# current

1. ### I want to learn thermocouple type k,j etc,

Hello evryone, I start studying Eletrical and computer engineering and I want to learn thermocouple type k,j etc, however I've been searching and I can find to measure temperatures is using water bath 0° in cold junction so voltage will be the same as thermocouple tables on google, however...
2. ### Current levels of headphone output and PC mic input

Hi there, I am working on a circuit which would allow me to connect a headphone output to a pc mic input. When asking for advice about the design a question came to mind (thread can be found here if anyone's interested...
3. ### High precision 1mAmp current source

Hello, I am looking for a 1 mAmp DC current source circuit design with 0.02% precision to be used in a 5V power supply circuit board and a 3KOhms load. Any suggestion/direction would be helpfull. Thank you all.
4. ### Current limiter for fan

Hey, I'm am trying to use computer fans for other purpose, I tried hooking one up to a 12v power source and it blew up. The fan was rated 12v, but 0.37A and I used a 12v, 2A power supply, I thought the fan would use only the current it needs, but I was obviously wrong. So my question is can I...
5. ### What does the datasheet say about the relay?

I'm busy with a project that uses a Raspberry Pi zero and a relay. I've tried 2 relays and neither worked. I'd like some help to understand how to choose the correct relay, as well as which one will work. First, I used this one: SSR-100DA. I connected the input to the Pi, and the output to my...
6. ### Understanding noise RMS and picking an appropriate current source for Hall probes

Hi Everyone, I am trying to define the most suitable current source for my application. Essentially, I need a high stability current source to feed Hall probes sensors. The probes' nominal current is 10 mA. A stability of 100 ppm (i.e., 1 uA) for short term (a few hours) is desired. Usually, I...
7. ### Inductor current

An inductor of 10H has 1omh internal resistance. What is the current through the inductor after 10V is applied for 1 second?
8. ### Current dependant load switch, cant solve it passively?

Hey there, i couldn’t fall asleep trying to solve following scenario: i have two power supplies running 24vdc in parallel, a main and one supplemental power supply. Both are being filtered with capacitors before supplying a single load. Now if one wants to run it, such that the supplemental...
9. ### Very new to this. If I were to make a DC Motor shaft with cogs and gears circuit, how would I know the required ampage of my power unit?

Very new to this so bare with. If I were to make a DC Motor shaft with cogs and gears circuit, how would I know the required ampage of my power unit (im thinking, battery AA holder). And are there any pre cautions I should take to prevent damage or potential fire hazard? I roughly know about...
10. ### wiring an arducam with the power line on a transistor

I've set up an arducam mini 2MP plus with a nrf52DK (similar to an arduino for this set up) to take pictures. Ive got the board and camera working when the camera is wired with the VCC line and GND wired directly into the boards 3.3v line and ground pins. The arducam uses about 100 mAmps when...
11. ### Inductive Power charge simulation current control

Hello everyone, I am writing to ask about how can I control de currents in my inductive charger more specifically the current in the resonant tank I designed. My goal is to design an inductive wireless charger that uses a resonant tank to maximize the efficiency of the process. I am going to...
12. ### Voltage Magnitude, Phases, Current for Bus (Load Flow)

Say there are 3 buses of: Bus 1: Slack bus with a voltage source of E=1.0 and phase of 0° Bus 2: a generator and a load. Bus 3: a load. The line impedance are given below: z12 = 0.05 + j0.1 z13 = 0.02 + j0.05 z23 = j0.05 z11 = -j100 z22 = infinity z33 = -j40 The generators and loads are given...
13. ### How to calculate the current of a circuit if a resistor is placed with load in series?

Assume we provide a load with its rated voltage, suppose it should draw the current it need at such voltage level. However, what if we place an additional resistor in series with the load, can the load still draw the same current as it needed?
14. ### Basic Question NMOS Gate Leakage

Hello, I'm not quite sure about the specification of Gate-to-Source Forward Leakage (I_gss) given in many datasheets of MOS-FETs. I researched its definition and it seems to be the leakage current (for specific gate-source voltage), that flows from gate to source, while drain and source are...
15. ### Questions regarding Function Generator - AFG3000C

I am having this new Function generator - AFG3000C I am having difficulty in understanding certain terms related to this FG. I have tried online searches, but I couldn't get what I was looking for. Being a newbie, I request you all to help me understand my queries in simple terms. Could you...
16. ### XML T6 LED DRIVER MODIFICATION

Good night. I bought this flashlight for my bike: https://www.ebay.es/itm/Luces-Bicicleta-Luz-10000LM-Impermeable-3XT6-LED/292872854958?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 But the light that comes out seems very little to me. I think it has more potential. Could I modify...
17. ### Max fan current from MB in Samsung TV

Hi, I need to replace the fan in a Samsung TV but not sure about max amperage on the MB fan port. The original one is 12v and 70mA but I can't find a like for like fan. Need to improvise. I have a few candidates with similar mount and CFM and on 12v but at 100mA or more. The MB is BN40-0012A...
18. ### current measurement over time

I have a RC servo towerPro sg90 connected to Arduino, to measure the current I have put 1 ohm shunt resistor between servo GND and power ground. Then I did a analogRead on the resistor, when servo sweep between 0 -180. I am getting following values out of my analogRead. So in total I have 180...
19. ### Slayer Exciter using darlington pair

Hi guys, this is my first post here. I hope I'm in the right section. I've made a slayer exciter with a 22kohm resistor, a 2n2222 transistor, using a 9v battery. My secondary is 0.25 mm and 10 cm in lenght. My primary is 4 turns. I wanted to obtain some sparks, and I added a 47k instead of 22k...
20. ### Theoretical values for ”natural frequency”, currents and voltage at electrical resonance.

I am supposed to calculate the theoretical values for ”natural frequency”, currents and voltages at electrical resonance for this circuit. I should use the measured values for the resistance and the inductance of the coil. Also the measured value of the capacitance to the capacitor. The...