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LOpen logic probe detects high, low, and floating pins

Posted on Wednesday, October 3rd, 2012 in project logs by DP

LOpen is a PIC-based logic probe that fits inside a pen. It detects if a pin is at a logic ‘High’, logic “Low”, or at high impedance (floating).

This time it’s a Logic Pen controlled by a tiny 6-pin PIC10F202. The PCB is 5 cm by 5mm so it fits just fine inside a regular ballpoint pen and have 5 leds (1 power led and 4 controllable from the PIC), over voltage protection on the probe input, reverse polarity protection using a p-fet.

Via the forum.

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Recent Comments

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