Questions tagged [ripple-current]

Small unwanted residual periodic variation of the direct current (dc) output

Filter by
Sorted by
Tagged with
0
votes
2answers
50 views

Inductor current ripple ratio of buck boost converters

I have a question about this paper: https://ieeexplore.ieee.org/document/1210630 I have always thought that the maximum current ripple of a buck converter occurs with a duty cycle of 0.5. The paper ...
3
votes
3answers
103 views

Boost LED driver output spikes

I designed a boost LED driver based on TPS92691. It drives 56V 5A COB LED from 22-50V input. It works ok. Oscilloscope shows small spikes on input (100mV), but large spikes on output (3V). The spikes ...
0
votes
0answers
14 views

Inverter feed induction motor FOC Control - Stator current ripple

let us assume I am using an AC motor. It is in field oriented control. I want to see the motor rotating at 2.99Hz. Since slip speed is equal to 0.03Hz and the pole pairs number is equal to 2 I assume ...
3
votes
1answer
280 views

What might this term (N sub C) be, calculating ripple current for a buck converter output capacitor?

I'm reading through the datasheet for TI's TPS54302 step-down converter, and determining values for support components. There is a calculation to determine ripple current for the output capacitor ...
2
votes
2answers
167 views

Understanding inductor and LED ripple current in LM3409

I am reading the datasheet of the LM3409, specifically section 9 "Application and implementation". My intent is to understand how to calculate the values of the components needed for my specific ...
0
votes
2answers
482 views

What causes SMPS voltage ripple?

In many datasheets and application guides there is always an equation for ripple current, because it is fundamental to the operation of a buck or boost converter, but I never see a direct equation for ...
1
vote
0answers
76 views

How to convert Ripple Current spec to ESR?

It used to be that vendors like Digikey gave a cap's ESR value and not ripple current. Nowadays, it seems more report only ripple current and not ESR. What gives with that? So what are we supposed to ...
0
votes
1answer
295 views

How to measure 120 Hz ripple current at the output of an LED driver?

I have a 50W LED driver and a programmable load. Please suggest a way to measure 120Hz ripple current! I have an oscilloscope and multi-meters.
1
vote
0answers
116 views

What will be the output ripple current per capacitor buck regulator?

I have a existing buck regulator design. Converter part number: TPS54340Q1. Input voltage = 5 V. Output voltage = 3.3 V RMS ripple current is calculated as = 108 mA. (Don't worry too much about ...
1
vote
2answers
787 views

Ripple Current in Boost Converter for Nixies

I'm trying to design a power supply for 6 IN-8 Nixie Tubes (driven individually, not multiplexed). Each tube has a current draw of 2.5-4.5mA, so they pull around 30mA(max) total. The input voltages is ...
-1
votes
1answer
247 views

Buck-Boost power supply I_ripple calculation

I'm not looking to get torn apart, just looking for a hand. I can't remember exactly how to calculate the RMS Current required from the output capacitors or a Buck-Boost power supply and I was hoping ...
0
votes
1answer
1k views

How do you identify what capacitor to use to filter DC voltage ripples from a bridge rectifier? (capacitance, etc.)

Let's say I have reduced 220V 60Hz AC to 1.5V 750mA AC with a step-down transformer and used a bridge rectifier consisting of 4 IN4007 diodes to convert it to DC. How do I math this down?
1
vote
2answers
256 views

Is this inductor and caps a good choice for a buck converter?

I wanted to get together a simple and efficient 12V to 5V switching power regulator using only through-hole components that can be soldered to a nice protoboard. For my purposes, I need to provide 0....
1
vote
2answers
5k views

capacitor voltage ripple in buck converter

I am struggling with output voltage ripple calculation of the buck converter below. Firstly, I don't understand the following statement from the lecture. Can anyone explain it? If the capacitor ...
4
votes
4answers
3k views

Ground plane directly underneath physically large 100 µH inductor?

I plan to use a physically large ferrite core inductor (Murata part "1410478C", 100 µH at 1 kHz) in a 12 V, 7 A DC filter circuit. It will be mounted on topside of a four-layer PCB ...
0
votes
1answer
677 views

Determining the input capacitance for a SMPS [closed]

I'm attempting to layout a SMPS using the LTC3703 chip, however the datasheet doesn't talk about the AMOUNT of input capacitance, just that it be low esr. However, it does talk about "bulk ...
0
votes
3answers
153 views

Ripple flowing through probes connected to the same point!

While trying to filter the ripple of my switching PSU, I've come to a phenomenon that is probably well known to professionals, but seems absurd to me. Admittedly, my scope is not of the highest ...
0
votes
1answer
318 views

How to protect constant LED current from ripples & clamps?

I need to develope a constant current LED Driver. The product must be portable and as small as possible. So I can not use SMPS, I have use AC/DC adapter as source. This is the AC/DC adapters output: ...
1
vote
2answers
534 views

Ultra low ripple constant-current LED driver design

I designed a LED driver(SMPS configuration) with ILD6150XUMA1 and below is the circuit. I used it with AC/DC adapter. The thing is, th optical system is ultra sensitive and ripple from the LED ...
1
vote
4answers
657 views

Measure indcutor ripple current in a SMPS

I need to measure the ripple current in a buck converter. In general, I add leads to the inductor and use a current probe. My issue now is that the inductor I am using has such a low inductance that ...
1
vote
0answers
269 views

How to estimate ripple current for PWM loads?

I'm buying some caps for a PCB which I'm designing, and I'm not quite sure how to estimate the ripple current they need to be. This PCB is intended to switch about ~15A from 12V to 24V at ~100kHz. ...
0
votes
5answers
517 views

What is the problem with charging a (lead-acid) car battery with AC power?

The closest thread I've found (which didn't show up in the automated suggestions) was What happens if an AC voltage is applied to a battery?. Unfortunately, I felt like the answers were more aimed at ...
2
votes
1answer
151 views

Where can I find a stable AC to DC switching power supply?

I've purchased multiple 3V switching power regulators form Amazon and they all have spikes in the ripple. Here's an O-scope capture: The spikes increase frequency depending on the load. Are these ...
5
votes
1answer
2k views

Capacitor Ripple Current - Frequency coefficient

I am designing a motor controller with a 11A max start load and 3A max continuous load. Looking for capacitors I found in this datasheet a "Frequency coefficient for ripple current", what is that and ...