I am looking for an exact replacement for 2 voltage regulators. The first one is 78M18A (Bottom Left is marked "J1), Bottom Right is marked “1A” and in a small circle (center of the regulator is “B28”
The second Voltage regulator 79M18A (Bottom Left is marked "J1), Bottom Right is marked “6B” and in a small circle (center of the regulator is “F57”. These are not thru hole regulators and are surface mount chips that go on a Logitech z-5500 audio amplifier.
Voltage Regulators.pdf (6.2 MB)
Hello,
For the 78M18A it could be part number L78M18ABDT which is obsolete.
Take a look at part number BA17818FP-E2 as a possible substitute.
I could not find anything that we carry for the 79M18A.
A 78/79 pair are designed to work together to provide +/-18VDC and usually used for analog circuits. Being 18V makes this a rare oddball variant, the more common versions are +/-5V, +/-12V and +/-15V.
You can usually substitute a 7818 for a 78M18 because the M traditionally means half amp rated and without the M they are one amp rated.
DigiKey does not seem to carry the negative version, here’s the in stock, TO252-3 package, positive versions.
I’m not finding the 7918 in a TO252-3 package at any of my usual suppliers. I’d proably try fitting a TO-220 verison in it’s place.
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Hi james.rollo1968 ,
Don’t forget about our Adapter, Breakout Boards, for when you need to adapt package types.