Tips and Cautions

We have discussed many schematics and have worked with many of you to improve system performance. We've all learned a lot in these back and forth discussions via telephone and email. Here are some tips based on these experiences.

The tab may be LIVE with Vin!

Superpower SPX has an insulated power tab on the output device so you don't need to be concerned about live Vin on the power tab, and it doesn't need an insulating or mica thermal pad. HOWEVER, the power tab has a copper center that is connected to Vin. Do not force an oversized screw into the hole, as it may shear the plastic cover and short the copper to the heat sink. If necessary, use a nylon screw.

Early Superpower SPZ and SPJ have a metal mounting tab of the output transistor connected live to Vin. This is DIFFERENT from LM78xx devices, which have the power tab connected to ground. If you replace an LM78xx with SPJ or SPL, you must use an insulator to mount the output transistor to a heat sink.

Use cheap stuff first

Superpower are expensive. Yes, they are worth it but the last thing you want to do is replace one due to a careless meter probe short circuit! When you build or modify a regulator circuit for the first time, use a cheap monolithic part until everything is working as expected. If possible, tack solder a LM78xx, LM79xx or LM1117, measure the output voltage and even power up the system to be sure all is working as expected. This way, if there are any wrong connections the damage is to a low cost part not the Superpower. Then power down and solder in the Superpower.

Remove the spacer if you wish

The leads/pins/legs come with a black spacer. This is to keep the leads properly set when they are attached during manufacture. If you wish, remove it before you solder Superpower to its PCB.

Remotely mount the output transistor

Send us a schematic or a photo

If you have questions, send us a schematic or a photo. We've become good at long distance problem solving. Especially if you're replacing a LM317 or LM337, you can send a photo and we'll try to help with which resistor to remove and which one to short across.