Tech Details for the IsoBlock Defender Overvoltage Protector (OVP)

12 Jun 2024

A followup to an earlier Hackernoon article that described the OVP device user manual.

That article is at The IsoBlock Defender Overvoltage Protector (OVP) here on Hackernoon. This followup article presents a quick technical summary of the device design including the schematic, the circuit board layout, and some relevant component data. Enough info is presented so that the reader could duplicate the original device implementation.

The first consideration in a design might be the choice of some pertinent components. In our case the most unusual component is the controller Integrated Circuit which is referred to as a “supervisory circuit”. This first image is a page from the Motorola Master Selection Guide that features our choice of this circuit.

The selection guide is kind of like a buffet menu. Meanwhile the actual product is more fully represented by the product data sheet.

The next document in our buffet is the electronics schematic that represents the components and their electrical connections to one another.

Another consideration of our design involves some largely mechanical electronics componets. We have this data for our connectors and some fuseholder clips on the circuit board.

The remainder of the components are all in a familiar form factor. We combine all of this information, the component data, into a Parts List as shown here next.

The next and final consideration is the printed circuit board and a “chassis” or mechanical struture to house the device. This first image shows the component values annotated to the silk screen component artwork.

The circuit board is mounted on this aluminum block heatsink.

Here are the various printed circuit artwork pieces.

There are a few pages of data related to the holes in the printed circuit board.

This image of the Gerber drill tape data for the circuit board holes ihas been cropped.

So hopefully this brief look at the device design parameters is sufficient to allow a larger understanding of what the OVP is and how it works

As always Comments, Criticisms, and Suggestions are welcome. God bless all.