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8 Bit Computer Program Counter (4 bit Counter IC) Counting When Disabled

Awhile back I built a version of Ben Eaters 8 bit computer, on my build, I changed only AND, NOT, and OR gates to all NAND. Otherwise the design was exact. I tested it before touching it and found that it does still work. I’ve made a modification to the RAM by adding an Arduino […]

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Calculating load resistor for maximum power

How would I go about solving this? I cannot even begin solving this.

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OPENOCD set return code

I have a simple script to check for checksum match on flash. I would like to differentiate between different error states. In this case, the error is that there is a mismatch. Second error is when a device not plugged in at all. Right now I only get one error code “1” in case any […]

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Building a powerbank into a record player

My “portable” record player has a 5VDC 2A input via a barrel power jack and I want to use a normal powerbank to make it truely portable. Can I just solder the 5V output of my powerbank to the 5V input of the barrel power jack via an on-off switch? The switch is so I […]

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Effective differences between MAX485EESA+T and MAX485ESA+T?

Is anyone able to explain to me the effective difference between the MAX485EESA+T and the MAX485ESA+T? The datasheet points out that is more tolerant of ESD discharge up to 15kV, nothing more. Can it be used as drop-in replacement for the standard MAX485? Can anyone explain to me the effective electrical difference that distinguishes the […]

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Protection against power lines

I was wondering if there was any protective systems in place for if a power line falls like one that would stop the electricity going to it but I can’t find any. Does anyone know if there is and what its called?

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Low ESR decoupling capacitors – how to design against ”ringing”

I would like to use solid polymer electrolytics for decoupling in my designs instead of standard electrolytics for their longer lifespan and substantially lower ESR for marginally increased cost When choosing decoupling capacitors its frequently mentioned that the lower ESR has a greater tendency to cause ringing so its advised to use medium/high ESR capacitors. […]

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Best practice for layout of balanced audio grounds

I’m designing a simple board with a differential ADC. The inputs are from TRS jacks that will (usually) carry balanced audio signals. The datasheet, and general best practice, advises keeping analog and digital grounds separate. This makes sense to keep the digital ground currents away from the analog circuitry where they would contribute to noise. […]

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Using mesh loop to find the Output voltage

Hello! I can’t seem to get the answer to this. I have not done this type of circuit before. Can you please help me?

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RN42 Bluetooth module doesn’t turn on. Any tips for troubleshooting?

I’ve made a PCB that uses a RN42 module. Here’s the datasheet and a user’s guide (albeit for an eval kit, rather than standalone module). The situation: I power up the module with 3.3 V, and the datasheet suggests that GPIO5 status pin should start toggling immediately, signaling different stages of the pairing procedure. I’m […]