Thyristor SCR anode-cathode resistance (off state)

Thread Starter

Teris

Joined Nov 4, 2017
20
Hello, I have on my hand one thyristor WESTCODE N105PH12, exactly as this one https://www.galco.com/buy/Westcode-Semiconductors/N105PH12
All the operations seems right (triggering etc.), but when it is on "OFF STATE" i measure 0.16 MΩ resistance between anode-cathode in both direction. I think that this value is very low. I would like a opinion. It is normal or low?
 

ericgibbs

Joined Jan 29, 2010
8,719
hi,
I would not get concerned over 160k resistance for that type of device, especially as it works OK.

Checked the datasheet cannot find any reference for that resistance value.
E
 

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crutschow

Joined Mar 14, 2008
23,305
You are measuring the off-state leakage current.
DMM's apply a constant current to the DUT and measure the voltage to display the resistance.
Assuming you are on the 2MΩ scale with a 200mV applied voltage full-scale, the applied current from the meter is 0.1μA.
The device is rated for 20mA at its applied voltage rating (below), so the value you measure would be fine.

What does it measure on the other resistance ranges?

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Thread Starter

Teris

Joined Nov 4, 2017
20
And on the other resistance ranges of DMM, the resistance is the same. I know that between these two terminal, the resistance must tend to infinity, in the ideal approach. Other thyristor that i had measured had about 3-4 Mega Ohm.
 
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