All Questions
60
questions
0
votes
2
answers
1k
views
High Voltage PWM
I really hope someone can help me with this difficult issue:
I want to generate a PWM signal from a 170V DC input.
ok, so far I have an arduino that can generate a PWM signal and drive a MOSFET that ...
- 11
0
votes
1
answer
387
views
PWM average voltage smoothing
I built an ESC circuit. First, I tested it with a drive frequency of 350 Hz; the speed was at about 20 RPS at a 70% duty cycle.
But when I changed the drive frequency to 20 kHz, I noticed that the ...
- 121
1
vote
0
answers
125
views
Inductor saturation current
I'm trying to determine an inductor's saturation current, I use a PWM with a gate driver (TLP250) and a 0.4Ω sense resistor at the source which I probe across to capture the current waveform.
I ...
- 41
-1
votes
1
answer
108
views
Battery Type Buck Converter With Bootstrap MOSFET Driver
I have a device that used 2x 1.2 V NiMH batteries that I want to change to use a Li-Ion cell. I want to map the 3.3 - 4.2 V voltage range of the Li-Ion to the 2.0 - 2.4 V of the NiMH using PWM.
I use ...
- 139
0
votes
1
answer
365
views
Step-down converter in an ATX PSU, why?
I was recently looking at a 500W PSU schematic, and found out they used step-down converters on 12v and 5v output. Schematic is attached(pls see hi-res at https://ibb.co/nbDRJPq)
The D2 diode charges ...
- 392
-1
votes
2
answers
323
views
Synchronous DC-DC buck converter I saw online
I constructed this synchronous buck converter circuit I found online and I wanted to know how reliable it actually is: ( I used a battery source for the VCC+ pin on the op-amp because the 12 V line ...
- 633
0
votes
1
answer
284
views
DC -DC buck converter W/o PWM signal( kind of)
Hey so i'm new to electronics and I've tried constructing a buck converter (using software only) circuit without the use of an external PWM source (microcontroller, 555 circuit) and i came up with ...
- 633
0
votes
1
answer
183
views
EMI input filter for low frequency heater controller [duplicate]
A meanwell 24V, 280W AC-DC power adapter is used to supply a PWM-driven heater control circuit.
The power adapter is fully enclosed and protected (model GST280A24).
The load is a pure resistive ...
- 1,025
1
vote
0
answers
101
views
How to select external components for a buck converter?
I design a simple circuit activates fan when processor heats up and then control rotation speed. The fan has a brushless motor with an internal motor controller. So I got the idea to create a buck-...
- 21
1
vote
2
answers
324
views
Idiomatic way to control output voltage of buck/boost converters using microcontroller
I'm trying to design an appliance that efficiently regulates power to some Peltier elements.
The manufacturer states that optimally, you should drive these with regulated voltage and not PWM. They ...
- 171
0
votes
1
answer
209
views
What is the relation between the control voltage and resulting pwm in a voltage-mode control system for DC-DC converters?
I'm currently learning about negative feedback and voltage mode control for various DC-DC converters. I'm very confused about how the control voltage changes the pwm signal, along with how the ...
- 1
4
votes
1
answer
901
views
DC/DC Switching Converters: Is it possible to run a current-mode converter in voltage-mode only?
DC/DC Switching Converters: Is it possible to run a current-mode converter in voltage-mode only?
If so, is there an example using a buck converter?
In particular, I'd like to use UC3843 (LT1243) in ...
- 45
0
votes
1
answer
77
views
Voltage Mode Buck Converter Output Voltage
I am trying to design a simple buck converter. But it doesn't work as expected. Output voltage should be 19V but it is very close to input with value 48.5V. Also there is a problem with pwm generator.
...
- 1
1
vote
1
answer
1k
views
PWM modulator in voltage mode buck converter
I am referring to datasheet of LM3743 block diagram in page 5.
The EA and PWM Comp is in leading edge modulator configuration. According to my understanding SR latch which comes after PWM Comp must ...
- 305
0
votes
1
answer
3k
views
Why Gate voltage must be higher than source voltage in N-MOSFET as High side switch?
In many circuit, like buck converters, MOSFET used in high side for switching, I've came across the term that Gate voltage with respect to ground must be greater than source voltage by +8V.
For ...
- 97