltage_crowbar.php



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