Questions tagged [rectifier]

These are part of AC to DC conversion. A half-wave rectifier keeps only the positive part of the signal. A full-wave rectifier also keeps the negative part, but flips it to make it positive too.

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7
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3answers
102k views

Full-wave bridge rectifier with capacitor filter and ripple voltage

According to various sources, the ripple voltage of a full-wave bridge rectifier is $$ V_r = \frac{V_s}{2}fCR $$ where \$V_s\$ is the peak of the input voltage source, \$f\$ is the frequency, \$C\$ ...
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6answers
24k views

How to convert AC to DC

I am designing a circuit that needs to output 5VDC @ 1A. I'm trying to use a wall transformer to step the voltage down to 12VAC. The next step is the diode bridge and ripple capacitor. The ripple ...
18
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5answers
32k views

Is full wave rectifier better than half wave one?

I am curious if there are practical differences between a DC power supply based on a half wave rectifier or a full wave rectifier. I mean I have a few small DC power supply units which should give ...
12
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4answers
56k views

if a standard three-phase 400V AC connection is rectified what DC voltage comes out of it?

If a standard (in Europe and a large part of the world except North America and Japan) three-phase 400V AC (three lines having 230V RMS voltage if measured to neutral each) mains supply is rectified ...
3
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2answers
7k views

Precision high speed peak detector

As a follow-up to my previous question, where I seek to determine the amplitude of a 2 MHz sine wave, I've settled for an op amp based solution. To recall, my input has a maximum 240 mV amplitude -- ...
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4answers
20k views

Half-wave rectifier and RMS value

I have built a half-wave rectifier with a 5V peak sine input, 1kHz. In theory the RMS of the output should be 5V/2 = 2.5V, but the oscilloscope only measures 2.01 V. What could be the reasons for such ...
3
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3answers
22k views

why do rectified voltage boosts after adding a capacitor?

So I found this 9V 1A AC power supply laying around and decided to make a DC source. I rectified and added a capacitor to make things a bit even. After adding a capacitor my voltage boosted from 9V ...
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2answers
10k views

Serial capacitors in electronic ballast of a fluorescent lamp

Recently I repaired one broken electronic ballast of a linear 30W fluorescent lamp. Now it seems to be working as expected, but I had to make some changes to it and I'd like to ask if you see any ...
4
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7answers
2k views

Bridge Rectifier Fails When AC Inputs are Shorted

I am working on a design that involves powering a 3.3V microcontroller off a doorbell transformer but I am running into an issue with the bridge rectifier failing when the AC inputs to the rectifier ...
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2answers
254 views

High voltage power supply

We are given this schematic diagram, that our teacher called a high voltage power supply, then test the voltage of each capacitor. Why is the voltage at C1 half of the voltage at C2 and is the ...
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6answers
13k views

How does this rectifier work?

In a car battery charger, I found a strange rectifier. Can someone explain to me how does it work? Here I have a transformer which is unmarked. By measuring resistance between its output terminals, ...
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3answers
3k views

Simple \$12V_{AC}\$ to \$12V_{DC}\$ Rectifier

I want to convert a \$12V_{AC}\$ power supply output to use \$12V_{DC}\$ to power some outdoor LEDs. The power supply as it stands will light the LEDs (with a slight flicker from the reverse ...
11
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4answers
19k views

Why do we use bridge rectifier?

If we already having a center tap rectifier with just two diodes doing the same work then why is there a need to use four diodes or the so called Bridge rectifier.
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5answers
11k views

Full wave rectifier vs full wave bridge rectifier

What is the difference between the full wave rectifier and the full wave bridge rectifier? In other words what do we gain if we use the bridge? As far as I know both do the same thing while the bridge ...
7
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1answer
2k views

What is the purpose of parallel RC network in the bridge rectifier output?

Can anybody explain the necessity of the RC network shown in the figure. I found this in circuit for a logic power supply using Fly-Back converter?
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2answers
16k views

Bridge rectifier in parallel?

