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H: Equivalent diagram of a transistor using a Zener diode
In Horowitz The Art of Electronics on page 72 there is a schematic that provides an "ohmmeters view" of a transistor (see below.) In the description it says:
The base–emitter and base–collector circuits behave like diodes in which a small current applied to th... |
H: Trouble solving a specific KVL KCL question
Now I know this is newbie-ish kinda question but I was going over the basics of KCL and KVL, and encountered this problem:
For 1., I determine the drop using Ohm's law, ie. 2V
for 2-4 things get confusing. I apply KVL and KCL as follows:
For KVL1: I2R2+Vs1-I3R3=0
=> -... |
H: 2nd order high pass filter with two real poles
I want to implement an active analog high pass filter, which behaves as a high pass filter implemented by a capacitance, an inductance and a resistor in the following way:
simulate this circuit – Schematic created using CircuitLab
Which gives the follwing transfer fun... |
H: Need a 110V switch that turns on with low current
I’m good with electronics, but bad with terminology. Basically, I need a switch of some sort that can pull regular power from my house (110V) to power a device that normally just plugs into the wall, except I need the switch to only close/turn on when low voltage (5... |
H: LED drivers suitable for groups of LED lamps
Summary
Replacing MR16 SELV AC halogen spots with 12VDC LEDs. The halogens have individual drivers - need advice replacing these with (fewer) DC equivalents.
Setup
2 rooms with AC 240V supply, 6 lamp + 3 lamp
12VDC MR16 LED spots, 5W 660mA
These are smart - powered all ... |
H: System of linear equations for node voltage method
I have the following circuit (see Picture 1) on which I have to apply the node voltage method:
I have to use the steps which are described in the script that the prof. gave me.
The first step is to change the power supply with the series resistor \$R_2\$ into an c... |
H: Case-less Power Triac Part Number Identification
I am trying to identify the part number of this high current (20A) triac. It was originally covered in potting, and it appears to have four pins (2 power, 2 control). It would appear to be something like this BCR30GM except that it does not have a case. The power tri... |
H: How to shift 3.3V to 5V with 3.3V provided only
I am trying to control 5V LED using ESP32's 3.3V GPIO. I researched voltage shifting using NMOS but could not get it to correctly output 5V when simulated in Tinkercad.
Is it possible to accomplish this without a 5V supply? What am I doing wrong here?
Edit:
LED I got... |
H: Finding frequency response of inductive EMI sensor
I'm building an EMI sensor and trying to understand how it's done with the Elektrosluch. Here's the full schematic but this is the part I'm concerned about:
simulate this circuit – Schematic created using CircuitLab
I want to find the frequency response analytical... |
H: DC-DC Converter Remote ON/OFF logic levels
I'm trying to interpret the datasheet's description of the positive logic remote ON/OFF pin on this VQE50W-Q24-S5 DC to DC converter. It looks like it's ON when given 3.5 - 75V, or unconnected. Ok, that's pretty easy to understand.
But then it's OFF when... less than 1.2V.... |
H: Square wave generator without op-amp
I am trying to make a square wave generator but don't have an op-amp nor the PNP transistor to do it. Is there any way that works? I have tried using this one:
simulate this circuit – Schematic created using CircuitLab
but it is always on.
AI: It is already working and you can ... |
H: Why is a LED with no resistor not a dead short?
From research you read on LEDs they need resistors to limit current.
But from experimenting, it seems to draw current given the correct voltage.
Even if I put a 5mm LED between 5 V and ground on an Arduino, it doesn't pull runaway current like a dead short. It just ru... |
H: In LTspice, how do I create a voltage source with a piecewise frequency dependence in an AC analysis?
I would like to run an AC analysis with a voltage source whose voltage varies with frequency according to the following piecewise plot:
I've heard it's impossible to have a frequency dependent voltage source in LT... |
H: wGate driver working-Parallel NFET
Reference
With context to the following image.
