voltage regulator

  1. U

    How to use transistor as a variable Regulator?

    I'm designing a variable power source from 5V to 30V with 600mA. Input voltage is VIN = 36V. I tried the below circuit. VREF is given from microcontroller DAC. I tried using N-MOSFET, P-MOSFET, NPN, PNP (with modifications). I set a the output voltage as 20V. This circuit works fine with no...
  2. E

    Voltage regulator for battery powered microcontroller

    Hi folks, I think what I have is a fairly simple question, yet I've spent so much time Googling, that I've completely lost track of what is what. I'm looking for an affordable voltage regulator to power an ESP32 from a number of AA or AAA batteries. I have bought a pair of these (Dutch...
  3. J

    Noise reduction connecting PCB to USB

    Hi! After producing multiple different PCB designs of a board for controlling a stepper motor, I noticed something that I cannot explain. The boards are in general powered through 12 volts, then a voltage regulator brings the voltage from 12 to 5 V and another one from 5 to 3.3 V. Stepper...
  4. T

    how to get approximately 30V on Vout in this voltage source?

    hello everyone. i´m doing a voltage source and i want to get approximately 30V-500mA on Vout with the smallest ripple as possible. : i got a transformer 12 0 12 V and a 1000V 2A bridge rectifier and 4700uf 35V electrolytic capacitor. The thing is: after rectifying it it should give me 24 *...
  5. Bogdan_Ionut

    How to I know if an electronic component works with AC?

    I need to know if LM2596T-3.3 voltage regulator works with AC electricity. Datasheets doesn't specify the type of current.
  6. L

    LM317 no reference voltage

    Hello all, This is my first post so forgive me if I break any rules, I am trying to create a variable voltage power supply using an lm317 but am running into problems. For starters, it doesn't seem that I have a vref voltage, when probed I get 0 volts across input and adjust. My second problem...
  7. laythrom

    Trying to wrap my head around designing a (simple) LED circuit...

    Hello all, I'm trying to make a PCB for a LED-based lighting panel and I'm trying to wrap my head around the best way to layout the circuit. After a decent amount of scanning through the web, it seems like using voltage regulator(s) is a better way to go over the old LED array with resistors...
  8. W

    Converting 1.5V from AAA cell to 0.8V output

    Hi all, I'm designing a circuit that needs to take 1.5V from two AAA cells in parallel and outputs 0.8V to a DPDT toggle switch (on-off-on) that connects the load to +0.8V, 0V, and -0.8V depending upon the switch position. The output current would ideally be able to reach up to 1.5A for safety...
  9. M

    idea needed for a simple, automatic voltage regulator for 3V LED

    An idea needed for a simple, automatic voltage regulator for 3V LED. The application is for an electric model train (HO) which operates on 0V - 16V DC power supply. Traditionally, these locomotives utilise a 12V micro lightbulb which changes brightness in line with voltage applied to track...
  10. A

    Basic Inverter Voltage regulation

    Hi! I copied the DC-AC circuit from here, or specifically speaking this image (I didn't used the diodes because I think they are useless in described configuration). However when I observe AC voltage using DMM, I get the following results: 1. 5W LED bulb with capacitor shows voltage 37.4V 2. 5W...
  11. V

    problem with variable voltage circuit development.

    Hello, Thanks for your support in this forum. Currently, I am working on a project in which the operating voltage is 12v 1.5A to be given to the circuit. but, my input power supply varies from 12v to 24v of 2.5A. but I am not getting an idea that how to get constant voltage regulation of 12v...
  12. jcarlson023

    DC Switching linear regular design question

    Hello, I am fairly new to electronics design (I have a mech e background), and am designing a board that requires dropping 12v to 5v with a large current requirement (up to 8A@5V). In a bid to save on BOM, I took a shot at creating my own design vs buying one off the shelf, using the...
  13. E

    ALternative to regulator MST5333BTG

    Hi i have one board which has this regulator which i am not getting nearby market. I am looking for alternative to MST5333BTG regulator.
  14. bignobody

    First time using a Voltage Regulator sanity check, plus decoupling capacitors questions

    Hi! I've only soldered a few circuits before. Tomorrow I am planning on building a mono audio amplifier with a LM386 IC. I've a thread about it here (including a link to the schematic I am working from) https://forum.allaboutcircuits.com/threads/166673 The schematic uses a 9V battery, but I'd...
  15. G

    lm317t output stays about .7v lower than input

    I've got a bunch of these and they all behave in the same way, so I'm doing something wrong. I'm using the output calc and schematic here: https://circuitdigest.com/calculators/lm317-resistor-voltage-calculator I'm trying to get it to near it's minimum so for R1 and R2 I'm using the same value...