Questions tagged [linear-regulator]
A linear voltage or current regulator provides a continuous non-pulsed supply of current or voltage. It may be fixed or adjustable, and can be put under control by a CPU/MPU. In spite of sometimes low efficiency they are popular because they provide clean noise-free DC current or voltage, as opposed to switching supplies that can be very efficient with power regulation but induce much RF noise into the outputs which need extra parts to filter out.
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Using Linear Voltage regulators in parallel for a high current load
I need to build a high current 12 to 5 volt regulator.
This will power neopixels, which draw 60mA each, and we have like 800 of them, so around 48A when all of them are on at full brightness and white....
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Should I consider using two Switching regulators or one switching regulator and a linear regulator
I have a circuit that has an input of 24VDC. The circuit has two different voltage rails requirements. 12VDC @ 0.1A and 8VDC @ 1A. I have decided to use a swithching regulator from 24VDC to 8VDC, and ...
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LDO stability with resistor in the feedback path
I am working on a circuit for measuring very low and very "fast" currents (think: measuring power consumption of an MCU). I found out that I can measure what I want with a sense amp and a ...
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Why is my 5V linear regulator giving out 6.34V?
Update :-(:
I tested the pinouts of the IC with a multi meter and the connections are fine. Then I discovered I had done a very stupid mistake and connected Vout where Vin should have been connected. ...
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How to make fast CV/CC transition in linear NMOS regulator?
I want to design a linear regulator based on NMOS with CC/CV capability. I made a circuit with two separate loops (CC and CV), each of which is stable. The problem is in the transition moment when the ...
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Vintage LM317T Linear PSU Improvement Suggestions
Recently I came into possession of two very old linear PSU devices from 1993.
I replaced the caps and tested the devices and both work. I have been using them in conjunction with 12 7Ah lead acid ...
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LM337 Unstable regulation
For an audio project, I need a low noise +/- 12V supply.
I have a linear power supply of +/- 15V and I decided to use the LM317 and LM337 to decrease the voltage to 12V.
The circuit that I use is the ...
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Should I be skeptical of a component when its datasheet specifies a specific type of capacitor?
I'm researching 5V regulators for a project and came across one that looks promising, but I noticed that its datasheet specifically calls for a tantalum capacitor on its output. Normally I wouldn't ...
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Overshoot on dc/dc converter
Any idea on what would the level of overshoot that this LDO can provide?
Would that data/information on overshoot would be provided in the datasheet? If not, how should I understand that?
I am using ...
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Connecting linear regulators in parallel
I have seen some images in which two linear regulators of the same type (basically the same part number) have their outputs tied together. I believe this is being done to increase the total current ...
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Preventing Op Amp oscillation in PNP Linear Regulator Supply
I am currently designing a PNP-based linear regulator (see images). However, I am having trouble with it oscillating.
There is a sizable 200 mV saw wave oscillation at its output. No, it's not power ...
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Grounding Circuit with two Power Supplies Wired Together
I am trying to operate an x-ray tube that requires a high-voltage supply and a lower-voltage filament supply.
The high voltage supply consists of a Cockcroft–Walton voltage multiplier, and the ...
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Determining feedback resistors for the BD00FC0WFP LDO voltage regulator
I'm trying to configure the regulator to output 4.5V. From what I gather, the output voltage is governed by the voltage divider between Vo and GND where the device's FB pin reads the voltage dropped ...
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What is the highest practical bandwidth of a linear voltage regulator/LDO?
I am trying to evaluate what the highest pratical bandwidth of linear regulator/LDO is. To be more precise, I am looking the bandwidth of the transfer function Vout/Vin.
I think the bandwidth is set ...
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Shelly Uni IDC with a potentiometer as a garage door open sensor (percentage) - voltage regulator with low current
first of all, I'd like to mention that I'm not an electronic engineer (done some ESP8266 and Raspberry solutions, but mostly by using ready-made components and shields), so if some info is missing or ...
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LP2951 external transistor
I want to use LP2951 reference design from ONsemi datasheet (picture below). I'm not going to build the current limiting section of the schematic because the device will have external overvoltage/...