From the input pin, which can be interfaced with CMOS logic. The highlighted enhancement type PMOS & NMOS pair acts as an inverter pair, right? (basically switching action, when PMOS is ON, the NMOS would be OFF & vice versa) this wo... |
H: Cut off frequency of a passive second order low pass filter
I was trying to do a simulation for second order low pass passive filter, and the equation of the cut off frequency is $$f_c=\frac{1}{2\pi\sqrt{R_1C_1R_2C_2}}$$
when I calculate it on the values of this circuit I get $$f_c=1591Hz$$
but when I use OrCad to ... |
H: How to understand the DC-biasing and the HPF circuits in the top-left corner of OPA1671 datasheet's reference application schematic?
I'm looking to understand the chosen values in this reference design and whether they can be improved, particularly the biasing DC circuit and the high-pass filter for the electret mi... |
H: Can someone give me an example of how a low or high pass filter is used in practice?
I understand the theory and math behind electric filtering systems but I don't understand how they can actually be used in circuits. Take an RC low pass filter as an example. For low frequencies, the input voltage will approximatel... |
H: Using Timer Interrupts Instead Of Delays in PIC Microcontroller
I have this task where I have to use timer interrupts intead of delays (for efficiency purposes) in this 7 segment display circuit with PIC18F4620.
Here is the circuit:
Display is common anode.
I would normally write the code like this and the output ... |
H: A bit of confusion with DRV8210DRLR motor driver
I am working with DRV8210DRLR motor driver, mouser says it is a half bridge controller, texas instruments that it is a H-bridge. I require to spin motor and be able to change direction, so I assume I need full bridge controller. So first question is are there differe... |
H: Is it possible to produce 30W (5V 6A) using a flyback topology without opto-isolation?
The circuit steps the voltage down from POE (class 4) input to 5V 6A
The circuits I have found so far use opto-isolation to regulate the feedback voltage (for 5V 6A). I'm wondering is it feasible to use the Auxiliary to regulate ... |
H: What is the maximum reasonable cable length for a humidity sensor?
I have an ESP32, and use capacitive soil humidity sensors to check the humidity of my plants. They get shipped with about 15 cm of cable attached.
What is a reasonable/safe cable length I can use before it gives unrealistic readings? It is powered w... |
H: What is the design reason behind these components?
I have some questions regarding the comparison of these two circuits. Both produce current noise through the first reverse-biased transistor. That variable current enters through the base of the second transistor, affecting its collector's voltage.
What is the purp... |
H: Modelling a capacitor on a PCB
I want to design a "PCB capacitor". The goal is to detect the permittivity of the material surrounding the PCB. I am unsure how to design the electrodes of the capacitor in order to have the highest sensitivity. It will be a two layer PCB.
I basically have three designs in my mind, se... |
H: How do I know how much a kWh costs me if I have my private generator
I have a 10 kVA generator and its efficiency is approx. 90%
How can I know the cost of a kWh?
Estimate the price of diesel as $2.5 a liter.
AI: I have a 10 kVA generator and its efficiency is approx. 90%.
That's impossible. No internal combustion... |
H: Wrong frequency response of an active HPF filter
I am trying to simulate an active high pass filter on OrCad, but the frequency response of it looks like a band pass filter, does anyone know why ?
AI: Sure, the mystery part you used does not have the bandwidth or slew rate to be capable of 20V output amplitude at b... |
H: Looking for a component that accepts a broad range of discrete values (e.g. 0 to 50 VDC) and outputs a LOGIC HIGH; otherwise output is LOGIC LOW
I am looking for a component that will accept multiple discrete values ranging from 0 to 50 VDC, but it doesn't have to be 50 VDC. I am looking for a broad range. This ra... |
H: How to describe, in a schematic, grounding to the base/body of a potentiometer?
I am working on updating a guitar project I did many, many years ago. I mean, I could just do a 'symbolic' drawing of the wiring itself, but since I have more experience now, for my records I'd just like to draw up a formal schematic.
M... |
H: Voltage regulator LMR33630 doesn't work, asking for circuit review
I've put LMR33630ADDAR voltage regulator into a PCB with this circuit:
It's slightly different from the example from datasheet:
PG isn't connected, CFF capacitor absent and feedback resistors are 10k vs. 2.49k. I see no issues with these differenc... |
H: Using clothesline steel core wire rope for AC and DC
As I am currently in a war zone, I don't have many options for cabling.
