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You can find many very circuit ideas at ePanorama.net circuits page.
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Tomi Engdahl says:
This practical guide to #signalintegrity in high-speed #SerDes applications covers real-world issues that require additional analysis, modeling & compensation ON Semiconductor #PCB #redrivers https://buff.ly/3e3eCca
Tomi Engdahl says:
https://groupdiy.com/index.php?topic=64510.0
The problem with Toroids is that NEVER HALF WAVE RECTIFY the outputs of them. If you half wave rectify it will cause a DC BIAS to the core and this can saturate the core and the transformer will draw lots of current/blow fuses/open the internal current limiter.
Some measurements of the effect you can see on Elliot’s site here
http://sound.whsites.net/xfmr2.htm#s1
This is a great overview on transformers. This tests are on a EI core transformer. The EI core has an AIR GAP while a TOROID has no AIR GAP and the core bias in way higher.
Tomi Engdahl says:
Circuit performs high-speed voltage-to-current, current-to-current conversion
https://www.edn.com/circuit-performs-high-speed-voltage-to-current-current-to-current-conversion/?utm_source=newsletter&utm_campaign=link&utm_medium=EDNDesignIdeas-20200519
The circuit in Figure 1 performs active voltage-to-current conversion or acts as a variable-gain current mirror with high precision and bandwidth. A typical application is testing high-speed ICs or other devices that have inputs designed to be driven from current-steering DACs to enable a modulated voltage source to control the devices. The circuit thus simplifies the testing of such devices in isolation, because modulated voltage sources are readily available, but modulated current sources generally are not.
Tomi Engdahl says:
Create radio receiver circuits with the LM386 audio amplifier
https://www.edn.com/create-radio-receiver-circuits-with-the-lm386-audio-amplifier/?utm_source=newsletter&utm_campaign=link&utm_medium=EDNDesignIdeas-20200519
May 15, 2020
by Martyn McKinney
Comments 0
Although the ubiquitous LM386 IC was designed to be used as an audio amplifier, it has a number of undocumented characteristics that can be exploited to create simple radio receiver circuits that deliver surprisingly high performance. These circuits can be used for receiving AM, CW, and SSB RF transmissions in the medium and shortwave bands without the need for an external antenna.
Tomi Engdahl says:
Safe to run uneven loads on toroid secondaries?
https://groupdiy.com/index.php?topic=64510.0
The problem with Toroids is that NEVER HALF WAVE RECTIFY the outputs of them. If you half wave rectify it will cause a DC BIAS to the core and this can saturate the core and the transformer will draw lots of current/blow fuses/open the internal current limiter.
Some measurements of the effect you can see on Elliot’s site here
http://sound.whsites.net/xfmr2.htm#s18
This is a great overview on transformers. This tests are on a EI core transformer. The EI core has an AIR GAP while a TOROID has no AIR GAP and the core bias in way higher.
I was not particularly impressed or convinced. Most EI core mains transformers have no gap and there is no mention of a gap being present in the tests conducted in the article referred to. All that is demonstrated is that half wave rectification is inefficient (which we knew anyway) and that it causes an asymmetric primary waveform. An asymmetric waveform is not of itself a problem. We get asymmetric audio waveforms all the time. Provided the transformer does not saturate there is no problem. The dc offset in the half wave rectifier does mean one polarity will saturate before the other but that is all. Problems will occur if you try to draw the same power from a half wave rectifier as you could get from the equivalent full wave recitifier but that would just be poor design.
All EI transformers have a gap.
The spec sheets for Traids state explicitly that the secondaries are not to be used independently, the spec sheet for the hammonds eludes at the same saying they are intended to be connected in series or in parallel…
The only company I have found that gives you the green light for independent and uneven secodaries is Avel Lindbergh.
http://www.avellindberg.com/transformers/y23_range_connections.htm
Also turns out they make fantastic transformers and with small minimums are a great resource for custom wound transformers.
EI transformers can be built in two ways. I ungapped ones the EI laminations are linterleaved alternately. This means that although there are very small gaps between E and I on each layer (which causes flux leakage), there is no overall gap in the main flux path. To make a gapped EI transformer you stack the laminations rather than interleaving them and place a thin piece of paper for example between the E stack and I stack to make the gap.
For more info check out Bill Whitlock’s excellent treatise on audio transformers from the Hanbook for Sound Engineers in the Iron folder of the DIY tab of my web site:
http://www.customtubeconsoles.com/diy
As I said all EI transformers have a gap, with interleaved lams or not, and higher overall magnetic reluctance than toroids.
There are also some variants in EI lams stacking. You will find some PP output transformer designs where 4 or so lams are staked in one direction and then interleaved, just to tolerate a small disbalance (DC) in PP tubes anodes current.
Not all EI transformers have a gap in the main flux path and that is what counts.
You are wrong here. You can’t align E and I lame in order to avoid a small gap. Because of that C core are used where the contact surface between two cores are tightly machined and polished. And two cores are always paired. This type of transformers has much smaller magnetic reluctance.