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High voltage MOSFET linear regulator failure
I designed the circuit below for an FSAE electric vehicle, for which the rules require an HV-powered LED to be lit when the HV bus is above 60 V. In simulation, the circuit works very well.
In real ...
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Linear regulators in series [closed]
I'm helping a friend review a schematic. It's a battery-powered project with three rails: battery (AAA 3 x 1. 5 V) and two linear regulated rails (LP5907MFX-1.8 and LP5907MFX-3.3). The 3.3V reg is ...
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LM317 current regulation below 20mA
I made small regulator which is supposed to deliver from 20 mA to the exact lower limit of LM317 for current regulation in self-biased mode.
The question is, the LM317 datasheet says it's rated 10 mA ...
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What happens when a resistor fails?
simulate this circuit – Schematic created using CircuitLab
I am trying to test my LT 3083 voltage regulator using a chip resistor to model the load. My input power was 5V and I was trying to ...
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Power Good Connection for Regulator Sequencing
For powering Artix 7 FPGA I need power sequencing. In the Artix-7 data sheet it states that the recommended power-on sequence is VCCINT (1.0 V), VCCBRAM (1.0 V), VCCAUX (1.8 V), and VCCO (3.3 V). ...
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Unknown "JE07" SMD SOT-89-3 Regulator
Can someone please help in identifying what this "JE07" SMD is? All I know is that 28V goes to the tab of the sot-89-3 smd part which is also the middle pin. I assume that is the input pin. ...
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What is the simplest way to adjust the input voltage for a linear regulator?
I have a garage door opener for which I need to replace the radio receiver. The opener outputs a DC supply voltage for a receiver at 34 VDC. The receiver has an input range specification of 12-24 V AC/...
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Linear regulator thermal information missing in datasheet
I'm considering to use UA78M33CKVURG3 in my design, so as with any linear regulator I have to make sure it will be able to handle the current draw in the worst case scenario. To calculate what the ...
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Why is this regulator circuit unstable?
I'm trying to use a LDO with higher current (5 A in my case) than what it's rated for. I derived for this the following circuit
V is a noisy voltage source between 16 and 22 V (mainly 50 Hz 1 Vpp ...
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Optimising standby current of battery operated designs with momentary power activation - circuit example from digital level
My digital level flattened its 9 V battery within 2 weeks of little use, so I measured its standby current which came out at nearly 2 mA!
I took the cover off was shocked to see the battery connected ...
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Parallel split rail supply with only positive regulators
I'm designing a +/-12V split rail supply for a eurorack (modular) sythesizer. I was adviced to put a pre-regulator block at a higher voltage a connecting to it several point-of-load regulators. ...
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LQR Infinite Horizon vs. Finite Horizon vs. Receding Horizon?
I don't know if this is the right forum, but I would like to know in words the difference between these 3 forms.
I have searched online and in books but there are often demonstrations packed with ...
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How can I power an ESP32 with a 54V battery using a buck converter?
I need to power an ESP32 board from a 54 V battery. For that purpose, I understand that I need to step it down to 5 V so I need to design a step-down buck converter.
I tried the following circuit ...
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Selecting the current rating of a LDO linear voltage regulator
I'm prototyping with a development board which has a 3.3 V rail and I have an IC that needs to be partially powered at 1.9 V. From my research, LDO linear voltage regulators are ideal for this ...
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Input current on linear power supply
I am working on a new project, and I need to build a big PCB with a lot of circuits integrated. Therefore, I need to make a power supply on the PCB.
Since I am not comfortable with SMPS design, I ...
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Ripple rejection of capacitance multiplier when compared to linear regulators
There are some posts and discussions how a circuit popularly called a “capacitance multiplier” could reduce low frequency ripple noise (at 50/60 Hz or 100/120 Hz) and could perform better than common (...
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Kirchoff's voltage law with a LM317 voltage regulator
I'm currently trying to write out Kirchoff's voltage law loops for a LM317 voltage regulator circuit in order to derive the equation Vout = Vref(1+R2/R1) + (I_Adj * R2):
However, I'm currently stuck ...
