Tagged Questions
0
votes
1answer
39 views
Connecting separately powered devices via serial
I have a small issue connecting an FTDI USB to 5V Serial adapter to an externally powered PIC microcontroller. They are connected via serial connection. The USB connection powered the FTDI and a ...
1
vote
3answers
124 views
Convert 0 to -150V DC to 0 to 3.3V
I have a signal that gives spikes up to negative 150V. I need to be able to determine these spikes using MCU that can sens 0 to 3.3V.
How can i adjust a signal so that it doesnt fry my MCU. It should ...
3
votes
1answer
86 views
Backward measurement of AVcc against reference voltage connected to ADC input
what you think about ADC backward measuring supply voltage in microcontroller?
It looks interesting for battery-powered devices.
The idea is:
Connect constant voltage (some voltage reference IC) to ...
0
votes
1answer
78 views
MOSFET for H-bridge
I need to power a load with 1.5V or -1.5V MCU controlled. The circuit is powered with 1.5V so for getting the negative voltage I'm going to use a H-bridge.
simulate this circuit – ...
0
votes
1answer
110 views
What is each pin's output voltage of an ATmega328P?
I would like to operate an ATmega328P in 3.3V supply alongside some other 3.3V non-5V-tolerant-peripherals. I looked up in the datasheet but I couldn't find an answer as to what is the output voltage ...
2
votes
1answer
168 views
Amplifying and Reading a 0-1 V signal into Arduino
I'm trying to read the (0~1V) output of a current transformer (CT) into the 10-bit ADC input of an Arduino Nano. The CT is sensing the L wire carrying 120V at 60Hz.
...
0
votes
1answer
75 views
7V or 12V Power Supplies for Arduino
The recommended input voltage for Arduino is 7-12V. Given that both 7V and 12V power supplies (AC-to-DC converters) are available, which voltage will be more suitable/practical? Could be in terms of ...
0
votes
2answers
123 views
3.3V signals to a shift register IC with a 5V supply
I have an SN74HC595N shift register that I want to have output 5V on the Q outputs. If I power it with 5V on VCC, can I tie the SER, SRCLK, etc. pins directly to the 3.3V digital outputs on my ...
1
vote
1answer
155 views
Control of electric actuators
I'm new to this forum and I am trying to find a solution to control three small electric linear actuators I have made for my RC controlled model aircraft, they have mini 6 volt geared brushed DC ...
3
votes
3answers
236 views
Is there any disadvantage to running an op-amp off asymmetrical voltage rails?
On a PCB I'm working with, I have analog feedbacks running through op-amps into a 3.3V microcontroller. Thus, signals outside 0-3.3V are useless, and potentially dangerous to the microcontroller. The ...
1
vote
2answers
116 views
Can an LED starve an MCU of current?
I have what is probably a really stupid question, so please don't laugh at me. Say I have a circuit with a microcontroller and an LED. This circuit is powered by two AAA batteries in series for a ...
0
votes
1answer
122 views
Multiple LED over Serial communication with Arduino
Several LEDs are being driven by Arduino. The LEDs to be lit up are sent to Arduino over serial port. When Arduino receives 12H\n over serial, it will execute ...
0
votes
0answers
81 views
Help with ATSAM4S8B
Is there anyone else who is using the Atmel ATSAM4S8B microcontroller here?
I have soldered the part onto my board. When I turn on power, the output of the internal linear regulator is only 1.01V. I ...
2
votes
4answers
287 views
How can I electronically sense the state of an LED in another device with an Arduino?
I'm working on a project to integrate an off the shelf garage door monitor with an Arduino. The base station has a pair of LED's that flash in different patterns to indicate the state of the remote ...
1
vote
1answer
901 views
Amplify 0 - 3.3V DAC signal to 0 - 10V
I have a 0-3.3V output that I wish to amplify to 0-10V.
I am using an 8-bit R2R resistor ladder connected to a National Instruments USB-6501 digital I/O device.
