SC138, v1.0, Assembly Guide

Click here for a list of the parts required to build an SC138, v1.0, I2C memory card.

Experienced builders can just go ahead and populate the board. There shouldn’t be any surprises to catch you out.


This guide assumes you are familiar with assembling circuit boards, soldering, and cleaning. If not, it is recommended you read some of the guides on the internet before continuing.

First check you have all the required components, as listed in the parts list.

Before assembling it is worth visually inspecting the circuit board for anything that looks out of place, such as mechanical damage or apparent manufacturing defects.

If you have a multimeter that measures resistance or has a continuity test function, check there is not a short on the power supply tracks. Connect the probes to each terminal of capacitor C1. This should be an open circuit, not a short.

The picture below shows what a completed SC138, I2C memory card should look like.


Fit and solder the 6-pin angled female header P1.

Integrated Circuit 24LC256

Fit and solder the integrated circuit (24LC256) U1.

Be sure to fit the IC with the notch matching the legend on the circuit board.

Capacitor 100 nF (0.1 µF)

Fit and solder 100nF capacitor C1.

This capacitor can be fitted either way around, as it is not polarity dependent.

The exact value of this component is not critical. The use of very cheap capacitors within the range of about 30 to 200 nF is acceptable.


Remove any solder ‘splats’ with a brush, such as an old toothbrush.

Visually inspect the soldering for dry joints and shorts.

Clean the flux off with suitable cleaning materials.

Visually inspect again.

More information

The SC138 User Guide can be found here.

Other information about SC138 can be found here.

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