text stringlengths 83 79.5k |
|---|
H: Low-side gate driver consistently shorts VDD to GND upon circuit power-up
I am using the UCC27423DGN dual low-side MOSFET driver as a current sink in order to drive some piezo elements. In general the gate drivers I am using are inverted, so on a high pulse on the Pulse_A/B lines, the outputs Pulse_A/B_Out should d... |
H: LED still on when transistor is closed with Arduino
When simulating the following circuit, there is no problem. However, when I do it in real life, with a BC558 transistor, the LED stays on even when the Arduino is not sending any voltage.
The resistor going to the base is 20 kΩ and the one connecting to the LED is... |
H: Moving magnet frequency over a coil
It's my understanding that :
Changing magnetic field over a coil induce current in the coil itself.
Current running through a coil makes it magnetic. (To put it simply)
Can these 2 rules affect each other to reach a point of equilibrium, and if so, is there a formula to get t... |
H: Digital Counter not initializing to 0 or rolling over to 0
I'm trying to make a 3-bit counter using D flip flops that loops through the sequence (0,3,4,5,7) repeatedly.
So far, I've made a timing trace, block diagram, operation table, Karnaugh maps, rough circuit diagram, and implemented it in Multisim.
The se... |
H: Three-phase motor Delta/YY connection diagram and windings troubleshooting
I am trying to troubleshoot this 1.4 kW three-phase motor and I'm unsure how its internal windings are interconnected or whether they are shorted.
On the plate it says "Delta/YY 400 V", and I'm not sure what YY means. Most articles online d... |
H: Why does my SSR’s heatsink have a small positive voltage?
I have an SSR in open state, split phase 220 across the inputs (heater inline), for now ground is not connected to anything, but I noticed, I have ~6.5 VAC from the heat sink to ground. I checked and there is no path the multimeter can find between either in... |
H: Why do battery cells fail in groups?
I have been observing for a long time that battery cells seem to fail in groups that are in close proximity.
I agree that observing 3 cells in a flash-light is not a very ample set, but I recently had the chance to observe several boxes with close manufacturing dates that have h... |
H: How to use the "Sense Function" of RT9080?
I'm testing the RT9080 as a voltage regulator, and on the datasheet I do not have too much information on what the "Sense Function" is.
I have the circuit connection, but how does it work, and how to use it?
In my case I was expecting info that can help to get the state of... |
H: Data collector: how much power will my system use (Linux vs. RTOS)?
This is about a data collection device. It mainly contains a Linux operating system, various data interfaces such as RS232/RS485/CAN/SDI-12/RJ45, etc., and a communication module for 4G and satellite communication. Of course, there are some analog ... |
H: Where do I hook up a speaker in this schematic?
I'm working on a project that needs to drive a single speaker. I've used LM2879T chips in the past to drive two speakers, so I have a couple extra I'm trying to use for this single speaker project.
Since I'm using a single speaker, I've heard I should 'bridge' the two... |
H: Is my circuit ok, using an N channel MOSFET to switch a P channel MOSFET for a high side switch
I'm using an CP361 voltage protection to ensure 5 V, this switches an N channel MOSFET which then creates a link to ground for the P channel MOSFET.
The link to ground turns on the P channel MOSFET and allows power to th... |
H: IC for translating 5V to 1.8V I2C signals
Looking for an IC to translate between 5V and 1.8V I2C. I need to connect an I2C sensor with MCU. MCU I2C pins are pulled-up to 5V while the maximum voltage on the sensor's I2C pins is 1.8V.
AI: You could use 2 NMOS for bidirectional levelshifting of I2C. The cathode of the... |
H: Why is the air gap important in a flyback transformer?
Why is the air gap important in a flyback transformer?
How should we consider the equivalent circuit of a standard flyback transformer?
If we are going to wrap all the windings of transformer to the airgap what happens?
What is the difference between these tw... |
H: How to use isolated amplifier to measure voltage
I want to read the cell's voltage with a microcontroller, but the cell does not share the same GND with the microcontroller. I want to keep them separate. I read some suggestions for this problem, and I try to use an isolated amplifier (I.A). I am considering using t... |
H: PCB Review / Signal Return Path
I'm trying to design better PCB layouts and as for now only work with 2 layers boards.
