https://www.eevblog.com/forum/metrology/film-and-ceramic-capacitor-leakage-current/ Tim -- Seven Transistor Labs, LLC Electrical...

https://www.eevblog.com/forum/metrology/film-and-ceramic-capacitor-leakage-current/ Tim -- Seven Transistor Labs, LLC Electrical Engineering Consultation and Design Website: https://www.seventransistorlabs.com/

Anyone familiar with a high voltage charge pump designed as a step down power supply? The voltage is between 175 & 200. Numerous high...

Anyone familiar with a high voltage charge pump designed as a step down power supply? The voltage is between 175 & 200. Numerous high voltage versions exist using inductors, (Onsemi has one that is "self supplied" which is attractive) but not a one that works with just a capacitor. Are there any out there I've missed? Hul

Could someone here shed some light on this ? I am experimenting with envelope detection at RF frequencies with SPICE. The mixer is a simple...

Could someone here shed some light on this ? I am experimenting with envelope detection at RF frequencies with SPICE. The mixer is a simple SPICE B signal source as B0 3 4 V(1)*V(2) where 1, 2 are the nodes at which the two signal sources are attached. THe mixer output is fed into a Schottky diode(1N5818, BAR42 etc.,) and a shunt capacitor is attached to the Schottky diode cathode. ...

Is there any reason not to use a 20-uF 900-volt film capacitor as a power supply filter? I'm updating a vintage Heathkit capacitor checker that...

Is there any reason not to use a 20-uF 900-volt film capacitor as a power supply filter? I'm updating a vintage Heathkit capacitor checker that I use regularly for re-forming electrolytics, and its power supply filter is currently two 40-uF 450-V in series, without balancing resistors; applied voltage is nominally 600 V DC. This hasn't given any trouble, but I'm uneasy about its future. Now...

I got one of those. Today, I tried to set up two oscilloscope probes. (the frequency compensation capacitor) I noticed the following...

I got one of those. Today, I tried to set up two oscilloscope probes. (the frequency compensation capacitor) I noticed the following things in bitscope-dso: when adjusting the cap, the waveshape doesn't change, but the amplitude does. at 250kHz it's almost triangles regardless of capacitor setting. 50kHz looks acceptable. I am also not sure what sort of filter it has and how to turn i...

Ok, simple circuit: Schmitt inverter, 10K resistor from output to input, 1000pF capacitor from input to ground. Vh set to about 20% of Vhigh....

Ok, simple circuit: Schmitt inverter, 10K resistor from output to input, 1000pF capacitor from input to ground. Vh set to about 20% of Vhigh. Should happily oscillate but I get the error message "Time step too small". Also there is a noted dip in voltage down to about 80%, something which should even be possible with a digital behavioral device. What gives? How can I fix that and make i...

Years ago we had threads about the ugly but seemingly simple scheme to get 12V DC at 5mA, etc, with a film capacitor straight to the AC ...

Years ago we had threads about the ugly but seemingly simple scheme to get 12V DC at 5mA, etc, with a film capacitor straight to the AC line. We said, gotta have a series resistor to minimize the startup inrush current. Does anybody recall a specific instance of this scheme being used commercially? Paul and I are days away from turning in the manuscript on our new x-Chapters ...

https://youtu.be/FSwZQtqWyHw Can that whining noise be easily eliminated? I am assuming its origin is easy for some to guess. It uses...

https://youtu.be/FSwZQtqWyHw Can that whining noise be easily eliminated? I am assuming its origin is easy for some to guess. It uses brushless motors controlled by an "electronic speed control" (ESC). There is a large cap across each ESC supply plus and minus. I tried adding a 1000 ?F low ESR capacitor on the battery input but that didn't help. Thanks.

Could some electronics guru here please help ? What is the best way to select a transistor for an oscillator ? Consider a Colpitts oscillator...

Could some electronics guru here please help ? What is the best way to select a transistor for an oscillator ? Consider a Colpitts oscillator running at 5 MHz. The following are the analysis steps. 1. Select a value for the LC tank capacitor C1 = C2 = C 2. Select a load e.g., R=50 Ohm 3. To start oscillations, gmR > C2/C1. In this case gmR > 1 4. Using the oscillation frequency and

Modern buck regulators seem to have way too many features that I can't turn off or customize. The otherwise very nice AOZ1282-1 snookered me...

Modern buck regulators seem to have way too many features that I can't turn off or customize. The otherwise very nice AOZ1282-1 snookered me by having a 600-us fixed short-circuit protection interval--it wouldn't start up into a 220 uF capacitor, even with a very light load. Fortunately, switching to 22 uF fixed it, and I had some with the right footprint. And then many go into stut...

My latest project is a battery management system (BMS) that can accurately measure cells in a lithium battery pack, and also perform shunt...

My latest project is a battery management system (BMS) that can accurately measure cells in a lithium battery pack, and also perform shunt balancing and possibly charge shuttling to balance the pack. I would also like to be able to use it for a pack of four 12V SLA batteries. A DG408 could be used to select up to 8 cell voltage taps from nominal 3.2V (LiFePO4) or 3.7V (Li-Ion), with a ma...

I intend to build a classic spark gap Tesla coil. I understand the value of the timing cap must be selected with reference to the resonant...

I intend to build a classic spark gap Tesla coil. I understand the value of the timing cap must be selected with reference to the resonant frequency of the coil. I was wondering what would happen if I was to custom build (wrap) a tubular cap, from al foil and mylar, and slide it _within_ the TC's secondary so both are on the same axis. Would this configuration tend to make selection ...

I would like to experiment a bit with magnetic parametric amplifiers. For that purpose, I believe I need a 200kHz sine wave generator with a...

I would like to experiment a bit with magnetic parametric amplifiers. For that purpose, I believe I need a 200kHz sine wave generator with a watt worth of output power. My obvious choice was to construct a current-fed resonant Royer oscillator. For a 1nF tank capacitor it implies a 633uH inductor (2x5 turns on a 6400nH/turn^2 way to big toroidal core), 2x ZTX851, a 100k base polarization resi...

Spice Model Needed... Does anyone know of a _device-level_ Spice model for a 74HC05 open-drain inverter? I could write one, but there's not...

Spice Model Needed... Does anyone know of a _device-level_ Spice model for a 74HC05 open-drain inverter? I could write one, but there's not a lot of accurate specification information out there. I need a device-level model since my client's application dumps a capacitor. ...Jim Thompson -- | James E.Thompson ...