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I'm working on another project with extreme EMC requirements as per various notorious military EMC standards. Civilian product but for military use, and as such subject to the toughest levels of co...
Suppose I have a planar PCB transformer. The primary and secondary coils are printed on different PCBs. The core is inserted through these PCBs to link the two coils. The primary is at a low voltag...
In the field of DC/DC conversion, one can build a synchronous DC/DC converter (also referred to as synchronous rectification). This practice involves replacing a diode with a MOSFET switch. As far...
I have generated flyback convertor schematic by TI's Webench Power Designer. Parameters: universal AC input (85-265V AC) 5V, 2A output isolated UC3843A controller Basically I understand f...
Inside a op-amp after the stage where the differential signal is converted to single ended , there is further amplification of the DC signal.For AC signals there is a capacitor parallel to the tran...
I was hiking around the Berkshires in western Massachusetts yesterday, and came across this metal panel where some power lines were crossing a ridge: The panel is a few meters wide, and appe...
In all descriptions of how (non-FET) transistors work I've seen, there is an inherent symmetry: There's either an n-doped layer between two p-doped, or a p-doped between two n-doped, and the descri...
When using through-hole ("THR") connectors on a multi-layer PCB, I frequently notice problems with the ground pins, when these are connected to the ground plane(s) through various "thermal relief" ...
Modern CAN transceivers like MCP2561FD that support CAN FD with high baudrates come with an optional feature called SPLIT, which is to my understanding a reference voltage output pin used to give a...
I am designing a PCB with somewhat limited space. To save space, I am placing some vias on component pads. However, I am not sure if this is a good practice in PCB design. As far as I understand, t...
I have a Rigol DS1104 oscilloscope. Last week I stood up quickly from my table and saw a spike on the scope. Right now all the channels have a DC offset when probe is connected to ground or unconne...
I want to design a simple battery charger using MCP73831/2. This chip has a 3-State state pin according to the table below: I have a 3.3V MCU and I want to connect this pin to a GPIO. The MCU is...
This question is related to my previous question. I want to drive a brushed DC motor using H-bridge. To power the motor two 18650 cells will be used in series. The issue is that I want to limit th...
For high-speed digital communication busses, what attributes do you generally advise to add to a PCB to help with validating the communication bus as well as troubleshooting the design? In particu...
Do micro-RF connector mating crimp connectors are ever sold separately together with a crimp tool? For example this I have looked through a lot of pages, and can only find PCB connectors + cable a...
Hi guys so recently i was looking for a mosfet and a gate drivers and between a lot of their specification the rise/fall time and Turn-On/off Delay Time sometime it called propagation. My question...
I am using two 18650 cells in series to power a RC car. Is the voltage goes below 6.2 V, the battery should be disconnected to prevent over discharging the battery. At the same time I want to imple...
I have just started learning about thermal noise in op-amps and while studying could not find if the noise given in op-amps data sheets is random sample to sample regardless of the time interval be...
I am looking to improve my knowledge of embedded systems programming, specifically regarding microcontrollers and embedded Linux systems. A lot of the information that can be found regarding C/C++...
Power switches used in automotive are usually rated to withstand clamped load dump events, of the 35 - 40 V peak variety. AFAICT there are two main clamping mechanisms - first one for the logic par...
I have seen multiple sources on the web discussing what they call concentric twist harnesses. It boils down to having a wiring harness built in layers, where each layer is twisted around the previo...
I've heard that arc welding is getting done with low voltage. I believe arcing requires high voltage. Then how is arc welding done with about 50 volts? I thought we need kilovolts for arcing. Why? ...
EMG consists of an electrode gel skin interface, op-amps with a certain gain and an ADC. Question is in the context of passive electrodes. What are the essential safety features of such types of h...
The plugs for microphones and for earphones are the same, however their functionality obviously is quite different. Now because of the same plugs it is easy to insert one of them in the wrong socke...
Most CAD packages use a "symbol" and "footprint" library approach when it comes to designing schematics and PCBs. Some (like recent versions of Altium) have "component" libraries where symbols and ...