My question is about the signal return path on this PCB, is the design in the "right" path or I'm doing something wrong?
Any feedback will be appreciated.
Thank you in advance.
Obs.: In this partic... |
H: Why is it that for most Bluetooth audio devices, you can't use them while charging?
Over the past several years, I've had many small Bluetooth devices. I'm not one to buy many of these and, some how, over the years I've been gifted decent "SWAG", portable speakers and they've all had one thing in common--plug it in... |
H: What is the function of this pin in this BMS schematic?
I am implementing my own 3-cells battery management system charger based on the BQ76920 but I have a doubt about the REGOUT pin, in the datasheet it says that pin is the output of LDO (Low-Dropout Regulator according to what I read).
In the typical circuit ap... |
H: VHDL: Counter occasionally does not reset
I'm using ISE Project Navigator 14.7 with a Xilinx XC95144XL-5TQ100C CPLD in conjunction with a LM1881 video sync separator. I've also got a 14.3 MHz clock. I'm trying to generate VSYNC pulses in response to the LM1881 FIELD line changing (and yes, I know the LM1881 also ... |
H: Why is the output voltage 5V when supply voltage is 18V?
I am building a headlight driver circuit for my solar car team at school. The circuit uses transistors to drive the headlights and an 18 V power supply. My HIGH and LOW signal is a 5 V signal and 0 V signal respectively. When I measure the output voltage it r... |
H: Having trouble understanding textbook explanation of "hot chassis" in full-wave voltage doubler vs half-wave
The textbook explanation is not doing it for me.
The half-wave voltage doubler shown in Fig. 4-27(a) offers some improvement in safety over the full-wave voltage doubler. Compare Figs. 4-24(a) and 4-27(a). ... |
H: How do I make a good frequency multiplier for a basic sound chip? It uses a DAC, so it needs a high input frequency for lower output frequency
I'm building a simple triangle-wave sound chip based around a 4-bit DAC. It works, but I have to have each individual square wave for each of the 16 notes (which are bass-ra... |
H: Why is this p-channel MOSFET blinker not blinking?
I'm not a professional electronics person, just enthusiastic about it so my knownledge is limited. I first tried this with a n-channel mosfet, and worked well:
But it switches negative, and I need a positive switch, so tried this with a p-channel mosfet but didn't... |
H: Need help understanding this UART to RS485 adapter circuit
I am trying to understand how this circuit works.
Below is the explanation provided in the manual I am referring to:
"Receiving data: P_TX is in idle state, which is high level, transistor breakover, RE pin of
SP3485 is low to be active. RO pin begins to r... |
H: SMD components and PIC microcontroller
I'am working on a digital clock project with a PIC16F877. I'm designing the PCB with Proteus. The PCB contains mostly SMD components and I don't have any experience with that so I have some questions:
Do SMD components work the same as through-hole components? Should I use th... |
H: Class AB Amp slight distortion at any level
I wanted to build an amplifier for a spare set of 4 ohm 20W speakers I have laying around. After three days of searching circuits on the internet and trying them out on a breadboard not having much knowledge in amplifiers, I've finally managed to piece together this circu... |
H: Driving high-side MOSFET with another voltage source
I am trying to create a negative voltage source with a high-side MOSFET using another voltage source which is 4 V higher than the MOSFET's drain voltage.
In the schematic Q3's drain has 12 V and gate sees 16 V pulses. In this design, is 16 V enough for driving Q3... |
H: How did my CO detector know it had reached EOL?
I was recently awakened by my CO alarm beeping. I take CO exposure very seriously and attended to the beeping immediately. It was not a CO concentration alarm, but rather an end of life alarm indicating that it needed to be replaced. Note that there is a different ala... |
H: Transistor not totally acting like a switch
I have made two different circuits that, to my knowledge, should give the same result if the transistor is acting like a switch.
The current "passes" through the first switch/transistor and "passes" through the last switch/transistor before going to ground.
