I built a circuit using the LM3914 chip in the PDIP configuration (18 pin). When I started testing I quickly found that my +5V power was being sucked down. When I checked the circuit I found that between the +5 rail and ground (return) I had only about 15 ohms and that there was only about 15 ohms between the rails depending on which way I connected the ohmeter leads. Then I found that the actual chip had the same results. At first I thought i had a bad chip,but checking more chips produced the same result. With the plus ohmeter lead on pin 3 which is + supply voltage and the negative ohmeter lead on pins 4 or 2 I had only the 15 ohms. With the leads reversed I had a high ohm reading which is what I would have expected to find in both directions. I checked the chip description and from what I can make of it I have it connected directly, but 15 ohms is way too low. This would imply that it draws about 300 ma of current when the tech sheet says it should draw 3-5 ma.
What am I doing wrong, not understanding. I attach the LM3914 data sheet in hopes that someone can help. thanks, vern
What am I doing wrong, not understanding. I attach the LM3914 data sheet in hopes that someone can help. thanks, vern
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