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Why does this device need an OR-Gate?

The device listed at the link below automatically switch the output between either a 12V (really 13.8V) power supply or a battery depending of if the power supply is on. It says it "uses two 80 ampere Schottky diodes connected as an OR-Gate to isolate the battery and power supply from each other." My question is what is the or gate used for? I understand to diodes to stop the Power supply from sucking power out of the batteries when it is off, but have on idea what advantage an or gate would give.

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Chris W
KE5GIX

"Protect your digital freedom and privacy, eliminate DRM,
learn more at http://www.defectivebydesign.org/what_is_drm"

Ham Radio Repeater Database.
http://hrrdb.com
Reply to
Chris W
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Chris W
KE5GIX

"Protect your digital freedom and privacy, eliminate DRM,
learn more at http://www.defectivebydesign.org/what_is_drm"

Ham Radio Repeater Database.
http://hrrdb.com
Reply to
Chris W

It is just two diodes in series with the two power sources, one from the battery and one from the power supply. The cathodes of the diodes are connected together forming the output. This way current flows from the source with the highest voltage. Logically that is an "or" function. It is one "or" the other. If the two sources are the same voltage, both would supply current.

Reply to
Bob Eld

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