Tagged Questions

0
votes
1answer
147 views

FTDI/MCU design question to detect boot mode

MCU(ATMega 8 series) on my device has two operating modes Bootloader mode Normal operation The firmware can be upgraded through MCU USART interface. To connect to PC I want to place ...
1
vote
1answer
161 views

USB connection with overvoltage protection

I'm trying to design a circuit from scratch with a 5V supply, USB connectivity and an AVR chip, for the sake of learning more about building power supplies, and implementing over-voltage protection on ...
1
vote
2answers
347 views

Communication between two AVR microcontrollers over SPI with different power supplies

I have two ATMEGA32 microcontrollers. First one has the following power supply: 220VAC-line filter-transformer-bridge rectifier-filter-voltage regulator-5VDC. Another one is powered by USB 5VDC. So ...
5
votes
5answers
439 views

Running my atmega8 at 5.5V, risky?

I have just received my first microcontroller, an Atmega8. I will soon be making a voltage regulation circuit for it to run at 5V, but I don't have all the parts yet. Instead, I have a 5V DC 1000mA ...
1
vote
1answer
325 views

Is this switching power controller compromise wise?

TL;DR: Looking for all kinds of advice :-) Especially related to pushing "backwards" power into a MC34063 based step-up switching controller at times. I'm building a device with an AVR ...
0
votes
3answers
3k views

Building a digitally controlled bench power supply using an AVR

This article describes a rather nice solution for building a current- and voltage- controlled benchtop power supply using a DC supply in the range of 20-30 volts and some additional down-regulation ...
1
vote
1answer
387 views

building a variable bench supply using microAtx 24pin atx then using attiny44 as voltmeter

Ideally I should have a bench supply so I don't have to keep buying 9v batteries. I've taken a micro atx psu out of a pc I have. It has a 24 pin ATX connector. I'm not going to take apart the psu ...
5
votes
2answers
238 views

Would pictured circuit be good enough to power ATmega162?

I've read the datasheet and the application notes elated to AVR Hardware Design Considerations and EMI. From them and various Internet sources I came up with pictured design for power supply circuit ...
2
votes
2answers
311 views

Correct EL Driver Rating for 8 Channel Sequencer

I'm trying to use an 8 channel EL sequencer (found here) to control eight 10-foot segments of EL wire. I'm having trouble figuring out what the appropriate length rating is that I need on an ...
4
votes
4answers
1k views

Easiest and Best PoE Ethernet Chip/Micro/Design for DIY Interface with Custom Arduino Board (AVR Solution)

I am looking for a PoE Ethernet chip that I can incorporate in a design I plan on using along with some of the Arduino features. I would prefer to implement a standalone mcu for the Ethernet device ...