Is it possible to safely double the current limit using 4 bridge rectifiers? In one forum I found someone wrote: Use four bridges, one for each leg. Tie the AC input (cathode to anode) ...
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3answers
4k views

Storing the charge from a MOSFET Bridge Rectifier

I am using the following MOSFET Bridge to harvest AC bursts, that come from an electromagnetic transducer. In front of this circuit is a supercapacitor I have added. I read the following on a ...
4
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2answers
9k views

Precise Full-wave rectification

I've been for quite some time now, trying to create a precise full-wave rectification of a signal coming from a CT sensor SCT-013-030. Here's the circuit: simulate this circuit – Schematic ...
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1answer
646 views

Measuring an AC-voltage at the ouput of a full bridge rectifier

I've a full bridge rectifier and I put the following function into it: $$5\sin(100\pi t)\tag1$$ So, at the output I get: $$\left|(5-2V_d)\sin(100\pi t)\right|\tag2$$ Where \$V_d\$ is the voltage ...
0
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2answers
49k views

Why are home appliances and other devices made to operate on dc? [closed]

Why are home appliances not designed to work on ac?why cant we just stepdown the incoming 230V and design the systems to operate at low ac voltages,instead of converting ac to dc?
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4answers
11k views

Why does this Bridge Rectifier claim to have no [Diode] Forward Voltage drop

I was, "OK, this is feasible"... But then I traced how it worked and it simply blocked current through Drain and Source when a P and N pair are reverse biased; then when the other P and N pair are ...
35
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3answers
22k views

What are the advantages of full wave bridge rectifier with capacitors parallel to diodes?

I found a circuit where in the classical Graetz rectifier capacitors were added in parallel to each diode. It looked something like this: After the rectifier itself, there was the usual huge ...
26
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3answers
66k views

AC to DC without transformer. How does this thing work?

I disassembled a Chinese-made flashlight and found they use just capacitors to bring down the voltage instead of a transformer. They are using it to charge small lead-acid battery. My question is how ...
5
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1answer
4k views

How does one compute the ripple currents seen by a rectifier filter capacitor?

Suppose one is designing a full-wave rectifier bridge, with a known maximum current load, and a known input inductance. Assume three-phase for this example, though the same concept applies to single-...
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5answers
2k views

Why don't more devices incorporate full-wave rectifiers as reverse polarity protection?

Recently, I was introduced to the idea of using a full-wave rectifier, in order to protect against reverse polarity damage in DC devices. I hadn't even considered using a rectifier in an already DC ...
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4answers
4k views

Determining amplitude of a 2 MHz sine wave

I'm designing a class E resonant inverter at a switching frequency of approx. 2 MHz. I need to control the inverter so as to maintain a constant current at the load. My strategy would be to put a ...
4
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2answers
37k views

230V to 12V step down transformer

I'm making a water level indicator using an 89C51 for which I need 5 V input voltage. I used a 230 V to 12 V step down transformer and a regulator to get 5 V. I got the 5 V but then the transformer ...
3
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3answers
17k views

Average output voltage of a fully controlled full wave rectifier

What is the average voltage for a fully controlled bridge rectifier with firing angle \$\alpha\$ ? In a lot of web resources it is said to be: $$\frac{V_{max}}{\pi} (1+ cos(\alpha))$$ For example ...
3
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3answers
5k views

Current transformer to ADC

I am planning to buy these current transformers which I am wanting to use to measure electricity consumption of a device where household power is 220V, 50Hz. I want to use these in combination with a ...
2
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1answer
888 views

precise half-wave rectifier problem

I'm actually trying to build a precise full wave rectifier. But after a first failed try, I though I would better be off break down things to analyse every part of the circuit. So, I started building ...
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2answers
14k views

Rectifier ripple voltage formula

So I thought the ripple voltage was approximated by the formula Vr,pp = Vp / fRC for a half-wave rectifier, and Vp/2fRC for a full-wave. Yet simulation shows ...
8
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3answers
9k views

Bridge rectifier: 4 diodes vs. single chip?

I notice (among the DIY audio enthusiasts at least) that when it comes time to design a power supply for an amplifier, DAC or whatever that the parts list will inevitably include something like "4 x ...
5
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3answers
1k views

Why AC supply is rectified first before stepping voltage down?

