Hello all,
just got my first EasyEDA project back from JCLPCB and it’s almost as I envisioned it.
My issue is the under voltage protection. It correctly disconnects the battery but I can still measure 0.7V between Vcc and GND.
My question: how to track down this issue?
I have attached the...
Hello,
I created a project that is using a 328P to drive 24 LEDs (WS2812) which can draw 2A.
I used a guy to make a PCB layout (attached) and ordered an assembled version but something with the boost circuit is not working right. He used a LTC3872 to boost 3.7 to 5 but the circuit runs the...
Hello all,
I have an issue with the 5V input to the Arduino Nano. I noticed that when I power (using a power bank) my Nano via the USB port I get a clean ADC reading from my microphone but using the same power via the Vin pin I am getting noise. This makes me think there is a filter in the...
Hello all,
I would like to know what the maximum PWM frequency would be that I can drive this MOSFET:
http://www.vishay.com/docs/72439/sum110p06-07l.pdf
There are a lot of delay times given but even if I take the highest number (200ns) for 'turn-off time' this would result in 5 MHz. But this...
Hello,
I am having hardware specific problems with analogRead when I am supplying power via the Vin pin on an Arduino MKR1000 (https://www.arduino.cc/en/Main/ArduinoMKR1000) — It’s an Atmel SAMD21.
Attached is a very simple voltage divider circuit that should always return a value around 2047...
Hello all,
I am using PWM in my solar charge controller and by default the frequency is 900 Hz of the micro controller?
with 900Hz you and hear the MOSFETs making noise when not full on. I tried setting the frequency to 9kHz which makes the sound not audible any more.
Is there an optimal...
Hello,
below is my circuit for zero cross detection at 110VAC.
My pcb has 2 of these and they are connected to 2 independent AC sources.
I get a lot of faulty zero crossing events from the interrupt of the Arduino.
Below is the sampled input for 100ms.
At 19ms there is the problem. Vertical...
Hello,
I am looking for an I2C device that can help with accurate measurement of amps (+/- 50A @30VDC) flowing in 2 directions (in and out of batteries). I am currently using an Arduino to do this but accuracy is low in terms of available bits at the ADC but especially with the sampling rate I...
Hello,
I am trying to find out if a design of a residential battery operated AC power source (similar to a UPS) is by the NEC code or if not, how to get it to be code compliant.
The power source requires access to power coming from a renewable energy source - not Gridtie. The line has to run...
I have a question about permits to install an inverter at my house.
I want to put one circuit in my house on an offgrid inverter for backup purpose. I asked an electrician and he told me that this would require a permit.
Is this true? Can someone point me at the official "regulations" ?
Thanks...
Hello All,
I am using a hall sensors (ACS756, 24VDC, 50A bi-directional, link) to build a battery gauge. The problem is the 'zero point' of the sensor. The sensor is fed by 5V and by the specs sheet it should deliver 2.5V if no current is flowing. I am using the analog input of an ATmeaga2560...
Hello,
I am looking for a solid and reliable 24VDC MSW inverter for 120V outputting around 1000W. I own a PowerBright 24V, 900W inverter which does a very good job but I recently recommended that same model to two friends and they both had a very bad experience: one was bad out of the box and...
Hello all,
I am running a few household items with an off-grid inverter powered by solar panels. All is fine except my laptops. When I am using the track-pad the mouse cursor jumps around like crazy. Only if I am holding the laptop case with my other hand it works again.
I think I understand my...
Hi All,
I am looking for an alternative to these cable lugs
On my current PCB design I am using 10 of these in a row (rating of 30V DC with max 50A)
Unfortunately these lugs makes if very hard to design an enclosure and I came across the 'Powerpole PP75' connectors from Anderson Power.
Has...
Hi All,
I have a problem with the relay on a custom PCB I designed. On my breadboard prototype the parts where somehow spaced out enough to not show the problem.
The relay I am using is a DPDT 120VAC (Mouser: 653-LY2-DC24). In 50% of the switching operation, a button is triggered as a...
Hello All,
I am using a DC/DC converter from 24V to 5V for my Arduino project. The converter is producing a high pitch sound that I would like to silence. I am using a TI MC34063AD in the Step-Down configuration on page 8 but coil 330mH instead of 220mH.
Any Suggestions?
Thanks
Markus
Hello all,
I am looking for some guidance for UL listing. I looked at the official UL website but that is totally overwhelming and I got lost almost immediately. My situation is this:
I have created a PCB with an ATmega2560 (Arduino), a 120VAC(10A) relay and some 30VDC(50A) mosfets on it. The...