Then perhaps you can explain to me how Carnhill havegapped and ungapped versions of many of their output transformers, all of which are made with EI laminations.?
“Gapped” or “ungapped” is a simplified classification of (audio) transformers. If one transformer is signed as ungapped you shouldn’t bias it with DC. But, some ungapped transformers will tolerate a small DC bias (when for example discrete opamps API2520 drive line output 2503 transformers in API preamps), some other transformers will not.
What I like to say here but you don’t like to hear is that “ungapped” EI (power) transformer has not the same BH characteristic as an equivalent toroidal transformer. One reason for that is impossibility to stack ideally E and I laminations in an EI transformer. Toroidal transformers have much steeper BH characteristic and have much higher sensitivity to DC in primary or to uneven load.
I have carried out some research and I have to admit you are basically right. All EI transformers have some form of gap or gaps – it is inevitable in their construction – but so called ungapped ones take special care to ensure they are as small as possible so that their inductance is mazimised
Tomi Engdahl says:
https://www.electronics-tutorials.ws/transformer/audio-transformer.html
Tomi Engdahl says:
The High-End Mythology of the Toroidal Power Transformer
http://www.soundstagenetwork.com/maxdb/maxdb071998.htm
Tomi Engdahl says:
Full Wave Rectifier
https://www.electronics-tutorials.ws/diode/diode_6.html
Tomi Engdahl says:
https://electronics.stackexchange.com/questions/216959/what-does-the-y-capacitor-in-a-smps-do
Tomi Engdahl says:
https://tools.analog.com/en/filterwizard/
Tomi Engdahl says:
d.i.y. 250 kV High Voltage DC Power Supply with Neat Trick for Switching Polarity
http://www.diyphysics.com/2012/02/09/d-i-y-250-kv-high-voltage-dc-power-supply-with-neat-trick-for-switching-polarity/
Tomi Engdahl says:
https://www.baldengineer.com/7-mosfet-myths-and-misconceptions-addressed.html
Tomi Engdahl says:
added a resistor to the MOSFET’s gate pin. Of course any time a resistor is shown in a schematic, people get worried about what complicated formula is needed to determine its value. For slow switching applications, like below 10 kHz, the resistor value doesn’t matter. Something in the 100 to 1000 KOhm range is fine.
So if the value does not matter, why have one? The gate of a MOSFET is a small capacitor.
The initial current is very high. It slows down as the capacitor charges. That initial current rush, also known as in-rush current, can be a problem. Even though it is a short time, there is a significant current surge that can damage an I/O pin.
https://www.baldengineer.com/7-mosfet-myths-and-misconceptions-addressed.html
Tomi Engdahl says:
ESD Classifications
https://www.rs-online.com/designspark/esd-classifications
Human-Body Model and Electrostatic Discharge (ESD) Tests
https://incompliancemag.com/article/human-body-model-and-electrostatic-discharge-esd-tests/
Tomi Engdahl says:
https://electronics.stackexchange.com/questions/28251/rules-and-guidelines-for-drawing-good-schematics
Tomi Engdahl says:
https://www.electronicdesign.com/technologies/analog/article/21131760/input-protection-for-lowdistortion-opamp-circuits?utm_source=EG+ED+Analog+%26+Power+Source&utm_medium=email&utm_campaign=CPS200519051&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R
Tomi Engdahl says:
https://www.electronicdesign.com/technologies/analog/article/21131133/critical-design-issues-for-a-functioning-jesd204b-interface?utm_source=EG+ED+Analog+%26+Power+Source&utm_medium=email&utm_campaign=CPS200519051&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R
Tomi Engdahl says:
https://sparepartkings.co.ke/beginners-guide-to-electronics-identification-of-pcb-symbols/
Tomi Engdahl says:
https://electrocircuits.org/transistor-acting-as-an-amplifier/
Tomi Engdahl says:
Simple Power Inverter Circuits 100W to 1000W
https://electrocircuits.org/simple-power-inverter-circuits-100w-to-1000w/
This post is for those searching for power inverter circuits. It contain Simple Power Inverter Circuits with 100W to 1000W or more outputs. Even a learner can construct this circuits!
Tomi Engdahl says:
Smoothing and Filter Capacitor Calculator
https://electronicbase.net/smoothing-capacitor-calculator/
Capacitor Smoothing Circuits & Calculations
https://www.electronics-notes.com/articles/analogue_circuits/power-supply-electronics/capacitor-smoothing-circuits.php
Reservoir capacitors are used to smooth the raw rectified waveform in a power supply – it is important to chose the right capacitor with the correct value and ripple current rating.