Circuit with s... |
H: Equation relating alternating magnetic field strength to induced voltage in search coil
I have a search coil (loop area A, N turns) placed normal to an alternating magnetic field with equation B(t)=Bp.sin(2.pi.f.t), B=field strength at time t, Bp=peak field strength, f=frequency, t=time. What is the equation to fin... |
H: Is there any voltage regulation on this board from an Apple Trackpad teardown?
Board:
Teardown, with brief descriptions of the major chips below:
Red: Broadcom BCM2042 for Bluetooth connectivity
Orange: Broadcom BCM5974 touch screen controller chip
Yellow: SST 25WF020 provides 2 Mbit of serial flash memory
Blue: ... |
H: How does this siren circuit work?
I am a beginner studying electronics and I have recently learned about the 555 timer. My course includes the following circuit diagram:
The goal of this circuit is to have the speaker produce a siren sound, however, I don't understand how the second 555 accomplishes this.
I unders... |
H: Which is the correct way to connect the gate and pull down resistors?
There are two forms of connecting this two resistors
If in both cases Rg=1k and Rpd=10k which connection is better?
I mean, i know that in the first connection there is a voltage divider so Vin!=Vgs and in the second connection Vin=Vgs.
In the ... |
H: Equivalent electrical circuit changing and power balance calculation
I tried to change this circuit in three different ways, but the power balance is not the same. The least power balance that I got was ~50 W more and we need to find the balance between 0 and 5 W. Ignore the number 16 in the picture; it is the vari... |
H: What is the simplest way to adjust the input voltage for a linear regulator?
I have a garage door opener for which I need to replace the radio receiver. The opener outputs a DC supply voltage for a receiver at 34 VDC. The receiver has an input range specification of 12-24 V AC/DC.
I'm attaching a photo of the recei... |
H: 24 V input, three 5 V outputs DC-DC buck converter design
I would like to make a DC-DC buck converter which has 24 V input and three 5 V outputs, but a typical buck converter circuits have only one output. How to change it to three outputs without an extra chip? Is it even possible?
AI: Hmmmh you are up for a ride ... |
H: Finding Ve for a 3 input AND gate TTL circuit for different logic combinations
I'm designing a circuit that takes 3 24V input signals and pulls a 50 ohm resistor to ground when all three signals are high. My main concern is the voltages across different pins of the transistors for different logic combinations.
The ... |
H: What happens to GPIO pins that are not exposed in a (small) package?
In one of our projects, we use an STM32L071 MCU in an LQFP48 package. It exposes GPIO port pins PA0 to PA15, PB0 to PB15 and PC13 to PC15 on the pins of the package.
The LQFP48 package doesn't expose GPIO port pins PC0 to PC12. But I can still pro... |
H: Does the capacitance of a Schottky diode depend on switching frequency?
In datasheets they write '1 MHz' in the capacitance vs voltage figures. For example:
I suppose it is some sort of a standard to measure the capacitance at 1 MHz, but is there a dependence of the capacitance on the frequency or is it just the d... |
H: avr-gcc optimization deleting register writes on ATTiny402
I'm using avr-gcc (12.1.0, built with this script: https://github.com/ZakKemble/avr-gcc-build) to compile for the ATtiny402 and encountering problems with code optimization. Specifically, the compiler appears to be 'optimizing out' repeated writes to regist... |
H: Is AM29F040B CMOS EEPROM TTL Compatible
I can't really make any sense of the datasheet regarding whether the AM29F040B EEPROM can be used with TTL inputs, so wanted to ask on here.
It is a 5V CMOS IC, but there are mentions in the datasheet on page 20 (AM29F040B Datasheet). There are two tables showing TTL/NMOS com... |
H: Proteus Ares traces do not connect
I am trying to connect a Vcc pin to a power source in Proteus Ares, but it does not let me do anything different from what I designed in Schematic Capture.
How can I connect the selected trace to the Vcc pin? I could try and connect the Vcc pin in the schematic first but the probl... |
H: Cockcroft–Walton generator "charging" cycles
I am studying the Cockcroft–Walton generator and one question comes to mind.
Let's say we have a load consuming every watts the generator can provide.
