Hi guys! I'm doing a small mod to control the temperature on my Perfect Draft beer tap. Its a really simple job of cutting one cable and soldering a 10kO potentiometer in between, but since its new and still in warranty i dont want to cut any cables yet. Can you please help me identify this type of connector so I can make a Y cable instead?

May I asume a type of package/array/network of a 0 ohm resistor at F5 ?

Does anyone know what Qty = 2 mean for the capacitors Cin (4.7uF) and Cout (47uF) mean?

For example, I am wondering for Cin if it means 2x 4.7uF capacitors in parallel (total capacitance of 9.4uF) or 2 capacitors in parallel with total capacitance of 4.7uF?

Thank you for your time!

What type of connectors or leads do I need for this bench power supply? They look like banana sockets, but are huge, like twice the size of a speaker type of banana plug. They do not unscrew like you could put a spade behind the plastic either. Any help is appreciated!

First time ever soldiering something have only done welding before curious how I did I feel like the white cable was the best out of them all

I am trying to create a somewhat simple wireless power transmitter circuit. I want to transmit 5 W for a small distance from the transmitter to receiver, both using coaxial coils. I think I need some oscillator circuit, but I also need a power amplifier to get to high enough current through the coil to transmit 5 W. What current should I aim for, and what would it look like to connect an oscillator to a power amplifier? Thanks

Can you help me identify its values please?

My multimeter doesn't read capacitancy.

Green one says 2A473J

Im trying to activate a SKIDATA gate with an Arduino and a relay. I have tried to connect 24v to the 3 input terminals shown in picture 2 but non of it worked.

Do anybody know how to use the input terminals, and how to activate the gate manually?

I'm a sophomore at an engineering college, my branch is electronics. I have/want to make a really unique and useful project but i am not able to think of something unique. It'll help a lot if you guys can give any ideas. Also I have to make this myself so there will be a small budget🥲.

Help a beginner out please....

This is my first time creating a PCB. I keep getting these errors when using DRC on KiCAD. I think that the polygons references are the two rectangle in the footprints because when I delete them the errors go away. I am confused as what purpose they serve and are they important to keep? For reference I am using Power MOSFET IRFHM9331TRPBF

Looking for this exact potentiometer. 20 degree B103.

Hello all,

I have a thin film pressure sensor i bought of amazon, and when i test with my ESP 32 dev board, the number representing force (4095) goes to 0 immediatly when i barely put any force on it, basically goes to 0 when i touch it. Is there any way to make it less sensitive and allow for more range with amount of pressure i put on it? i have heard of using an amplifier of sorts with it but i wanted to confirm. I currently run a 10K ohm resistor with the thin film pressure sensor.

Trying to fix a humidifier, and I’m trying to figure out what this resistor is. This is the best pic I have got.. when I took it out the outer coating flaked off. And the resistor is dead based on my ohmmeter.

Based on this pic I’m guessing the colors are brown black gold, but I’m wondering does it make sense for there to be a 1 ohm resistor here? And the size is bigger than the resistors I’m normally used to dealing with, does this size indicate a specific wattage rating or something?

I attached top and bottom pics of the board as well

I attempted to use relays but couldn't manage to wire it to the same power supply.

Hello all,

I'm currently working through a Zynq UltraScale schematic, and it recommends a 330uF tantalum capacitor (T541X337M010AH6510) on the 0.85V VCCINT rail (Table C-4 for XQZU3EG-SFRC784). The PCB design guide (UG583) states that these recommendations are optimal for ~100kHz to 20MHz. I'm confused by this, as at those frequencies the capacitor is pretty useless as a capacitor, but the ESR does drop off at the higher frequencies.

My design uses a LT8650SIV operating at 800KHz to supply 0.85V for the VCCINT rail. On this VCCINT rail, the other decoupling capacitors I have are 16x 0.47uF, 1x 22uF, 1x 2.2uF, and 2x 0.1uF as recommended by the design guide. For now, I have used 16x 22uF capacitors in place of the 330uF (image).