I found this clothesline (steel core plastic wire rope) that appears to be one mm of diameter (steel core diameter.) 13 meters of it measured 7 ohms resistance.
Edit: It is 3.8 Ω and not 7. T... |
H: IRLML9301PBF as high side switching for 5 V, 2 A load from a 3.3 V uC?
Circuit:
simulate this circuit – Schematic created using CircuitLab
I would like to cut off the power to my APA102-LED-strip during uC sleep -
as the standby current of these strips is relative high.
The strip is directly powered via the 5 V fr... |
H: pulse generator MATLAB
How to create a rectangular waveform with amplitude 18 to -3 using pulse generator? If I put 18 as the amplitude then the wave is between 18 and 0. How do I change that to 18 to -3?
AI: Make the amplitude 21 volts and subtract 3 volts DC from the pulse output. |
H: How to define the input common-mode voltage in this circuit?
I am trying to simulate the circuit below (from this paper) at the transistor level using a 0.18um, 1.8V process. The circuit serves as an amplifier for recording neural activities, and uses 2 capacitors (C1) to block DC offset and set the gain.
The OTA ... |
H: Working of analog current monitor
Reference
I couldn't understand the implementation of current monitoring for this IC.
"The current source at IMON terminal is configured to be proportional to the current flowing through the RSNS current sense resistor."
Per my observations, there is no current source at the IMO... |
H: Is this a possible Leakage current problem
I have a question about the connection circuit between µ-controller and KSZ8851SNL.
Are the CSN and SO pins of the KSZ8851SNL tolerant inputs?
When Q1 is off, LAN3.3V was 0.9V in actual measurement. I think this is due to the current flowing through the internal protectio... |
H: Need help understanding the basics of electronics
I would like to state that I'm a beginner in learning electronics by reading my first book on electronics I'm lost and would like some help. I even included an image that would hopefully help my case.
By learning series and parallel circuit. What confuses me if we h... |
H: Altium: What do the different options under Properties (panel) -> General (tab) -> Type, mean?
Here is the image of the drop down list:
The "standard" is the default option. But what does Mechanical, Graphical and other options do?
AI: I might introduce to you the F1 key on your keyboard. Highlight the offending ... |
H: Can I use a power bank of 5 V/3 A to power an Orange Pi 5?
I'm trying to build a portable PC with the Orange Pi 5 16GB RAM model with a touch screen and powered by a solar power bank.
I saw that the Orange Pi 5 requires 5 V/4 A to be powered, but I can't find solar power banks with 5 V/4 A, only some with a max. of... |
H: Does the remote control we have at home work with infrared (IR) frequency?
Picture source.
I was told by my AC's technician who several times came to my house to fix my air conditioner, especially if it got problem with the remote control or the board on the AC equipment. Once he explained how to see the infrared... |
H: LED PCB footprint with non-symmetrical pads
This question is related to the LED component HL-AM-2835H489W-S1-08HL-HR3 from HONGLITRONIC. The datasheet for this part can be found here.
This component has a SMD2835 SMD package that I have not used before. Please see the footprint drawing given in the datasheet page 2... |
H: For sufficiently low duty cycle, can you get away with driving SCR above rated current as long as A^2 * s are maintained?
I'm wondering if the A^2-s rating of an SCR is what ultimately decides whether a given current for a given time is okay, even if the data sheet does not list such a number.
For instance, right n... |
H: How do you use an RC filter on an LNA output to reduce unwanted noise?
We designed two low noise amplifiers, one at 144 MHz and another at 440 MHz using this LNA; each design is tuned for the particular band. We noticed amplification at 440 MHz is clean and crisp, but amplification at 144 MHz is scratchy with FM au... |
H: PCB manufacturing process: covering holes with soldermask
The PCB manufacturer is asking
These highlighted green areas (they are openings on the bottom soldermask layer) will be exposed in the bottom layer and you required us to cover the bottom layer with solder resist in the notes.
We suggest to delete these ope... |
H: LED PCB footprint with non-square pads
The question is related to the datasheet for LED part number MHT151WDT. It is manufactured by Lianyungang Meihua Electronics Technology Co. Ltd. The datasheet can be found here.