Would it be wrong to state that the generator would need to disconnect it's output from the load and wait n AC cycles to... |
H: How can I unlock two relays at the same time with one push button?
I am making a circuit to control the opening and closing of a small gate with two push buttons and two limit switches. The gate open and close functionality already works, but I want to add a general emergency stop button. I can't find a way to put ... |
H: Voltage behaviour in battery-powered vehicle when motors regenerate
I am wondering how the voltage in a battery powered vehicle will behave in case its BLDC motors are acting as generators (i.e. while decelerating). In a system powered with a DC/DC converter for example, the voltage would rise by the amplitude of t... |
H: How is a mains-connected medical device made safe against electrocuting me?
I am in physical therapy now. Some of the devices are connected to wall power, and used for muscle electrostimulation. The patient information states that no single malfunction can connect me to 230V, and any malfunction that would allow a ... |
H: Use of Zener diode
I was constructing the UC3843 on PSIM from scratch. The circuit diagram and the application note state that if the input voltage is greater than 34 V, the Zener diode does not allow the circuit to run.
This is how it seems in the block diagram of the UC3843:
However, in my PSIM, the circuit stil... |
H: Is there a specific definition for the tolerance value of a resistor?
Is there any authoritative definition for what the tolerance value of a resistor actually specifies, or is it just a de-facto common understanding, or are the details left up to individual manufacturers?
To put it differently, If I very precisely... |
H: Output current of full-bridge rectifier with LC filter
I am learning about the properties of a full-bridge rectifier (with LC filter).
Now, I want to find the output current of the 124 Ω resistive load.
(Vpeak of the AC voltage source is 311 V with no DC or phase offset)
My idea is to first find the impedance of t... |
H: P-channel MOSFET saturation condition: math contradiction
I am using a P-channel MOSFET with Vt = -0.4 and Vgs > -0.4 => Vs = 0 Vg > 0 always so it's not supposed to conduct.
Vdg > -Vt = +0.4 for the linear state.
At V2 = 0.2 our plot is linear state, but mathemetically I get the opposite: Vdg = 0.2-1.8 > -(-0.4) =... |
H: Transistors falsely latch with EMI
I have a very basic NPN - PNP latching circuit:
[Sorry for the upside down image]
The latch initially is off, and when the op_amp_Signal_and_latch turns on, the transistors should latch and there should be output to SignalOut+ which drives other transistors.
I just made the latch... |
H: Can I convert a 36 volt battery to a 48 volt battery or how do I extend a 48 volt 10 amp hours to 48 volt 20 amp hours?
How do I convert a 48 volt 10 amp hours to 48 volt 20 amp hours battery? Can I convert a 36 volt battery to a 48 volt battery?
AI: The only way to convert a 48 V 10 AH battery to a 48 V 20 AH batt... |
H: Problem with mini sliding gate
I am learning about relays and to practice what I have learned I have decided to make a small electric gate using the following method. I am making a circuit to control the opening and closing of the gate with three push buttons and two limit switches. Pushbutton S1 opens the gate, S2... |
H: I think that these gate resistors are 2.2 kΩ, isn't that rather high?
From this video, Pace MBT 250 rework station with a Gordak handpiece and Arduino by Fodor Tibor, @ 17:27, this "close up" photo is shown of the board:
Note the seven blue metal film resistors that go between the digital output pins to the gates ... |
H: Maximum Ambient temperature
In this IC, on page 35, the maximum operating temperature is given as 70degC or 85degC.
Is the datasheet maximum temperature value of 85C applicable to the surrounding medium? I ask because air will not be in contact with this component; it will be another material.
AI: The data sheet is... |
H: Using a PNP transistor with a NPN transistor not working as intended
I have an element represented by the two resistors in between NODE1 and NODE2.
I want to be able to open and close the circuit before and after the element, just like having two switches before and after it.
At the moment I have this schematic. (T... |
H: 10 MΩ resistor needed on op-amp input for correct operation
Circuit:
The 3 kΩ in series with the switch in the circuit represents a metal probe that gets connected to ground when water is present (switch open = no water; switch closed = water).