The application is to control a ...
0
votes
2answers
317 views
How do you calculate caps for voltage regulator circuit
In a voltage regulator circuit, how do you calculate which capacitors are placed before and after the regulator?
For example, if I'm pulling 50mA from a 5VDC regulator(L78M05) with a 9V input, how do ...
4
votes
1answer
129 views
Is the logic level of a MCU the same as the operating voltage?
The Atmega328 has an operating voltage of 1.8V to 5.5V. If I was operating it at 3V (by supplying 3V to VCC) and set a pin to high, would that pin be at 3V?
4
votes
3answers
1k views
Have I fried my Arduino UNO?
So I've recently been playing with my first Arduino, until it, for some weird reason, stopped working.
What I did:
I had it attached to a breadboard. When I say attached, I mean it was supplying ...
0
votes
2answers
212 views
5v output to 3.3v?
I have a microcontroller and a Raspberry Pi, both running off of the same 5v supply, in parallel. The microcontroller has 4 5v output pins and the other is a Raspberry Pi, that can only accept inputs ...
2
votes
1answer
156 views
Digital Circuit question - sensing input across power rails using a micro
In the Circuit shown below, I am trying to achieve the following (I know my circuit is not correct, it is an attempt).
Problem: WHen INPUT_N = 0V, the input to the microcontroller does not go low.
...
1
vote
1answer
358 views
ZXCT1009 as a current monitor
I am currently using ZXCT1009 high side monitor for monitoring the current consumption on a bus line for an embedded system we are developing. I am currently using tek scope with Labview for ...
4
votes
3answers
295 views
Lowering voltage linear [duplicate]
Possible Duplicate:
How can I use a 12 V input on a digital Arduino pin?
I want to measure a car battery voltage (range is between 10-13v). But my AVR accepts analog inputs from 0-5v. How ...
1
vote
2answers
151 views
Interfacing signals between two parts at different voltage levels
I would like to connect four output pins of a certain IC to four input pins of an AVR microcontroller (Atmega328).
I'm running the IC at VCC that varies between 3.50V and 4.00V. It outputs signals ...
3
votes
1answer
329 views
How to use an audio codec as an ADC?
I would like to add ADC functionality to a TI C6748 dev board. I need 16bit precision, but relatively low sample rate(~5K).
Not finding any suitable daughter ADC card, I am considering the ...
2
votes
2answers
3k views
Driving a large 7 segment display using a micro-controller
I need to drive a large seven segment display (segment length is a about 2 inches) using a micro-controller (PIC 16F877). I've driven normal seven segments directly from PICs without issues, but I ...
5
votes
5answers
1k 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
2answers
5k views
how can i measure voltage in range -15V to 50V with ADC in microcontroller in a single circuit arrangement for scaling? [duplicate]
Possible Duplicate:
How do I measure a negative voltage with a ADC?
How do I sample a -2 V to +2 V analog signal with a PIC microcontroller?
i want to measure the negative and positive DC ...
3
votes
1answer
241 views
Arduino LilyPad Input Voltages Below the Input Voltage in Specs
The LilyPad spec page says:
Input Voltage 2.7-5.5 V
I understand that an input voltage greater than 5.5 V would damage the device, but what if it's below 2.7 ...
3
votes
2answers
2k views
3.3v to 5v Translation
I'm in a bit of a pickle here. I need to translate 3.3v to 5v ttl levels. The devices I'm driving (12 total) are not low current devices so I don't want to interface directly, even with a current ...
1
vote
2answers
251 views
Connect a microcontroller to a gadget
Although I have average programming skills, I'm not far from being an noob concerning electronics!
I therefore want to kindly ask you to help me connect my (already programmed) Arduino Uno to the ...
5
votes
3answers
790 views
Does this amplifier work with 5V?
I'm using an Arduino to read an analog signal from an electret microphone.
Here is the circuit:
But I will be powering it with 5V from the Arduino,
So would this work okay?
Thanks!