The pg. 2 in this datasheet gives this drawing as guide to create the PCB footprint:
There are two... |
H: Best Processor for WiFi to GbE Bridge
I’m looking to build a WiFi to Ethernet Bridge, and did an initial test with a Raspberry Pi 4B. I noticed the CPU was always using less than 10% processing power, which makes me question whether or not I need a full Linux computer for such a computationally simple task.
I reali... |
H: Very low frequency counter
I currently teach an introductory course to electronics that is mostly analog, but can incorporate some digital circuits. On our function generators, we have an arbitrary heartbeat shaped waveform and I thought it would be nice to try to make a heartbeat counter.
Obviously, the easiest ap... |
H: How does CANopen support many devices with limited PDO
I'm pretty new to canbus and CANopen and can't seem to wrap my head around PDOs. I understand that a PDO must be defined and agreed upon ahead of time, and that multiple OD entries can be packed into a single PDO. What I'm not understanding is how only 4 PDOs c... |
H: 10/100 Ethernet Routing Review
I know it is a big favor to ask, but this is my first ethernet design, so could you provide input on the routing from connector to mag and from mag to PHY? Is it fine or how can I improve it?
Really appreciate it!
And this is the schematic for reference:
AI: 10/100 Ethernet is wonde... |
H: Exposed pad and ground
I'm using this device - ATSAMD21G17A
While I measured the connection between the exposed pad and ground, they seem to be unconnected.
When I went and check on section 10, problem 20, on page 30 of this Checklist, I found the below:
Which effectively says us to connected the exposed pad to gr... |
H: Connecting TTL-232R-5V-PCB to STM32F103C8T6A bluepill via OTG and installing boot to this STM32 microcontroller
I have TTL-232R-5V-PCB and STM32F103C8T6A bluepill board. I am working on installing bootloader to this bluepill board on that way, I have searched on the web about it but all people connected them via ju... |
H: Continuous current limiting with hot swap controller
I am using a brushless DC motor which has its own integrated controller (nominal current 4 A at 24 V). To protect the motor, I'm willing to implement some current limiting circuit (e.g. with maximum allowed current 5 A).
The TI LM5069 hot swap controller (link), ... |
H: PCB fab questions: Surface finishes and reasonable source for a single board
I've designed a unique Stylophone-type keyboard. I've prototyped it on Masonite with copper foil tape. Now, I'd love to get a slick PCB fabricated. It's a large board, but I feel like, as a hobbyist, I'm just a complete annoyance to the pl... |
H: I need to make a makeshift thermocouple given limited resources in the third world
I'm living in a part of the world where scrap electronics are hard to come by. Recycling these are big money in the impoverished SEA region I'm living in.
I have a Fluke 289 with a type K thermocouple that is reasonably precise. I re... |
H: What do dashed lines mean in the schematic?
This is a "6-pin self-locking push button", but I don't know what dashed lines mean (those that are in the schematic).
AI: It looks like the solid lines are the connections in the "normal" or unpressed state and the dashed lines are the connections in the pressed state. ... |
H: Value of output capacitance via Miller approximation
There is an example in Razavi's textbook (Design of Analog CMOS Integrated Circuits 2nd edition) demonstrating the Miller effect/approximation, shown below.
As you can see the example claims that the Miller output capacitance is given by \$C=\frac{C_F}{A+1}\$. H... |
H: How does MOSFET gate-drain capacitance behave?
When a voltage is applied to MOSFET drain, Cgd acts as closed switch and for a short moment raises the gate voltage to drain voltage. Is this statement true?
In Falstad circuit simulator (see simulation here), I added Cgd to simulate a real MOSFET and these short burst... |
H: Why do I need to ground GP0 to enter programming mode in ESP8266?
I have an ESP-01 chip. I found out that I need to ground the GP0 pin to enter the programming mode to flash a program to the chip. I can't find anything in the ESP8266 datasheet that documents this. I'm wondering how we know that we need to ground th... |
H: Correct orientation of EMI filter
The label of this EMI filter seems reversed to me because in the diagram there are three pins on the side of the line but the are two wires on that side of the device.
Is there a way to determine the correct orientation? I did some tests with a LCR meter but I measured around 100 ... |
H: What happens if a dependent current source has a negative value?
