Amiga4k wrote:
Zac67,
If you do some research:
(1) 2.5" drives are 5 volt, and power is supplied thru the ribbon cable. Both + and -.
(2) you'll find that the commercial adapter for 2.5" to 3.5" consist of either an adapter module, or a modified flat cable. All have in common a 2 lead power plug. (No ground).
2.5" drives are powered through four extra wires in the ribbon cable: two +5V and two ground. Two wires are used for each supply line to allow sufficient current to flow.
Every 2.5" to 3.5" adapter I have seen include a two lead power connector, with one wire for +5 V and one wire for ground. This connector is used to power a 2.5" drive, there is not enough power available at a 2.5" drive connector to power a 3.5" drive.
Good practice is to include one ground wire for each power wire, with both wires being the same gauge. This allows all current flowing in through the positive lead to be returned to the power supply (thus following Kirchhoff's current law).