Got a question about hazardous breakpoints in real-time firmware. Does C have a mechanism which lets me mark a section of code such that breakpoints are somehow ignored or not allowed just in that...
If the external power supply to a device fails, and I can't get the exact model, what do I need to specify to get the right replacement? I can re-use the old supply's connector, but what about the...
I'm trying to drive a relay according to a 5 V digital signal, using this circuit: It works for a while, but then the transistor fails. When I replace the transistor, it works for a while again, ...
I'm trying to understand a circuit for driving a LED found on a board I purchased. Below is the circuit driven by an I/O pin (HS2) of a small 3.3V processor. The HS2 pin is driven by the I/O wi...
I have seen pi-filters using chokes, ferrite-beads, and plain inductors as the L-element What are the main differences between them? when use one or other?
If you search through the electrolytic capacitor offerings from distributors like Farnell, RS, Digikey or Mouser, you find that the maximum life-time rating is commonly quoted as 5,000 or 10,000 ho...
What benefit has a differential amplifier when measuring the signal from a sensor that is remotely located such as in this example: - Why can't I use an arrangement like this: -
I am designing a 4-layer PCB that has both analog and digital circuitry throughout it. The analog section involves high return currents as well as ADCs sampling the voltage across sense resistors a...
In theory (I mean in my engineering curriculum) I never found a diode in a mosfet symbol but in datasheets there is a diode called as body diode in both pmos and nmos.Please explain its significan...
I don't know whether this question is on-topic or not but answering this helps a lot of future electronics entrepreneurs like me understand how the product design and development time estimation ta...
I have a handheld ARM Cortex M based device, which has a USB input port. The product is battery powered and there is no metal chassis. We are going through CE testing, and are having ESD issues a...
Sometimes cables between utility poles make a loop and do a U-turn. What is the purpose of such loops? The loop I'm asking about is in the lower set of wires towards the left of the picture. The...
Simple thing that I realized I should know but do not -- when is an MOV preferable to a TVS diode (with some associated network to really make it work, in both cases)? Is it even something to routi...
My question is trying to understand if there is an effect on the switching time, on both turn-on and turn-off, between the following configurations. A mirror set up to switch a current, and there ...
Assume that I have some generic antenna connector, followed by a pi-filter/50ohm impedance matching components, then a DC blocking cap (as per the RF switch recommendations) and then a RF switch fo...
I have been observing these little cases hanging to the wires from a long time. They are almost everywhere here in India, but I was unable to find out what they are. I am not sure whether they are...
Application notes for microcontrollers or other ICs that have an internal 10M/100M ethernet PHY module differ in their requirements for the external interface components. It seems that the PHY des...
While doing some reading on RF designs I ran across this paragraph: I have never designed an RF circuit, but all the PCB trace antennas I have seen on development boards are square. For example,...
Is the cell voltage (at a modest charging rate) mostly determined by thermodynamics on the electrode surfaces and resistances of electrolyte and electrode particles, or there is a non-negligible ki...
The question being asked Ultimately, I want to know why the output voltage wasn't the expected (via calculation) 11.72V when the estimated drop-out voltage at the ~0.1A load was about 200mV. The i...
Background. I have a legacy battery system that is comprised of twenty-four 12V Li-ion battery modules (self-protected), enclosed in a shell with the charging connection provided as a common groun...
I have a problem which I don’t understand how to solve. I have this 2-bit adder, but when I select A1AO to be (11)2 3 and B1BO to be (11)2 3 and run it on Logisim it doesn’t show me 6. Instead it s...
I am designing a DC/DC converter in the control loop of which a transconductance amplifier (OTA) is used. This part of circuit looks like this: To determine the needed characteristics, I am usin...
Intro Hi everyone, I have a question about the practical use of a PTC (positive thermal coefficient) resettable fuse. I've never used one before, but I'd like to add one to a DC motor circuit to p...
I'm wondering what's the most correct term (if any) to use for "switching noise" of a radio transceiver? By that I mean the spikes that originate from turning the power amp on/off while switching b...