When I try to solve some circuit exercises, I receive a negative number for the dependent current source (meaning the direction of the source is wrong, maybe).
Is this a wrong solution or is nothing wrong (meaning the direction of source draw in the ... |
H: Are lithium-ion battery cells' maximum discharge ratings based on heat?
For any given lithium-ion battery cell, would I be able to discharge more than its rated maximum discharge value provided that it's for a brief time and/or the heat does not rise up and be sustained by a certain amount?
Like for instance if I d... |
H: Can you use a diode to cancel the body diode of a MOSFET?
From what I understand, MOSFETs inherently have a diode between the source and drain known as a body diode. If I were to use an nMOSFET as a low side switch, would it be bad to have a diode between the load and the drain of the MOSFET? What effect would it h... |
H: Signal saturating after transistor amplifier
I'm trying to amplify this noise coming from Q1 but it looks like it's saturating at the collector of Q2 (as you can see in the image). How can I resize the resistor values such that the signal does not saturate?
I have 11.8V at the collector.
simulate this circuit – Sc... |
H: Spice transient vs AC models
In process of designing an electronic or a mechatronic system, we take into account AC analysis and Transient analysis of that system. In my case, I want to design a speed and position control system for a DC motor. I went through the theoretical analysis of my system by taking into acc... |
H: TP4056 ON/OFF Switch not fully working
I was testing the PCB of an electronics design (attached) when I noticed that when I put SW1 into the "OFF" position, there was still a small voltage (~1V) on U37 (MT3608 boost converter) which was boosted to about ~3V and as such my microcontroller did not turn off (I disable... |
H: Virtual ground in non inverting op amp
Why is the voltage not equal in inverting and non-inverting terminals in a non-inverting opamp? During the derivation, we take two different V1 and V2. Why doesn't virtual ground apply here?
AI: In both of the circuits below, \$V_Q = V_P\$:
simulate this circuit – Schematic... |
H: What MOSFETs should I use in this configuration?
Here is a configuration of MOSFETs which I believe allows for two different sources to supply power to the same load.
This diagram was originally found here.
The primary source is connected to the top pair of MOSFETs (labeled VCC_USB in the diagram.) The secondary s... |
H: Easiest way for a beginner to design and make a custom printed circuit
I've used a prototyping board to successfully build an Arduino based system for a custom purpose
I would like to transfer this design to a custom PCB (using a service like PCBWay, for example,) so that I can have a smaller and neater circuit boa... |
H: Driving a 12-to-24 V P-channel MOSFET with TTL
I'd like to control up to 16 motorized valves with an ESP32. I'm using 74HCT595 shift registers (5 V outputs, 3.3 V input logic) to drive 12 V relays via NPN transistors. But the relays are pretty overkill and I'd like to replace them with MOSFETs. Since the motor valv... |
H: Cannot stop Microcontroller's Hardware Timer from running
I'm using an Atmel ATMega8 microcontroller to control a stepper motor. (Datasheet).
Timer1 (a 16-bit hardware counter) is used in CTC mode to modulate an IO pin to provide the stepping signal to the motor controller. This part works fine and I'm able to ad... |
H: Why is this point giving me 8.3 V?
I am trying to find the voltage at V2 using the wire label in the Qucs-s simulator, powered by Ngspice. I have used Ohm’s law (V=IR) to work out the the voltage across R1 which was 1.66 volts;, but the simulator is claiming that there is around 8.3 volts at V2.
I also tried usi... |
H: What is the ⎓ symbol (which looks similar to an equals sign) called?
What is the ⎓ symbol called, which looks similar to an equals sign with the bottom line broken into 3 dashes, and is used in consumer electronics?
AI: This is not an 'Equal' Sign in math-terms.
It's a sign used by convention to denote DC-systems.
