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26

No, you should not increase the voltage any further... and at least this answer linked in the question does not suggest to do that. From Raspberry Pi Power Limitations: Power sources SHOULD provide 5±0.25V ... and: The newer Pi(3/2/B+) have a voltage monitor chip (APX803) which triggers at 4.63±0.07V. The Pi3B+ uses a MxL7704 chip to manage power, ...


16

The MAXIMUM is 5.25V, although this should NOT be the target. You should not apply more than 5.1V That is not to say the Pi will be damaged by the higher voltage, because nothing uses 5V - the on-board regulator supplies the voltages used by the Pi. There is a point when the transient protection diode will trigger - causing the poly fuse to blow. No one ...


12

If you want to do it with a shell script, here is a solution that works on Pi 1, 2 & 3 (not tested in zero). With the command: /opt/vc/bin/vcgencmd get_throttled If the answer is: throttled=0x0 You're good with the supplied voltage and SoC temperature. The bits on the returned number mean: 0: under-voltage 1: arm frequency capped 2: currently ...


9

You need to consider that the forward voltage of a white LED is likely in the range of 3.0 V to 3.2 V (according to the linked article). Assuming the best case of 3.0 V and a resistor of 330 Ohms and using Ohm's law R = U / I we find that the current is about 1 mA and thus the brightness of the LED is rather low. Decreasing the resistor will help to some ...


7

I will be customizing another power supply manually using voltage dividers You can't do that. And this suggests that you're a novice with electronics. Voltage dividers are fine for signal conditioning or creating a relative reference point for something, e.g. an A/D converter. They are not a way of regulating a power supply. Any modern computer varies its ...


6

Nobody can answer that question as it will be down to the peculiarities of the components in each Pi. As you know 5V +/- 5% (4.75 to 5.25 V) is the USB spec. In your case I suspect your power supply claims more than it delivers. Try a better cable or known truthful supply. That said I have powered higher at 5.8V without causing any known damage. However ...


6

Use a PoE Hat: Third-party USB-C charging devices can be cheaply wired, potentially destroying connected devices as well as starting fires. A safer alternative is to power your Pi using PoE which beyond reducing these risks, offer additional benefits: Benefits: Using a PoE Hat is easy to setup and enables you to: Emplace a Pi at a much greater distance ...


5

There's two ways to power it. With a USB-A to microUSB cable. Plug that into the USB-A socket on your screen, plug the microUSB into your RPi. Connect your wall-wart power supply to the microUSB on the screen. With two dupont wires, one on pin#2 or pin#4 (connected the the 5V pin on the display) the other on pin#6 (or any other GND pin connected to the GND ...


5

The spec specifically states that: A good quality 2.5A power supply can be used if downstream USB peripherals consume less than 500mA in total. Using a 2.4A power supply with the Pi 4 and a 2.5" HDD is going to be borderline assuming a typical power rating of the 2.5" drive of about 1.8W to 2.7W (see here). From the above statement - after all it really ...


5

The best option is a good quality power supply, as cheap brands may say they are rated at 2.4 amps, when they don't actually supply that much. Based on the numerous bad experiences i've had with 3rd party chargers, i'd highly recommend buying the official one from the foundation! Whether that is adequate for the hard drive is another question. I haven't ...


5

I don't see that connecting pin 40 (GPIO21, aux SPI SCLK) to ground would have any bad effect. Most GPIO are set as inputs. Connecting an input mode GPIO to ground or 3V3 is normal operation and has no bad effect. If the GPIO was set in output mode and set high then it might damage the GPIO if connected to ground for an extended period. I don't think a ...


5

The Pi3B+ can supply up to 1.2A total across the 4 USB ports. See Raspberry Pi Power Limitations. This assumes the Pi power supply is adequate. Whether this would be adequate for 2 SSD drives, depends on the drives. My experience is that the voltage from the USB ports often falls below that required for power hungry external drives, so a powered hub is ...


4

I had the exact problem as you. Found it was not possible due to the form factor of the Pi 3B+ when a PoE Hat affixed to it to fit in the "Smarti Pi Touch" case. Used a PoE Splitter (£9.90 in VAT from Amazon.co.uk) as a workaround. The power from the PoE switch is sufficient to drive both the Official 7" LCD Display AND the 3B+ Best of all, the door ...


4

TL;DR The external hard drive is powering the RPI after you remove the microUSB power supply. This is called Backfeeding. This is not unusual for raspberry pi's. Is it bad for the pi I would advise against backfeeding because there is little protection for the Pi. You would need to ensure there is a stable voltage and current to avoid damage. I would ...


4

This is an exercise in futility! Disabling devices will make very little difference in power usage, which is mainly determined by processor load. About the ONLY device which will have any affect is WiFi. You should consider a Pi3A+ which has lower consumption and no USB hub or Ethernet.