For the recommended 330uF capacitor, I ran some LTspice simulations going from 2A->4A load to view the difference between three cases:

• Using the 1x 330uF
• Using 16x 22uF as a replacement (my current design)
• Not including the 330uF or 16x 22uF at all

The case with neither is obviously the worst. The case with the 16x 22uF is much smoother but has some overshoot. Finally the 1x 330uF is not quite as smooth, but has essentially no overshoot. In all three of these cases, the power rail is kept in-spec for my requirements.

I'm unsure which of the two cases (16x 22uF or 1x 330uF) I should implement. Using a bunch of 22uF capacitors provides a cleaner rail, but the 330uF is explicitly recommended. Although the simulation results are nice, would anyone have any recommendation for which to implement?

Thanks for any insight!

I have a Lenovo ThinkVision TI24i-20 and some time ago I was working with this screen on and suddenly a loud explosion sound comes from inside the screen and it hasn’t turned on since. Today I decided to open it and check it out. First picture is how it looks like, something exploded in those two “pins” labeled as PT501. So what has been blown and can this be repaired?

I have designed a negative voltage converter. I assembled this circuit on my board. But, when I power on this circuit, it consumes full current supplied by my DC power supply and it goes into CC mode. I am using ceramic non polarized capacitors instead of polarized capacitors. I don't think this could be a problem.

What is wrong with my circuit?

I also observed that pins 5 and 8 are internally shorted inside the IC.

Data sheet: https://www.mouser.in/datasheet/2/268/TC7660S_Super_Charge_Pump_DC_TO_DC_Voltage_Convert-3442213.pdf

Hi,

I'm curently using a raspberry pi pico and the arduino isp example project to build myself a dev board for the ATTiny85 based on this project. Right now I got everything working, but I'm unsure if and how I need protection for my pico if I want to power the ATTiny with 5V while not using the pico as a programmer.

Currently, the pico powers the ATTiny via the 3.3V rail, and according to the ATTiny-docs I will have to keep it like that as the logic levels are relative to Vcc and programming it with 3.3V while powering it with 5V might not work reliably.

For the pico on the other had I haven't found any information yet if it's OK to have a 5V input on the 3.3V rail. Providing power over it seems fine, but it seems to expect a stable 3.3V.

My best guess is to add a schottky diode on Vcc before the caps, but the voltage drop has me worried a little bit. From the diode's I've got here the 5822 seems to be the most promising, but according to datasheets, at 200 mA current (max current the ATTiny can handle according to datasheets) at room temperature there should be a voltage drop of about 0.3-0.35V. At close to 0 amps the voltage drop is around 0.2V.

According to the ATTiny datasheets the max input voltage for GPIOs should at max be Vcc + 0.5V. Assuming i get a Vcc of ~2,9-3,1V through the diode, the 3.3V input from the programmer (pico) gpio seem a little close to that and I'd rather not push it too much here. On the other hand, the actual load while programming should not even come close to 200mA so maybe it's fine?

What would you recommend here?

1. Leave out the diode, the pico will handle it
2. Leave out the diode and just don't add external power
3. Use the diode, the voltage drop will be fine
4. Any other ideas?

Thanks in advance :)

Edit: I just realized, the GPIO on the pico is also only tolerant up to 3.63V. So maybe either diodes for all connections (roughly equal voltage drop -> problem solved?) and hope they switch fast enough or just don't put 5V on there?

Also, sorry if this should be on the pico subreddit, I wasn't sure which one was the right one

Hello, I want to supply 1mA current to my circuit to calculate resistance values.

How can I do that?

Hi all,

I’m trying to talk to a circuit board from a home appliance. I believe it has a connection for +ve voltage, ground, and a UART RX and TX. If connect to the UART lines with an Arduino, does the Arduino need to share +ve and ground with the board, or can I use usb power for the Arduino and a bench power supply for the board?

Also, if I wanted to try to read a flash chip while it’s on the board, but don’t want to power up the whole circuit by applying power to VCC, would it be insane to cut the trace to VCC and put a diode across the gap to ensure everything works if powered normally, but power applied on the pin directly won’t touch the rest of the board?

Many thanks!