Due to the metal probe starting to corrode I need to use a bi-polar sq... |
H: Help with PNP transistor schematic
I would like to build a FM radio reciever with PNP germanium transistors but I can not find a simple yet efiicient schematic for this. Does anyone know of a schematic I can use?
I have found one schematic that I've built, but it doesn't work. Maybe it's because I have used other ... |
H: Can I use a buck converter and a 12 V adaptor to create a 5 V and a 12 V circuit?
I have a microcontroller that is powered by 5 V and some solenoids that need 12 V. At the moment I power the solenoids using a 12 V adapter and switch them on and off through MOSFETs which are in turn switched on and off by the microc... |
H: Quiescent current in battery circuit
In this circuit I'm using an MCP73832 for battery charging and an AP2210 LDO. The mosfet is a DMP3099L. With the USB disconnected, VBAT set to 4.2V and the MCU (STM32F030F4P6) in standby mode (drawing < 10uA), the total current graph looks like this:
The average current is aro... |
H: Op amp stability consideration
I would like to have your opinion on this circuit :
The source voltage V12 is a feedback of an other loop hidden. So the operating point of the system is changing.
When the 47 Ohm resistor R1 is connected to the NPN, the system seems to be stable according to LTspice and it makes sen... |
H: Why does the MOSFET drain potential show this strong turn-off overshoot? How to fix it?
I am trying to build a PV charger (PWM), which I guess is kind of a buck converter. Below is a first LTSpice simulation. V1 are the PV modules, V3 is the battery. V2 is the microcontroller's supply voltage. L1 is my estimate of ... |
H: Which transistor is the best for switching on/off a LED with an ESP32?
I have bought a transistor set a while ago and I never used it so I thought I would give it a shot to make a simple circuit. I'm very new to electronics and the math behind it so I'm sorry if it's a really simple question. These are the transist... |
H: How to design a circuit with dual power source?
I have a LED that can be powered and controlled by a MCU (ATmega328) and would like it to be able to take power from battery.
The battery (5 V) can be plugged or unplugged when needed, it's the secondary power source.
Requirements:
When battery available led should ... |
H: How does the TI CD14538BM96 behave in response to long input pulses?
This is related to my earlier question on driving dual coil latching relays from a single logic signal.
This question is on how whether the TI CD14538BM96 monostable multivibrator can be used to convert an input signal with very long pulse duratio... |
H: Is it OK to route a signal trace under an STM32?
Is it okay to route an SWCLK signal (for programming the STM32 microcontroller) under the STM32?
I will use it only to program it whenever I need it; it is not something that is always active.
Please see the attached figure:
Look at the yellow trace under U1 (STM32G... |
H: Multiple 10-bit, 500 Hz PWM outputs from a shift register (e.g. 74HC595) with a single 16-bit input (e.g. from an ATmega328P)
I would like to produce as many 10-bit PWM outputs at 500 Hz or less as possible using a single pin of a microcontroller, in this case an Arduino Uno, and a SIPO shift register.
I found this... |
H: Which component for disconnecting RS485 data signal?
I have a situation where I'd like to be able to connect/disconnect the RS485 signal path between two PCB-mounted XLR connectors with one 3V3 output from an ESP8266.
What's the best way to achieve this? My instinct is some kind of small SPDT relay, but a lot of th... |
H: Delay.h on ATtiny45 vs. ATtiny461 in Microchip Studio
I noticed that the Delay.h wasn't working well in a project when used with an ATtiny45, so I've made a small piece of code to test where I went wrong with my coding. I've just made a blinky-LED program on PB3 which goes on for 200 ms and off for 500 ms.
#define ... |
H: Getting started with STM Nucleo boards. Mapping from processor pins to board functionality (like LEDs)
Please tell me if there is a more appropriate group!
I'm just starting with STM developmeent using STM32CubeIDE. I have a background in programming (C#/C++/C) on the desktop and some minor experience in electroni... |
H: Turning on a transistor if one voltage is higher than another
I would like transistor Q1 to turn on if V1 > V2 with a maximum tolerance of about 0.5 V.