4

You will not find a specification, because there isn't one. The Pi4 has the same power manager as the Pi3B+ and Pi3A+ so the current limitation would be the same (the PMIC is rated at 1.5A). The Pi3 regulator is rated at 1A and has been tested at 800mA (on 3.3V). There is no polyfuse or limitation on 5V, so you could in principle draw up to the limit of ...


3

Simply no. The only way to prevent boot is to pull the reset pin (labelled RUN) low.


3

This is the solution I ended up with: Raspberry Pi 1 + 3.5mm headphone jack out Adafruit PAM8302A ("Mono 2.5W Class D Audio Amplifier") Power supply to PAM8302A from RPi Pin 4 ("5V Power") Ground to PAM8302A from RPi Pin 6 ("Ground") 3.5mm cable cut off (plug goes into RPi, one mono pair goes into PAM8302A) Output pins from PAM8302A go to speaker The ...


3

This question has broad applicability to all outdoor use of a Pi, so I will cover it quite expansively... Although possible to use a USB powerbank, as @goldilocks notes, batteries will have to be changed frequently and if the goal is to monitor nature without interfering with it, going to the birdbox frequently to change batteries will disturb the birds, ...


3

Feed both sources to a single voltage regulator through diodes. Additionally, provide a GPIO signal from accessory source which will tell the RPi whenever accessory power is present, so ther RPi can decide to shut down when it's not. Use a timed relay to cut off mains power after accessory power was missing for a minute or two. simulate this circuit – ...


3

I did the exact same thing: Shortened the 5V and 3V3 rail by accident (with a probe). In my case it was sufficient to replace the Power-Management-Chip, which is indeed available. I used aliexpress to order it (MXL7704-R3). You will however need a hot air rework station. A cheap one as in my case will do, but a simple hot air blower from the hardware ...


3

How can we tell apart 3rd party chargers that would work with RPi4? You can either rely on reviews or ask the seller and take their word for it, or you can get the supply, test it, and return it back if it doesn't perform. Obviously, in the latter case you'll want to buy it from a place where you can return it for free. There is no way to tell from the ...


3

The Pi has 3 "components" the CPU, GPIO and Video Core which are relatively independent. Even when the Pi is shutdown the Video Core continues to run, and the GPIO pins retail their state; only the CPU is not running. The 3.3V is supplied by separate circuitry and will be present while ever the Pi is connected to a 5V supply. The best way to reliably ...


3

Question For connecting two USB SSD/HDDs, does an Rpi USB Hub need any external power? Short Answer I measured the idle current and write current of a 1TB SSD, and a2TB HDD. SSD's idle current is 0mA, and write current around 180mA HDD's idle (spinning) current is 170mA, and write current 200mA ~ 380mA My conclusion is that for hobbyist's ...


3

As far as I know, you can not disable only one USB. When you turn USBs power off, also the Ethernet port turned off. I don't know if there is a way to disable USB/Ethernet in config.txt, but in cmd line you can do it with: echo '1-1' |sudo tee /sys/bus/usb/drivers/usb/unbind To enable the ports use: echo '1-1' | sudo tee /sys/bus/usb/drivers/usb/bind ...


3

not able to power ... from a Raspberry pi 3 Here's why: Pi 3 was designed with USB 2.0 specs, including the 0.5 amp limit. Most hard drives require more current than that. Raspberry Pi 4 has USB 3.0, which means it is designed to supply up to 1 amp. That is likely enough to run the hard drive.


2

The above answer (goldilocks) is correct. I just wanted to add the steps without having to navigate to another site. In the Pi terminal: wget https://raw.githubusercontent.com/adafruit/Raspberry-Pi-Installer-Scripts/master/adafruit-pitft.sh chmod +x adafruit-pitft.sh sudo ./adafruit-pitft.sh Choose your correct screen size Choose rotation (this can be ...


2

What happens during a brownout is not "physical damage" in itself, rather, digital devices start to behave erratically when underpowered. This can indeed result in physical damage too: if the SoC accidentally reconfigures an input pin as output, it can create an internal short circuit and fry the pin, the SoC itself, or an external device connected to that ...


2

What you need is something similar in function to a "voltage divider". And many ways of implementing it, eg using "Opamp". A good intro to Opamp is here: https://www.youtube.com/watch?v=kqCV-HGJc6A And here is a setup using Opamp (Vin is your GPIO, and Vout is 14V) More references: http://henrysbench.capnfatz.com/henrys-bench/arduino-projects-tips-and-...


2

No. USB ports can only supply 500mA (maximum); many adapters less. The Pi needs more current to run reliably.


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