... |
H: Universal AC Motor Brush Rotation Angle
Considering adding reversing capability to a Porter Cable 690LR (router) universal AC motor for use as a spindle motor. Yes, there are better alternatives but this is to finish someone else's wood-CNC project. 120 VAC, 60Hz, 11A, 27,500RPM, 1.75HP. Typical series-wound mot... |
H: Solar charge controller for lithium batteries
My project is a solar powered RC car with the ESP32. Currently, I´m looking for a solar charge controller. I have two solar panels that deliver 3,5W at 6V. I want to charge Li-Ion or LiPo batterys. I need about 3A/ 5V for my project. My idea was to use the TP4056 charge... |
H: How can I control PNP and NPN transistors together from one pin?
I'm trying to understand how it is possible to control a PNP and a NPN transistor simultaneously from one controlling pin.
My issue is that when the INPUT pin is left floating, the transistors drive each other and both go into conducting mode. When I... |
H: LTspice simulation for an inductor doesn't output the correct current value
I have a very simple circuit in LTspice for an inductor. The power is an AC voltage source with 50Hz and peak voltage is 640V. The inductor is 0.1H. According to the inductive impedance equation X = 2fL, the impedance is 31.415Ω and the ... |
H: Altium: Deleting the "room" object in the PCB view
When I carried out "Import changes from ..." into my PCB view, the components from the only schematic were all imported into it. However, it also created a box that has same name as the schematic file itself. Please see this image below:
I am not completely sure w... |
H: ATtiny85: Accidentally applied reverse voltage
Now it happened. It was dark and while I was coding I accidentally put the ATtiny85 inverted into the breadboard, so I applied +5 VDC to GND instead to VCC.
The power came from an UNO R3 which was powered by USB. Immediately after that I heard the Windows USB sound so ... |
H: Diode configuration of BJT
I came across this configuration while trying to understand the remote temp sensing ability of the TPS4811.
It seems as if the diode pin voltage is responsible for turning on the BJT. V(BE) being >= 0.7V. The same is also controlling the Collector current & Base current.
How exactly is th... |
H: Which reverse polarity protection is better and why?
You can find two such circuits using a diode that protects against reverse polarity, i.e. against wrong power connection.
I wonder what is the point of using the D2 diode, since the current flowing through it will damage it - at least that's what the simulation s... |
H: Using BS270 MOSFET as Temperature Sensor
I have previously asked a question about using thermocouples to maintain a temperature range of 36-39° inside an insulated and dry environment.
The more enlightened engineers advised I look into using either a semiconductor device or an RTD instead.
Parts availability is lim... |
H: Why is DutyCycle not respected in code? Where I am wrong?
I have a PIC12F1572 and a push button (not exist in schematic). I want to get PWM on RA4 when the button is activated. The button is connected to RA2.
I set 50% PWM (13333 from 26667.) When the button is activated I get small PWM (under 1%). When the button... |
H: Discrete OPAMP problem
I designed an opamp using discrete components (no specific purpose).
This is my circuit:
Real circuit:
I test the opamp by simple voltage follower circuit. Everything seems right.
Yellow: input signal. Blue: output signal. They are almost identical. Therefore, they look like single sine wav... |
H: Computing the value of the quiescent operating point
Сan you help please with solving this problem?
The circuit shown below is used as an amplifier
The value of the componets are Rb=470 kΩ om RC = 4.7 kΩ
Power supply Vcc = 12V
The transistor has Vbe = 0.6V β(Beta) = 80
Compute the value of the quiescent operating p... |
H: PI Controller or Type 2 compensator using SIMetrix/SIMPLIS
I have PI controller build around one OPAM (link:https://www.researchgate.net/figure/Schematic-diagram-for-PI-controller-using-operational-amplifier_fig2_338104251) and I want to simulate it in SIMetrix/SIMPLIS simulator.Knowing that SIMPLIS simulator does ... |
H: IPC 4671 Via Types
In Altium designer the via type can be declared as one of the follows:
I know about tenting. This is where a via is covered. This way it won't cut through the silk screen or solder mask. But why would a person ever need the other options tenting and covering, plugging, plugging and covering? Sur... |
H: Why can't USART in synchronous mode be full duplex?
I have read in many websites (for example Difference between USART and UART and Difference between USART and UART) that USART operates in half-duplex mode and UART operates in full-duplex, but they never explain why.
I don't understand what makes it not possible f... |
H: How can I stop a comparator from oscillating in a relaxation oscillator configuration?
