Questions tagged [5v]

Questions regarding 5V level signals, level-shifting, and circuits.

Filter by
Sorted by
Tagged with
0
votes
0answers
51 views

Safety when creating electronics enclosure

I'm designing an electronics enclosure to be placed in series with the power cord for a device for control purposes and would like to know safest methods to do power breakouts within the plastic box. ...
0
votes
2answers
62 views

5v to 12 Power Supply

I have really no idea about electronics. I am trying to provide IR lighting for my night camera that I use with the raspberry Pi. The Pi is powered by a 5v usb power bank. The IR requires 12v. I ...
3
votes
1answer
36 views

Automotive Sensor Output

Why does the automotive industry sticks with 5V sensor outputs instead of something like 4-20 mA? Wouldn't it be a solution less prone noise? What are the advantages in using a 5V output instead of a ...
0
votes
1answer
42 views

Automatic switching to the changed set of TTL inputs

I have 2 sets of 4 logical inputs. All inputs are active-low 5V TTL level lines with 4k7 pull-up resistors, as they may be pulled to ground by a a user pressing a switch or flipping a transistor with ...
0
votes
1answer
31 views

Power supply noise/ringing caused by Jetson Nano booting and data processing

I have a board where I use the Jetson Nano module as the CPU. During the power-on sequence and data processing the Jetson introduces about 400mv peak to peak noise/ringing on the 5V (SMPS) rail ...
0
votes
1answer
22 views

Atmega32u4 on 5V. MISO from IC on 3.3V?

I'm running an Atmega32u4 on a 5V circuit. However, I'm also using a Bluetooth IC [MDBT40] on a 3.3V circuit that I'm setting down from 5V with a linear regulator. I'm turning both SCK and MOSI to 3....
0
votes
1answer
50 views

Will my project source most of its current from the battery?

I have a video game controller project that requires a battery. This is because the console doesn't provide enough current on the 5V rail to fully power the project. The battery (and charge circuit) ...
0
votes
1answer
84 views

High speed logic level converter circuit

I have been trying to make a 3.3V circuit controlled by an Arduino (5V logic.) I have used a logic converter circuit similar to the SparkFun/Adafruit ones. My problem is that whenever i try to ...
0
votes
0answers
18 views

Can I use a smartphone with battery circuit powered 5v directly without battery?

I tried to supply power 5v to the phone's battery circuit, and I noticed there's 2 line B+ and P+ that could be supplied. and it keeps restarting if supplied 5v to B+, but P+ looks like working as ...
3
votes
2answers
91 views

VUSB / +5V selector to safely power KNX project

I'm working on a board that will include a TP-UART IC + an ATMEGA328-AU on the same device. I'm now facing the potential risk of damaging the host computer or the TP-UART IC if I'm mishandling the ...
0
votes
0answers
41 views

Calculation of the resistors values in a voltage divider

I'm working on a circuit where a 3.3v flash memory, which comunicate with SPI protocol, has to be interfaced to an 8-bit PIC microcontroller working at 5v. For the MISO signal there should not be any ...
0
votes
1answer
36 views

Fusing an In-Wall LED Application

I'm building my own PCB to power 8 in-wall LED's for a stairwell. I'd like to protect the LED's with fuses, but I'm unclear on how the voltage on fuses work. My specs are as follows: LEDs: 5V, ...
1
vote
0answers
14 views

5-V CPLD family in-circuit programmability

I have a need for a relatively small amount of 5V-logic (active at power-up) that would perfectly fit a package like that of the ATF750CL CPLD from Atmel/Microchip, the DigiKey page for these devices ...
-1
votes
2answers
85 views

How to do serial communication between 3.3V and 5V devices using THT components?

I know that there are many questions dealing with logic level conversion/shifting between 3.3V and 5V devices, but my goal is to do do this with standard breadboard parts, so either discrete parts or ...
3
votes
5answers
554 views

Obtaining 4-4.2V rail from 5V output of LM7805 voltage regulator

I'm creating a numitron clock with 4xIV-9 tubes (seven-segment filament displays) and have decided to illuminate them using shift registers controlled by an arduino. Each segment takes a voltage of 4-...
0
votes
2answers
52 views

Is it okay to connect directly power supply to usb 5v? +<->+ & - <->- to maintain power?

I am working on an extention cable for my PC usb hub. It goes about 5m using UTP 5e cable, it sometimes can read the data from usb, sometimes it can't. I figured, it is because of voltage drop. So I ...
0
votes
0answers
64 views

Home project about detecting harmful gases

I am designing a PCB for detecting harmful gases (below is the schematic in Eagle). I have used MQ7 and MQ135 sensors, and the ESP32 WROOM32D MCU. For the power supply, I have used HLK-PM03 since I'...
0
votes
1answer
56 views

Can you power a 3.3 led with an arduino 5v output?

