BSS138 is packed in sot23, so if you want to test it, you can solder the pins (wires) as you need :), but don't forget that this is n-channel FET, you must open it with logical "0". If you are "worried" with this, find the nearest p-channel fet and use it the same way Eugene
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Re[4]: [AVR-Chat] Power reset (VCC) of some device from MICROCONTROLLER OUTPUT PIN without using relay
2010-09-03 by evgenii sorokin