I have a dual supply comparator and I want it to stop oscillating and output +12V with a single switch. I tried to connect R3 to +12V but it still oscillate with low frequency and like 95% duty cycle.
As the tile goes: How can I ... |
H: Output impedance of the crystal driver
My question is regarding the answers, one and two.
Both answers talk about the impedance of the crystal driver output.
I'm trying to understand how the crystal driver output impedance will be related to the load capacitors of the crystal.
The first answer has this, "The impeda... |
H: Impact of crystal's ESR on the working of a crystal
I'd like to know how important the value of a crystal's ESR is for the working of the crystal at the right operating frequency.
I went through this question which asks for the priority between the crystal's ESR and stability, but I couldn't get clarity from the an... |
H: Inside a 2N3904 transistor TO-92 package
I cracked open this 2N3904 transistor. I lack the means to test its function until tomorrow.
The die doesn't look like anything I've ever seen before. I'm not quite sure where the silicon is.
In your opinion, does the back half of the transistor contain silicon required to ... |
H: Why does this show as a syntax error on Verilog?
I'm a newbie to Verilog, and I'm trying to follow the few youtube videos I've seen that use vscode as text editor for Verilog.
However, I get an error in the Verilog file itself. Here's my code:
module test(A, B, C)
input A;
output B;
output C;
... |
H: Linear solenoid specifications
I want to buy a linear solenoid that has the following specifications in the Datasheet:
24 VDC
9W 100% Duty Cycle
18W 50% Duty Cycle
36W 25% Duty Cycle
90W 10% Duty Cycle
And the following force-stroke curves:
I have a power supply of 24VDC and 10A. Since I don't know the coil resi... |
H: Inductance of Two Primaries in Parallel
I need to verify the design of a prototype SMPS transformer. The transformer has two primary windings driven in parallel specced at the same inductance value (the transformer manufacturer suggested this, our initial handwound design used a single primary). When I measure each... |
H: Variable output voltage regulation - does this solution make sense?
I want to use a switching power supply that has a fixed 24VDC output. I want to add a simple circuit that will give me an adjustable voltage between 0-24VDC. The power supply allows the consumption of about 2A and I would like to have such a curren... |
H: FR4/PCB electrical permitivity varing over temperature and effects on trace matching, how much does it change?
I have a high speed design that runs at 1.6GHz, there are also matched traces on a 12 layer board. Now I would like to know if the design will function over temperature of a -10C to 50C range and if the el... |
H: Altium: Unable to select component that ended up outside of the schematic sheet area
So I use "Smart paste" to create array of copies, then I selected the whole block and moved it to the side. Altium correctly moved the block and placed some components outside the sheet area. No error message was given.
Now I am un... |
H: High voltage MOSFET linear regulator failure
I designed the circuit below for an FSAE electric vehicle, for which the rules require an HV-powered LED to be lit when the HV bus is above 60 V. In simulation, the circuit works very well.
In real life, when 400 V was applied (smoothly thru a precharge circuit), it blew... |
H: Altium: Place components along circular path
There are basically two pairs of 10 LEDs, each in 0603 package. I need to place both of them in a circular path at 36 degree apart. I need to try a few different circle radius before I finally how I want the end product to be.
In Eagle PCB, I could just run a ULP script ... |
H: How to achieve coherent sampling in practice
In the context of measuring a sinusoidal source with an ADC, coherent sampling (i.e. capturing an integer number of periods) allows the use of a rectangular window without spectral leakage.
How does one actually do this in practice?
I am testing a 16 bit ADC that is samp... |
H: Altium: Pour small ground plane inside PWR plane
I have a layer with a full copper pour connected to 5V. I need to have a small section inside of this that is connected to ground. Is this possible in Altium Designer?
AI: Multiple areas with different nets a plane layer are common in PCBs, and possible in Altium.
Th... |
H: Unbalanced Wheatstone bridge with a capacitor in the middle
I have to find the amount of charge stored in a capacitor after a significant amount of time when $$ R_{1}=1 k \Omega, R_{2}=8 k \Omega, R_{3}=4 k \Omega, R_{4}=2 k \Omega,C=1\mu F,V=10V$$ There is no charge stored in the capacitor.
I found that this circ... |
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