First, some background. I have designed an SCR trigger board using an IRS24541 self-oscillating FWB driver and two dual MOSFETs FDS6930B...

First, some background. I have designed an SCR trigger board using an IRS24541 self-oscillating FWB driver and two dual MOSFETs FDS6930B (30V, 5A, 0.055 RdsOn, 2W). I made a couple of transformers using EPCOS E187 or E16-8-5 cores with N27 ferrite having an Al of 950 nH. I used about 20 turns of #32 AWG wire on both primary and secondary, to get 12 VDC out with 12 VDC input. Running at ...

I'm interested in making a load cell scale using an Arduino so I can program special features that currently available scales don't...

I'm interested in making a load cell scale using an Arduino so I can program special features that currently available scales don't have. Any thoughts on best way to get high resolution data to an Arduino microcontroller board? AD7730 chip, or Instrumentation amp to A/D converter? Anything readily available such as load cell in and serial data out? Most of the ready made load c...

Hi So I wanted to check the VCE of a transistor in a small converter running at 100kHz, expected to see about 100mV above ground as...

Hi So I wanted to check the VCE of a transistor in a small converter running at 100kHz, expected to see about 100mV above ground as the saturation voltage of the NPN, increasing linearely since magnetising current increasing. I saw nothing like that, debugging and found the scope (Tek DPO5000) somehow saturates with high voltage inputs. The signal is a square wave of 100kHz, 25V peak to...

Hi all. I need a basic voltage mode PWM controller for a buck converter project. I need a wide duty cycle range, like 5 - 95%. I don't need an...

Hi all. I need a basic voltage mode PWM controller for a buck converter project. I need a wide duty cycle range, like 5 - 95%. I don't need an error-amp in the ic, since this part is placed elsewhere in my circuit. So, a basic Ramp generator and a PWM comparator, and an output stage. An UC3843 would suit if it were voltage controlled instead of current. I've gone through Fairchild, ONsemi we...

Hi, The input DC voltage is in the range of 1.2 volts to 40 volts. I need 3.3 volts output and 300mA. So. I decided to use LT3759. LT3759's...

Hi, The input DC voltage is in the range of 1.2 volts to 40 volts. I need 3.3 volts output and 300mA. So. I decided to use LT3759. LT3759's data sheet is at the following link http://cds.linear.com/docs/Datasheet/3759fa.pdf Plan is to configure the LT2759 to generate 5 volts @ 300mA and then use LT 1962 to generate 3.3 Volts at 300mA. 300mA is maximum but load will work between 150mA to...

Dear All, I am now making a 48 V to 120V Boost Converter (with a single series 560uH 10A inductor) using PWM IC SG3524, and I am a little...

Dear All, I am now making a 48 V to 120V Boost Converter (with a single series 560uH 10A inductor) using PWM IC SG3524, and I am a little bit confused with the use of error amplifier input pins (pin 1 and pin 2) and the compensation pin (pin 9). A typical example application circuit (see figure 13) divides the reference voltage 5V to 2.5V, and feeds it to pin 2 as reference. The output is ...

This is an about -30 dBu sine wave being amplified to about 0dBu by the triode section of a Sylvania 12EC8 triode/pentode "space charge" tube....

This is an about -30 dBu sine wave being amplified to about 0dBu by the triode section of a Sylvania 12EC8 triode/pentode "space charge" tube. The plate load is a single transistor gyrator/constant current source. Plate and heater currents are being supplied by a "China Special" boost converter module that's stepping up a 4 "C" cell battery pack. http://tinyurl.com/zeegduc Yick. Lots...

Just a good idea, my humble opinion: ASIC is expensive, and the chip companies earn good profits on selling commodity chips Commodity chips:...

Just a good idea, my humble opinion: ASIC is expensive, and the chip companies earn good profits on selling commodity chips Commodity chips: opamps, regulators, diodes, transceivers etc If we go together and do some designs, splitting the NRE, we could buy chips at only production cost, maybe half price of normal purchase price So the typical high voltage buck converter, the LDO, the ...

x-Chapters 9x.16, about DC transformers, AKA bus converters. It's a synchronous dc-dc converter, with in/out voltage ratio set by a fixed...

x-Chapters 9x.16, about DC transformers, AKA bus converters. It's a synchronous dc-dc converter, with in/out voltage ratio set by a fixed switching duty cycle. Like ac transformers, they transfer power in either direction, as a function of who's above the ratio. The current-ratio also obeys the voltage-ratio rule, like an ac transformer. As bus-converters, they're used to conver...