I want to feed the entire circuit with 5 V. Which operational amplifier do you recommend?
And how should the circuit be wired?
simulate this circuit – Schematic cr... |
H: understanding the slew rate step of implementing gm/id method question
I am trying to follow method descibed in the article bellow.
we need GBW=100MHz SLEW_Rate=50 V/us Load=1pF
In step "A" they try to find Width of NMOS we have the plots
Gm/Id Vs Id/W, ft vs Gm/Id, gm /gds vs gm/Id for L = 180 nm
Gm/Id=GBW/SR=12.... |
H: NOR gate turned into a LED killer
I'm trying to build a simple NOR gate, but I've accidentaly made it so that whenever all the switches are off the LED is on, but when I close one of the switches, the LED simply dies.
This is the circuit I have:
simulate this circuit – Schematic created using CircuitLab
I figured ... |
H: Get Motor RPMs from Resolver Signal
everyone.
I have a servo motor that outputs a resolver signal (sine, cosine, and reference). Each of the three signals is a differential pair (+A/-A, +B/-B, etc.). And the three signals are encoded using an 8 kHz carrier signal. Below is a plot that I made from an oscilloscope... |
H: Using resistor to drop voltage in circuit with changing current
I have no problem calculating and understanding how to drop voltage using resistor for circuits with purely resistive loads - for example look at much current will an LED draw, subtract source and LED voltage and just use Ohms law to find out the right... |
H: How to wire a 6-pin relay?
I have the relay described in this datasheet. I have the z-type. It has 6 pins on the bottom.
I want to control this relay with an Arduino device and all it has to do is work like a switch.
simulate this circuit – Schematic created using CircuitLab
How do I wire up my relay to function l... |
H: TVS diode vs capacitor
I've gone through this link which is a similar question.
In some places, capacitors are also used for ESD purposes.
In some places, along with capacitors, TVS diodes (or ESD diodes, not sure which term is correct) are used.
Can someone tell me where TVS diodes should be used and where capacit... |
H: SPI interrupt signal
My question is based on this question over here.
I just want to clarify what is the purpose of the SPI interrupt signal. Isn't the 4 SPI clock and data lines, & chip select sufficient for the SPI interface?
Also, is the SPI interrupt signal an input or output signal?
I'm using this module. Want... |
H: Long Term Drift of IC
I wanted to calculate Long Term Drift of output voltage of an IC and in datasheet the value is given as 60 ppm/√kHr. I dont know what exactly this means as there is square root of kHr. Can anyone pls help me for 3000 hours what would be the long term drift of this IC? attached is the graph fro... |
H: Watt to amp-hours of AC device
Please help me understand the calculation in this table. The writer has a 12V batery connected to a 12V/110V inverter connected to standard house-hold AC appliances.
The calculation for the 1000W induction stovetop is:
1000W/12/0.85=98. 98*0.75h=73.5Ah (where 0.85 is 15% power convers... |
H: How can I recreate a circuit like the WS2812 addressable RGB LEDs without the actual strip?
I've tried googling, youtube, even chatgpt but I'm not quite finding what I need.
Can you point me in the right direction for how to create a custom circuit similar to an addressable RGB LED, where I can connect multiple out... |
H: First time designing an SR latch; I'm using it to control the enable pin on my eFuse IC. Just want to know if I'm overlooking anything
I just finished designing my rectifier module that has a built-in voltage monitor IC and an eFuse IC.
Its purpose is to convert the 3-phase AC output from my wind turbine and use it... |
H: SMD component identification: ADI "8 8A"
I'm having trouble identifying this ADI part on this board I'm working on. I'm assuming it's ADI from the logo on the left, and the text on the right just says "8 8A". I've had no luck finding this IC from the ADI package marking database and general searching. Would anyone ... |
H: Weired result of Ltspice Zin measurement, Phase shift of -104°
I am trying to measure the input impedance of this amplifier to design a matching network for it. But the input impedance I get has a phase of -104° at the frequency of interest. I thought that Phase could only go from -90° to 90° how is -104° possible ... |
H: Is the voltage / power running through an exposed Bluetooth keyboard enough to be hazardous?