I have opened one of my phone chargers and was trying to understand how it works.. I found IC MB6F just at AC input which came out to be a bridge rectifier. My question is why AC is first rectified ...
3
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3answers
355 views

Oscillation in Voltage Rectifier / Scaling Circuit

I am working on creating a circuit that will scale +/- 12v input to a unipolar 3.3v centered around 1.65v, in order to scale the kind of CV used in modular synthesis systems to work with the ADCs on ...
3
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4answers
32k views

What happens if an AC voltage is applied to a battery?

Today I was checking the voltage between charging terminals going to the battery of emergency lantern using a multimeter. The multimeter showed a DC voltage of 9V and an AC voltage of 4V. Could ...
2
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2answers
2k views

How does this opamp full-wave rectifier work?

I want to understand how the following circuit works. I understand OpAmps, diodes, and voltage dividers pretty well; but put this circuit together, and I don't know how it affects positive or negative ...
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1answer
1k views

Interpreting the ripple curve of a half wave rectifier

While reading about how a half wave rectified output is filtered using a capacitor, I came across the following waveforms: corresponding to the circuit: In the interval from 0 to , the diode is ...
10
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4answers
5k views

No germanium diode available for small crystal radio — can active components handle the task?

I know that germanium diodes are trivial to find online, but as this is for a demonstration I'd rather not spend $6-7+ on shipping for a single 5 cent part for a project that's academic in exercise ...
8
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2answers
5k views

Center tap split supply question

Lest's say that I have the following setup: a split supply (using two voltage regulators: a positive and a negative one) connected to a center tapped transformer (12-0-12). The output of the ...
5
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2answers
2k views

Op amp rectifier : transfer function and output impedance

I'm working on an EE student project which uses a rectifier to keep the peak value of a sine wave. You can find a PSpice pic of the schematics below (Ve is the input (1kHz), Vs is the output). Op amp ...
4
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1answer
5k views

How to interpret diode-mode readings from a multimeter

I'm using this multimeter to examine a heat gun fan. The fan has four contacts placed in a circle (well in a square inside a circle). Two opposite each other are labeled ...
3
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4answers
3k views

Need help debugging my project: Fuses popping like crazy, but I can't find the reason why

I recently made a voltage and current controlled supply from a kit I found. It worked for about 15 minutes and then fuses started popping. Unfortunately, I have no idea why, because power supply ...
3
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4answers
6k views

How do I attach a bridge rectifier to a PCB or breadboard?

Newbie question here...I need to know the proper terminology so I know what I'm looking for. I have a bridge rectifier that has four flat blades on the bottom. I want to throw it on a breadboard to ...
3
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1answer
6k views

Connecting center-tapped transformer to earth ground; or, why am I being electrocuted?

Silly question here. I've wired up a full-wave rectifier using this dual-secondary transformer. If you want to check my wiring, I connected red-to-orange to "create" the center tap (I assume this is ...
2
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1answer
1k views

Common DC ground with two bridge rectifiers

I have an old AC transformer with many taps off it at different voltages. Connecting a voltmeter to tap 2 and tap 3 gives 25V and connecting it to 3 and 4 gives 5V. I connected them to two bridge ...
2
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2answers
389 views

Help me understand this load detecting circuit

I'm looking at this circuit: Which has come from here The claim is made that "it detects a voltage drop across a large bridge rectifier that acts as a high power shunt", which is referring to the ...
2
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2answers
964 views

What are the ratings of vintage Selenium Rectifier B20/16-2,4?

Sort-of a follow-up to How to ground a vintage device that was powered without a ground? in that the device is the same. I finally took the leap and opened up the old charger (depicted in the linked ...
2
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2answers
1k views

Problems with efficiency and heat in a rectifier

I have too much heat in a rectifier so there is a considerable efficiency loss. I've been searching about it and I've found it could be because forward voltage or even because high frequency AC input. ...
2
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3answers
2k views

AC heater, bridge and MOSFET, possible?

In my project I already have all the circuits for a PWM driving some high power MOSFET. Now the hardware guys are coming with this AC heater, and I've been breaking my head around Triacs and phase ...
2
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1answer
4k views

Does a bridge rectifier care that much for AC frequency?

As I understand it, a bridge rectifier is a set of diodes that play a trick of logic that keeps the polarity positive. So, within the context of a household DC transformer does it matter what the ...