Since there haven't been enough serious design articles in a while, I thought I'd write one. Some time ago I had questions about the problems...

Since there haven't been enough serious design articles in a while, I thought I'd write one. Some time ago I had questions about the problems I encountered building a switching power supply to drive a 60mA current loop Teletype from a USB port. I wanted to power it entirely from the USB port, and finally succeeded. Here's the schematic: https://image.ibb.co/mW08yF/board2_3.png The f...

I have seen a design for a high-power (200kW) AC motor controller that uses dual-inductor AC line chokes for a DC-DC converter for IGBT gate...

I have seen a design for a high-power (200kW) AC motor controller that uses dual-inductor AC line chokes for a DC-DC converter for IGBT gate drive power supplies. http://enginuitysystems.com/pix/electronics/200kW_AC_Controller_p3.png I have found some chokes rated 500 uH and 1 amp, with 250 VAC rated isolation, for less than a dollar each: http://www.mouser.com/ds/2/212/KEM_LF0016_SU9V-...

I'm going to have one board in the front of a rackmount box, the controller, with an FPGA. In the back of the box will be an output board with...

I'm going to have one board in the front of a rackmount box, the controller, with an FPGA. In the back of the box will be an output board with an ADUM7703 isolated delta-sigma converter measuring current. The boards will be connected by an 18" ribbon cable. The signals are a 20 MHz clock to the ADUM and 20 mpbs delta-sigma data coming back to the FPGA. Both sigs are source terminated. I...

Hello, I am trying to simulate a buck and a boost converter using Christophe Basso's generic PWM models (in LTSpice) for voltage mode...

Hello, I am trying to simulate a buck and a boost converter using Christophe Basso's generic PWM models (in LTSpice) for voltage mode controlled and current mode controlled switched mode power supplies. These models have an integrated PWM generator and power switch. These models can be found here: http://cbasso.pagesperso-orange.fr/Downloads/IsSpice/Final%20models.zip (alternati...

This is the relevant part of the schematic of an 18650 battery charger and boost converter (to 5V)...

This is the relevant part of the schematic of an 18650 battery charger and boost converter (to 5V) module: https://i.postimg.cc/Tw7X35Fq/USB-to-TP4056.jpg And here's the module: https://www.aliexpress.com/item/32870411748.html Coming from the USB power pin, there's a series Schottky diode and a very low value resistor. The resistor is found in the TP4056 datasheet typical applic...

Hi I am working on a high power frequency inverter (> 1kW) and have a "funny" looking emission graph The converter is the typical inverter...

Hi I am working on a high power frequency inverter (> 1kW) and have a "funny" looking emission graph The converter is the typical inverter type, EMC filter-> 3 Phase Rectifier-> DC Inductor-> DC Link capacitor-> 6 switch Inverter-> Motor Like this: www.electronicsdesign.dk/tmp/Inverter.jpeg We stripped down the circuits and isolated the noise to the EMC filter and bridge rectifier. T

I have found a number of free utilities that may be of assistance to others. Can't read DOC or DOCX files? See Convert DOC to...

I have found a number of free utilities that may be of assistance to others. Can't read DOC or DOCX files? See Convert DOC to HTML https://document.online-convert.com/convert-to-html Want to annotate PDF information? See Free PDF to HTML Comversion https://www.pdftohtml.net/ Want to convert HTML to PDF? See HTML to PDF Converter https://html2pdf.com/ PDF file won't let you copy i...

Hi, Based n Sepic DC/DC converter from Larkin, i investigate to make a Cuk from it and it works finally. Version 4 SHEET 1 2996...

Hi, Based n Sepic DC/DC converter from Larkin, i investigate to make a Cuk from it and it works finally. Version 4 SHEET 1 2996 1968 WIRE 0 880 -80 880 WIRE 160 880 80 880 WIRE 688 880 160 880 WIRE 944 880 832 880 WIRE 1024 880 944 880 WIRE 1664 880 1088 880 WIRE 1792 880 1664 880 WIRE 1936 880 1792 880 WIRE 2048 880 1936 880 WIRE 2160 880 2048 880 WIRE 832 896 832 880 WIRE 16...