Tomi Engdahl says:
LINEAR POWER SUPPLY DESIGN ASSISTANT #1
This first part deals with rectification / smoothing capacitors.
https://www.changpuak.ch/electronics/power_supply_design.php
Tomi Engdahl says:
https://electronic-circuits-4u.blogspot.com/
Tomi Engdahl says:
http://www.circuitstoday.com/simplest-lamp-flasher-circuit
Tomi Engdahl says:
LED Flasher Circuit
https://www.youtube.com/watch?v=UuyKQg2aWQU
Tomi Engdahl says:
https://components101.com/7805-voltage-regulator-ic-pinout-datasheet
https://www.quora.com/Can-a-7805-regulator-actually-be-used-as-a-switching-converter
Tomi Engdahl says:
https://www.electroinvention.co.in/active-and-passive-components
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/05/piezoelectric-sensor.html
Tomi Engdahl says:
https://www.allaboutcircuits.com/textbook/reference/chpt-2/wiring-color-codes/
Tomi Engdahl says:
#49: Simple Component Tester using Oscilloscope – Octopus Curve Tracer
https://www.youtube.com/watch?v=Gwo3pEH7hUE
Tomi Engdahl says:
Samsung patches 0-click vulnerability impacting all smartphones sold since 2014
Samsung patched this month a critical bug discovered by Google security researchers
https://www.zdnet.com/article/samsung-patches-0-click-vulnerability-impacting-all-smartphones-sold-since-2014/
Tomi Engdahl says:
https://circuits-diy.com/heartbeat-sensor-circuit-using-lm358-electronics-projects/
Tomi Engdahl says:
Op Amp Circuits: Analog Computers from operational amplifiers
https://www.youtube.com/watch?v=_o4ScgRZtNI
Tomi Engdahl says:
https://en.wikipedia.org/wiki/Selenium_rectifier
Tomi Engdahl says:
https://www.edn.com/the-basics-of-testing-op-amps-part-1-circuits-test-key-op-amp-parameters/
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/05/7-seven-segment-display.html
Tomi Engdahl says:
https://www.edn.com/a-practical-guide-to-signal-integrity-in-high-speed-serdes-applications-part-1/
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/05/three-phase-induction-motor.html
Tomi Engdahl says:
https://en.wikipedia.org/wiki/Nine-volt_battery
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/05/difference-between-serial-and-parallel-communication.html
Tomi Engdahl says:
HOW TO MAKE ADJUSTABLE POWER SUPPLY|VOLTAGE REGULATOR USING MOSFET
https://www.youtube.com/watch?v=QDGWbrmp124
https://www.google.com/search?q=irfz44+voltage+regulator&oq=irgz44a+regulator&aqs=chrome.1.69i57j0l3.8553j0j7&client=ms-android-samsung-ga-rev1&sourceid=chrome-mobile&ie=UTF-8#imgrc=1XlcF6E41xb-QM:
Tomi Engdahl says:
How to make Mini solar charger controller circuit using Two Transistor
https://www.youtube.com/watch?v=8EDLUluE9b8
Tomi Engdahl says:
John Errington’s tutorial on Power Supply Design
Smoothing
http://www.skillbank.co.uk/psu/smoothing.ht
LINEAR POWER SUPPLY DESIGN ASSISTANT #1
This first part deals with rectification / smoothing capacitors.
https://www.changpuak.ch/electronics/power_supply_design.php
Tomi Engdahl says:
https://www.electrosmash.com/jrc4558-analysis
The JRC4558 integrated circuit by Japan Radio Company is a dual operational amplifier internally compensated and constructed with bipolar transistors on a single silicon chip. The high voltage gain (100 dB typ.), good input impedance (5 MΩ typ.) and versatile power supply (± 4 to 18 Volts) make it perfect to fit in pedal circuit designs. This chip has industry standard pinout, meaning that there are several different suppliers manufacturing pin compatible 4558 devices and also it can replace other standard dual op-amps like the TL072, NE5532 or the OPA2134. The first RC4558 monolithic dual opamp was developed by Raytheon Semiconductors in 1974.
The 4558 dual amp is linked with the history of the guitar pedals development. Many designers included this part in some of the most successful effects like the Orange Squeezer, DOD YJM 30, Boss OD1, Tube Screamer or Peavey equipment.
Tomi Engdahl says:
Obstacle Avoiding ROBOT without MICROCONTROLLER
https://www.youtube.com/watch?v=kICj8q2JlF8
Tomi Engdahl says:
Common Coaxial Cable Specifications
http://www.repeater-builder.com/antenna/wa2ise-coaxial-cable.html
Tomi Engdahl says:
http://www.resistorguide.com/resistor-color-code/
Tomi Engdahl says:
Speed Control of DC Motor – Voltage, Rheostatic & Flux Control Methods
https://www.electricaltechnology.org/2020/05/speed-control-dc-motor.html
Tomi Engdahl says:
This Flyback Converter Design Really Steps Up to the Plate
https://www.hackster.io/news/this-flyback-converter-design-really-steps-up-to-the-plate-77449f90a6d9
James Wilson’s textbook flyback DC/DC converter implementation is a wonderful lesson in converter design!
Tomi Engdahl says:
https://www.stdiscovery.gq/2018/11/network-circuit.html