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4

The first regulator has an absolute max rating of 1.5 W, yet you're dissipating 4 W through it ((32-5) V times 0.15 A). In the second case it is dissipating (12-5) x 0.16 = 1.12 W, which assuming a thermal resistance of 100°C / W would give a junction temperature of 112°C + ambient temperature, very close to the maximum allowed 150°C. With such a high ...


3

It just seems to be the way it works with most AVR chips. You could make your own reference on the board if you need a fast accurate one. Or you can look to see if the 100nF cap is across AREF as noted here: https://forum.arduino.cc/t/bug-with-analogreference/22994/19 which when removed brought the ADC set to internal 1.1V ref to ready in microseconds not ...


2

Yes, the regulators are not suitable for the task you need them to perform. You are exceeding their limits. Example 1: Drop from 32V to 5V at 120mA. The regulator needs to dissipate 3.24 watts. It is rated for max 1.5W and it will overheat. Example 2: Drop from 12V to 5V at 160mA. Regulator needs to dissipate 1.12 watts. It should handle it with enough ...


2

Yes, You can keep the internal 1.1V of the Atmega 328 always on. The 1.1V bandgap-reference internal to the ATMEGA328 is also used by the brown-out detector (BOD) and the analog comparator. If either of those consumers are active the reference will remain enabled even if the ADC does not use it. For example if you enable the BOD the reference will stay on ...


2

Arduino cannot drive a relay directly, so you need a transistor driver to interface the Arduino and the relay. This is what you asked, similar to what @Momo sketched, but with TWO major changes - a Diode and an additional Resistor: simulate this circuit – Schematic created using CircuitLab A Diode reverse-biased on the coil to protect the transistor ...


1

If you're talking about the usual cheap relay modules with 8 optos that are everywhere, these already have transistors, so you don't need to add them. The arduino only drives the transistor, so its GPIOs won't be loaded. However each 5V relay uses 70mA, so that's 560mA for one 8-relay board, and 1.12A for two. If you use USB 5V port to power your arduino, ...


1

[Solved] As I added in the thread, I could solve the problem. Thanks so much for helping. Solution: In Arduino Mega the ATTiny setup uses different pins. Because intead of using: 10->reset| 11->mosi | 12->miso | 13->Sck it uses: 10->reset| 51->mosi | 50->miso | 52->Sck More info here, I highly recommend visiting this website before ...


1

You could modify this classic Forrest M Mims III design to trigger off of a PFET instead of a pushbutton switch.


1

Instead of using a FM transmitter with audio frequency input it is easier it is reasonable to do "Continuous Wave" (CW) or Pulsed Amplitude Modulation, aka Morse Code. Which will be received by radio FM receiver as clicks or beeps. Transmitter must still generate the baseband frequency for transmit, (Q2, C4, L1, ANT) but instead of modulating with ...


1

No you can't. USB isn't just an UART with different interface. UART over USB actually resembles only one of the USB device classes - CDC. There are ton's of others. Second, the USB Host and USB Device are different thing. USB to UART converter are USB Device, while the PC are USB Host. USB Printer are USB Device too. You can't connect USB Device to Device (...


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