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short circuit current

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leotim

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If you inverter means NOT logic gate:
When the output of an inverter is shorted (directly connected) to ground while input in logic 0 (or to VDD while input is logic 1), the output current is called "short circuit current".
 

sivakumar_tumma

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engrbabarmansoor said:
what is short circuit current in a CMOS inverter?
The pulse to the inverter is not ideal square wave . there will be some rise and fall times.

similarly there will dealy in the response of NMOS and PMOS.

Because of these, there will be chance of ,for sometime, both the NMOS and PMOS will be on, shorting the Vdd to the ground. Since the impednace is less, there will large current passing through the inverter.

This current is called shortcircuit current.
 

barmak

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short circuit currrent in any block with output usually means the maximum current that output can give for long time when output is connected to ground
 

RDRyan

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I agree with sivakumar_tumma
I think short circuit current is the current from VDD to VSS when both PMOS and NMOS are turned on.
When the input is from low to high or high to low, the input of voltage of the inverter will reach a middle voltage between VDD and VSS, and then the PMOS and NMOS of inverter both are turn on. and the static current from VDD to VSS is very large.

Ryan
 

turbina

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the value of cmos short current depends of vdd, .
at 5volts .....2-5milliamperes
at 15volts more think 10-15milliamperes
 

santhosh.mandugula

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sivakumar_tumma said:
engrbabarmansoor said:
what is short circuit current in a CMOS inverter?
The pulse to the inverter is not ideal square wave . there will be some rise and fall times.

similarly there will dealy in the response of NMOS and PMOS.

Because of these, there will be chance of ,for sometime, both the NMOS and PMOS will be on, shorting the Vdd to the ground. Since the impednace is less, there will large current passing through the inverter.

This current is called shortcircuit current.
This will happen during rising and falling edges of the input signal.
 

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