I have a led that can handle 10 milliamps at 3.3v. Can I use a voltage divider and a plus resistor to power it from an arduino nano 5v digital pin? Maybe something like this. simulate this circuit &...
0
votes
1answer
51 views

Bidirectional 5V-3.3V level shifter and ADS1115 resistor implementation reduction

I’m using the ADS1115 with 5V because my measuring device provides 0 to 5V measurements but since the microcontroller is not tolerant to 5V, I need to shift it down to 3.3V. I plan to use the BSS138 ...
0
votes
2answers
60 views

Digital 5V signal through a long copper cable with EMI noise

I'm designing a zigbee switch with additional capabilities in order to give it some flexibility. The main idea is to put this design in the interconection boxes that are in my walls. So, this PCB ...
-1
votes
1answer
46 views

Reversing the input of a transistor

I want to detect if a 12V DC line has power or not. I want the transistor to work like this: If pin 2 has 5-12V, pin 1 and 3 should be disconnected and should stop the flow of 5V 2A across pin 1 and 3....
0
votes
2answers
92 views

Can 12V relay be used instead of 5V relays?

I have the project of making a touch switch using the IRFZ44N MOSFET for making a small led glow and stop glowing when I touch the probes. I thought of using a relay if I have to make a bulb glow, by ...
1
vote
2answers
404 views

Best MOSFET to control small 12v load with NodeMCU? [closed]

I am pretty familiar with Arduino, and I will be using a NodeMCU for an upcoming project I'm doing. I have never used a NodeMCU before. I am using it along with a few sensors to turn on and off some ...
3
votes
2answers
83 views

Charging an 8 V, 100 mA device via USB (5 V, 500 mA)

I have a shaver (Philips QP2530) which I would like to be able to charge via a USB outlet (in order to allow me to use it on a motorcycle ride from London to Tokyo, but that's another story!) The ...
1
vote
2answers
74 views

how to choose level shifters for serial / UART

I have so far been using some MAX3323EEPE chips for shifting between 3.3V and 5V logics on serial / UART communications. This is quite some stuff to solder on a PCB, and the chip is a bit expansive. I ...
0
votes
1answer
47 views

teensy 3.5 interfacing with RockBlock 9603

I want to interface a Teensy 3.5: https://www.pjrc.com/store/teensy35.html With a RockBlock 9603: https://www.rock7.com/products-rockblock-9603 I will give 3.3V input to the Teensy, and 5V input ...
0
votes
0answers
44 views

Which relay would be better to use in IoT switch for industrial and home purpose, 5V or 12v?

We are designing a IoT switch for controlling industrial and home switches and we are not sure what relay should we be using, 5V or 12V. Please let me know which one would be the best to use.
1
vote
1answer
42 views

How to keep a stable output voltage from changing input voltage

I'm learning about solar panels and bought a 6V panel and a 3.7V Li-Ion battery as well as a solar battery charger, all from adafruit. I also got a boost converter thinking that the output of the ...
2
votes
1answer
98 views

Steal 5v from USB Module in 3v Mode

My project includes an ESP8266 (runs at 3.3v) and a USB C-Serial breakout. The USB module can optionally run at either 5v or 3v, and there's are solderable jumper pads to make that switch. Here's ...
-1
votes
1answer
86 views

What is happening when I apply 5V DC to the DC end of a 12V AC to DC adapter? [closed]

The question is in itself a little bit confusing but I will try my best. So I have a normal 12 volt (1 amp) AC to DC wall charger, nothing fancy about it. I use that to power a fan, which works great ...
0
votes
0answers
32 views

NodeMCU - Are all GND connctions born equal?

I'm designing a PCB which is based on NodeMCU board in its core. On NodeMCU there are some GND pins, most of them are to serve digital outputs/inputs, or external sensors which operate on 3.3V. Vin ...
0
votes
0answers
140 views

VCA on 5V powersupply

I've made a VCO and ADSR-generator with two Arduinos. The VCO uses a DAC made with a resistor ladder, the ADSR-gen uses a 12bit DAC. Everything is 5V powered (USB charger of 1A). In my search for a ...
5
votes
2answers
249 views

Capacitor selection for LM3940 LDO regulator

My project requires 3.3v for operation. For the simplicity I want to power it with USB sources and this makes me to add step-down converter/regulator to get 3.3v from 5v line (let's omit input power ...
1
vote
1answer
105 views

Using 2 5V pins to get 10V [duplicate]

