MarkU
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Read MicroSD card with USB reader while it is connected to (powered-off) microcontroller
1 votes

The root cause of the problem is that AVR, like pretty much all ICs, requires power supply bias voltage for its inputs to behave like inputs. Internally, all of the various integrated transistors are ...

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I2C seems to work but all register reads return 0s
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4 votes

The I2C waveforms on the scope shot look like valid I2C, so that rules out common errors like forgetting to include SCL/SDA pullup resistors, or having too much bus capacitance, etc. At the bit/...

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Shorted capacitor
2 votes

It's a side effect of using ideal lumped-constant models. Ideal voltage source cannot change its terminal voltage, switch SW2 has no resistance, capacitor C1 cannot instantaneously change its voltage, ...

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Boost converter IC layout fails with increased load
7 votes

Solderless breadboard just won't work for switch-mode power supplies, there is too much parasitic inductance and capacitance. This absolutely must be laid out on a PCB. Check if the manufacturer has a ...

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Why does the emf depends on the material of the electrodes? Why is the emf independent of the distance between electrodes and amount of electrolyte?
3 votes

The half-cell potential emf develops very locally, right at the surface interface between the electrode and the electrolyte. That's why the effect is independent of the mass of electrolyte or the mass ...

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Intuition for building OR gate from NAND gates
0 votes

Yes, it is all about applying DeMorgan's law. Basically you can swap OR/AND function by inverting the output and inverting all of its inputs. DeMorgan's law is about how the Boolean AND and OR ...

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Any examples of layout where analog ground and digital ground are connected together
6 votes

There is some controversy about whether AGND-DGND should be kept completely separate, and tie together at only one physical location; or whether to connect all grounds into a single unbroken ...

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ADC bit resolution (LSB) after a gain stage
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0 votes

The resolution is still 16 bits in either case, because the resolution is determined by how many bits the ADC is designed to produce; but there can be an advantage to using an appropriate gain stage. ...

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Clarification: the role of resistance in producing heat / light (e.g. incandescent lightbulb)
1 votes

No, electrons don't really accumulate the way you imagine - what's really happening is that energy is being converted into heat, which is converted into temperature rise. Energy is an abstract idea ...

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Explain how Ohm's law applies in this tiny circuit
5 votes

I think this is the underlying problem: The voltage available "after" the R and at the door of the red LED is 6.5V, since the voltage drop across R is 5.5V. How come the red LED does not ...

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Verilog for loop not iterating
0 votes

Looking at this always for loop: always@ (posedge clk) begin for (i=1; i<(2*r+3)+1; i=i+1) begin v <= v+i; end end This verilog always clause doesn't look like it can be ...

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Copper Weight/Copper Pour Usability in Thermal Management
1 votes

Generally yes, using 1oz or 2oz copper does help add thermal mass and reduces ground system sheet resistance. One thing to be aware of when using thicker copper foil is that it affects fine-pitch ...

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Quick equivalent resistance question
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1 votes

This looks like the kind of 'trick question' seen only in homework... First thing is to trace out where the voltage nodes are (i.e. nodes that all must have the same voltage, that are all like one big ...

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Where to find datasheet for male/plug HDMI connectors?
Accepted answer
1 votes

Here's how I would approach the problem of finding a PCB mountable plug, for a system like HDMI where the PCB typically has the receptacle and the cable has the plug... One connector manufacturer that ...

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Hardware switch toggles for laptop modules
2 votes

Cutting the power connection is not sufficient to prevent the peripheral device from functioning. Most such devices are constructed in a way that has diode junctions from the power supply pins to all ...

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Parts shortage, no stock, what now? (canonical reference question)
40 votes

I work at a major analog IC manufacturer since 1990, and I have seen these kind of supply shortage cycles. These cycles come and they go, like the weather. From an IC manufacturer's perspective, the ...

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USB implementation
2 votes

Conceptually the endpoints behave like FIFO (first-in, first-out) buffers, but the USB Serial Interface Engine is more complicated than a shift register. It's been that way since even USB version 1.0. ...

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Why is my Arduino's GND pin emitting power instead of grounding it?
3 votes

Driving a motor (or any other inductive load) requires a very low-impedance ground return system. Looking at the photo, those long, thin wires and that white solderless breadboard just aren't the ...

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I need to power a device that requires 12V and 0.43A, with as small of a battery as possible
6 votes

For a battery-powered device, consider both the peak drain current and the average drain current, as well as the desired run time. The peak drain current is the maximum amount of current the load ...

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Help identify ECG signal acquisition using AD2
2 votes

If your goal is to build a real ECG analog front end -- The company I work at as an applications engineer (MaximIntegrated.com) makes ECG Analog Front End chips, MAX30001/MAX30002/MAX30003/MAX30004. I ...

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Why is this meter giving different readings depending on its orientation?
4 votes

The meter needs to be calibrated to zero by rotating the spring balance adjustment (which is the thing that looks like a slotted screwdriver head at the bottom center of the meter face). It's not ...

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Setting the output voltage of MAX8792
1 votes

The internal reference is 2V, so to get output voltage of 1.8V you need to connect FB directly to the output and use either a precision external reference or a resistive divider to apply 1.8V to REFIN....

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Maximum Typical and minimum into datasheets. What is the distribution?
19 votes

Speaking as an application engineer with 20+ years at an analog semiconductor manufacturer... What is the probability of having a component with the minimum and maximum specified value into the ...

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What happens when a digital signal reaches a receiving integrated circuit?
2 votes

(TL;DR) I've read that the integrated circuit samples the signal at its clock rate, kind of like an ADC will sample an analog signal. If the signal is high enough to drive the receiving buffer into ...

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MG996R that can rotate all the way around, but behaves like a normal servo
1 votes

According to the TowerPro MG996R datasheet, this is a Continuous Rotation Servo, "MG996R Robot servo 360° Rotation". TowerPro is the manufacturer, so I consider this datasheet the ...

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What is the difference between Bare metal, RTOS and SoC?
Accepted answer
5 votes

The statement "An RTOS is code written on bare metal" is very misleading; all operating systems are written at a level that would be considered bare metal, except we only use the term bare ...

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Total voltage doesn't add up to 5V
3 votes

The missing voltage is due to the \$V_{OL}\$ or "output voltage when signaling logic low", internal to the ATmega328's GPIO output pin. When GPIO is driving a logic 0, it does not go all the ...

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ERROR:HDLCompilers:26 - expecting 'end', found 'function'
2 votes

As of "revision 3" of the question, it's still getting stuck at line 212 at the assignment for case "%". The most recent change was replacing "function MODULO" with "...

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Where are the cathode and anode of this diode?
8 votes

Strange indeed that Diodes Incorporated datasheet does not contain the words "cathode" or "anode". Conventionally the cathode(-) side of the device is marked with a bar. So in your ...

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ATmega 328p arduino bootloader factory reset cause
Accepted answer
2 votes

Both the Arduino bootloader and the user-firmware are stored in the same flash memory, inside the ATmega328. Whenever ATmega328 is powered up or reset, the bootloader runs first, and waits briefly to ...

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