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54 V to 5 V using LM2576HV
I have a requirement to convert 54 V battery output to 5 V. My battery's positive terminal is grounded. I tried the connection as mentioned in the datasheet which is attached here, but as soon as I ...
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Darlington Pair TIP41C at op amp output not amplifying current
I am trying to make a variable voltage regulator with the TL081CP op amp. When I add a single TIP41C transistor the max current I can get at the 20 ohm 20 W load is about 625 mA.
But when I want to ...
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Voltage regulator not heating up ... How?
I connected a L7805 to a water fountain that I measured to be consuming 0.1 A at 5 V to regulate power coming in from three 5 W, 12 V solar panels connected in parallel.
The regulator is not heating ...
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LDO - Need more current: build a discrete regulator?
I'm working on a battery-powered device using an ESP32. It needs 3.3v, and my battery is Li-Ion, so I've got 4.2-3.5ish (of useful voltage, anyway) - so max dropout has to be around 200mV. Most of ...
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Thermal shutdown feature in an IC
I'd like to understand more about thermal shutdown in an IC.
I have read that, if the IC junction temperature exceeds beyond a certain limit, the IC shuts down itself which is known as thermal ...
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Improving/fixing and condensing a variable 0-1A 0-20V 25W linear power supply circuit design
So, in a previous a previous question I was trying to come up with a way to set up a voltage control block for a dubiously specified voltage controlled power supply. I've since come to a working ...
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Common high power diode driver architectures?
I want to design a circuit to drive a noise sensitive, high power (~2A @1.5V), laser diode. What are the most common drive architectures that commercial laser companies use? Buck converters, linear ...
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Are all linear regulators adjustable?
Some linear regulators are marketed as "adjustable", but all linear regulators create a specific voltage in relation to their ground pins. Since the ground pin voltage can be offset from the ...
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Using a series regulator to produce a control signal for a voltage controlled power supply
Edit 2 starts
So I have a full circuit, though it has a critical problem: it's utilizing too much power, so the power line is unable to support the circuit. For simulation's sake I used DC power to ...
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RP400N501A DC-DC regulator on PCB not outputting correct voltage
I have created a PCB that is powered by a 3.7v lipo, and has a 5v boost converter and then a 3.3v linear regulator. The reason for the 5v boost converter is that I have to drive some LEDs at 5v, but ...
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Can linear regulators be divided into series and shunt linear regulators?
I was reading a linear regulator tutorial and found this.
It is very different from what I read in books.
As compared to LM7805 (Fixed Voltage Regulators)
YouTube link.
Source: Freescale
Both are ...
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Linear regulator and switching regulator terminology
Linear voltage regulator = linear regulator = voltage regulator?
Switching regulator = switching voltage regulator = switch mode power supply SMPS (e.g. step-up, step-down)?
Are the terms above ...
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54 V input on one, or two 40 V linear regulators? (LM317)
Before I explain the situation I am in, please bear in mind that I am completely new to electronics, and I want to spend as little money as possible on my current project because of outrageous pricing....
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LM7805 decoupling capacitors
Would it be possible to replace these combinations of ceramic and electrolytic capacitors with just a pair of low-ESR 10 μF ceramics?
Conversion from 12 V to 5 V, minimal consumption, only MAX485 ...
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Does PSRR improve with multiple LDOs in series?
Would having multiple LDOs with different output voltages are in series, for example: 5 V from a buck converter -> LDO1 (3.3 V) -> LDO2 (2.8 V), and assuming all LDOs satisfy the dropout voltage ...
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Voltage regulator output increases significantly when step-up converter runs
I'm using the LTC3108 step-up converter to charge a supercapacitor from a thermoelectric generator. The output voltage drives a 1.8V regulator (S-1318) which is enabled once the voltage reaches 4V (...
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Op-amp error amplifier protection in tube amp high-voltage shunt regulator
Check out my latest contraption, a B+ regulator for tube amps, adjustable from 200 to 300 V. The error amplifier/shunt MOSFET bias servo op-amps are fed 5 V from a 7805-based external board placed ...
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