I want to to my RaspBerry Pi 4 with an old small CPU fan. However it's a 12V fan. Is it possible to use 2 of the 5V pins on the board to total to 10V? Sorry if this is a dumb question. I haven't ...
0
votes
2answers
330 views

How to amplify a 0-5V PWM Signal to 0-12V, 10A

I need a Power amplifier which amplifies a 0-5V Arduino-generated PWM Signal to a 0-12V Signal with 120W, for powering a ZVS induction heater. Linearity is not important because i can correct the ...
0
votes
2answers
82 views

Charging a battery without overloading the rest of the circuit

I have a charger circuit (BMS) V1 which charges my LiFePo4 V2 battery, the battery also attaches to a circuit which can take a little more than 3.3v, however if for what ever reason the battery fails ...
1
vote
2answers
307 views

Why these tutorials don't care about wires when using 10A with 5V to light up strip LEDS?

One popular project I want to do with my Arduino is to light up 150 LED Strip of 5 meters (WS2812B). Here is my project: So, I have a power supply of 5V 10A (ALITOVE 5V 10A AC to DC Power Supply). ...
22
votes
4answers
6k views

5 V home network

I'm planning on adding multiple IoT devices in my house, and I'm looking for an elegant solution to power them all. They'll all need 5 V, a small number of them (cameras) would draw up to 2 ...
1
vote
1answer
155 views

How to power a device using a USB port instead of AA batteries?

I have a device that uses 3 AA batteries and I would like to power it from a USB port instead. As I understand I will have to use resistors but I have no idea on which ones. I have found the following ...
1
vote
2answers
175 views

Best way to connect 5V to GND from ESP (3.3V) - transistor or optocoupler?

First of all: I read through some of the suggested topics (i.e. connecting a 5V relay to an ESP), but to my (limited) understanding, this seems not to be the problem I'm trying to solve. If it is, ...
0
votes
3answers
124 views

How to interface a C64/Atari joystick port with the ESP8266 (level shifting from 5 to 3.3V)?

I'm working on a device based on an ESP8266 (Wemos D1 Mini) that shall be connected to a C64 or Atari 8-Bit computer's joystick port. At the same time, a normal joystick could be connected (signals ...
0
votes
0answers
80 views

Usb charger not charging only with vcc and gnd [duplicate]

I want to charge my tablet on the wall. And I have a charger behind the tablet and connected 2 wires to vcc and gnd, the same pins as usb female, it turns out that I can't have more than 10 mA. If I ...
3
votes
2answers
112 views

Minimum Current(not for switching) On a Relay?

I'm trying to understand how the pictured device works. It's a Sonoff WiFi controlled electrical relay. I was told that it is designed to control mains voltage only, and cannot be used to control a 5v ...
0
votes
1answer
103 views

Can a 5V 1Ch Relay be switched with 4V? [closed]

I have Arduino Mini Pro 5v and need to know if the Vcc will drive a 5v Relay. My Voltage output measure on the Vcc is 4.2v. Will the 5v Relay be triggered?
2
votes
3answers
208 views

Why “Supports 5V VCC operation” appeared in LVC family datasheets?

Looking into the LVC logic chip family I was aure that it is 3.3 V supply devices. One of our fellows also confirms it here. This manual dated 1999 states that LVC is 5 V tolerant (version A), but not ...
0
votes
2answers
258 views

I'd like to run a 5v fan on 2 3.7v batteries

I have zero experience so if this is a stupid question please at least be kind. It seems obvious that I couldn't run the fan on one 3.7v battery but then I'm not an electronics guy. So I was thinking ...
0
votes
2answers
72 views

Solar RC Airplane – Trouble with Mini Solar Lipo Charger

I'm in the process of building a solar powered remote controlled airplane. My general idea was that I have 5V from the solar panels powering the receiver, the ESC, two servos and a brushless motor. If ...
1
vote
0answers
111 views

UPS power supply for both router (12V, 2A) and up board squared (5V, 6A)

I was searching for an UPS (uninterruptible power supply) to power my Up Squared Board (5V, 6A) and my router (12V, 2A). So far I didn't find something suitable but here is my idea: Take a suitable ...
2
votes
1answer
239 views

Help me identify power issues with this PCB

I bought the following UPS module for my Raspberry Pi: Power Pack Pro The module kinda works, when I unplug the power cable, the module instantly switches to battery powered mode without restarting ...
0
votes
1answer
471 views

SMPS 5V without load, fluctuation on load TOP258PN [closed]

I am using PI Expert Online (this) to design a smps circuit for 5V, 2.5A output. I already have TOP258PN IC with me so built circuit for that. Change from schematics: I am not using choke and using ...

1
2 3 4 5
7