Steve Arar

1 month ago | allaboutcircuits.com | Steve Arar |Jake Hertz

Technical Article This article highlights a selection of circuits used for amplitude modulation, including a switching modulator built with just one diode and a circuit that incorporates a Class C power amplifier. There are numerous ways to implement amplitude modulation (AM). So far, this article series has discussed four of them: The square-law modulator. The balanced modulator. The diode bridge modulator. The ring modulator. In this article, we’ll explore four more.

1 month ago | forum.allaboutcircuits.com | Steve Arar |Jake Hertz

Dear AllI found an AB audio amplifier schematic online, and ordered the PCB. The issue is that the mosfets connected to the upper VCC are working, but seem to become extremely hot. The other mosfets connected ot the lower VCC are seem not to be working. A lot of testing has been done, but no improvements. When I simulate this in software (falstad) like multisim. I see that the two mosfets connected tot the - VCC are not switching. A picture of the schematic and simulation below. Someone any idea?

2 months ago | allaboutcircuits.com | Steve Arar |Mike Falter

Class F amplification is a well-established technique that uses harmonic tuning to improve the amplifier’s performance. In a Class F amplifier, odd harmonics are added to the collector voltage to shape it into a square wave. The collector current, which is ideally a half-sine wave, contains the fundamental and even harmonics. An inverse Class F amplifier, also known as a Class F-1 amplifier, swaps the shape of these waveforms.

2 months ago | forum.allaboutcircuits.com | Steve Arar |Jake Hertz

Hi, Currently I'm considering to design a Dynamic Brake Unit (DBU) for V.F.D. DBU power range is around 15KW and VFD is 400V class. Recommended resistor value is 40 Ohm 2kW. I know the basic of DBU and will manage the voltage selection and PWM things via Micro-Controller. My major concern in this post is related to a safety issue relative to IGBT.

2 months ago | forum.allaboutcircuits.com | Luke James |Steve Arar

Hello,Thank you fore reading my question. I'm using EasyEDA Standard and trying to add smd parts (LCSC) for assembly. When I create the BOM everything looks good, but then when clicking "order parts" mostly wrong parts are added. Step 1, I click the "B" icon in the upper right corner of the menu items of EasyEDA and see the BOM with correct partsStep 2, I click on the "order parts" button and then see my BOM with many wrong parts.