Unusual question and potentially not the right forum for it. Apologies in advance.
In short, I have cracked the shell off a Bluetooth keyboard and modified it (read: Jerry rigged it) to be as light as humanly possible while... |
H: How do I properly route my signal to this BNC connector on my PCB?
I am looking to use several of these Amphenol BNC connectors on my PCB.
When I look at the datasheet, my instinct tells me that I should route my signal to pin 1 and then ground the rest.
Here is the PCB symbol and the datasheet. Neither have good ... |
H: LM317 output too low
I am trying to figure out an issue that I have with LM317 regulator.
It is producing ~ 1.7V at VOUT instead of desired 5V.
I've used this design in several other PCBs with no issues.
The schematic is following:
The layout from both sides:
Couple of observations:
Vin measures stable 12V at f... |
H: Module with LM7815 and LM7915 voltage regulators has 3 pins for input and output - why?
Why does this +-15 V voltage regulator have 3 pins at the input and at the output?
AI: It has two voltage regulators on board, and can handle two input voltages, positive and negative plus common ground, and has two outputs, one... |
H: Are inductors used in series with power rails/power supplies for unregulated noise/ripple filtering?
I am wondering if I should use a inductor in series of my power supply rail at the input of my PCB to reduce potential noise coming from the cables connected to my PCB like this:
simulate this circuit – Schematic c... |
H: GP2Y0A21YK0F Sharp IR sensor not counting below a certain distance threshold
I'm building a self-navigating robot that uses IR sensor (GP2Y0A21YK0F model) with Arduino to navigate through a terrain, however during testing phase when I put my hand closer than 7cm it bugs and doesn't detect if anything can be closer ... |
H: How does balancing via resistors work? Why isn't it needed inside of batteries?
I am building a hobby project - a sort of supercapacitor powerbank, where I basically connected twelve 500F 2.7V supercapacitors in series. Despite these capacitors being from same manufacturer and same batch, I instantly hit the disbal... |
H: Multichannel voltage measurement system
I have to make a simple system that measures the output voltages from a power supply. In total there are 8 voltages from 3V to 32 V to measure. The system is based on an STM32 microcontroller. The sampling frequency will give very low, say around 500Hz.
The analog input (the ... |
H: RC frequency for PWM signal
I have recently read this project and would like to ask for some clarification regarding this statement/calculation:
"The values shown work well an operating frequency of 1.95KHz or 13 bit operation with 8192 steps (2 to the power 13 = 8192)."
It filters the PWM signal with R and C, but ... |
H: Approach for programmable power supply that provide positive and negative voltage
I want to design power supply that output sweep from positive to negative voltage for dc motor parameter estimation. About +-12V 5A.
Are there any approach for this kind of application.
I have some concern as following.
I try to avoi... |
H: How to implement a 2-layer PCB antenna on a 4 or 6 layer stack-up?
I am new to antenna designs. Lots of design guides mentions that no ground is required on the second layer (antenna on the TOP layer, IFA or MIFA for example.)
I'm wondering to how to implement a 2-layer PCB antenna (MIFA) design for example on a 4 ... |
H: Are TO-220 and TO-247 MOSFET heatsinks compatible?
Are TO-220 and TO-247 MOSFET heatsinks compatible?
AI: Not in general, but it is possible.
While the mount-holes are approximately the same size, the TO-247 is larger than the TO-220.
The problems you will run into:
A heatsink made for TO-247 when used on a TO-220 ... |
H: Single-supply non-inverting op-amp for summing DC voltages at unity gain
Is it possible to use this single supply, non-inverting, summing op-amp configuration to sum multiple arbitrary DC voltages at unity gain?
I've used the inverting summing op-amp config on bipolar power supplies to sum AC and DC input voltages ... |
H: What is the difference between PACK- and BAT-?
I have a doubt about what is the difference between BAT- and PACK- in this battery management system available in a github project:
As I read in the datasheet of the BQ76920, the N-Channel FETs are for cell balancing and protection, and the R10 is for sensing overcurr... |
H: EMF Sensors - Tri-axial Inductors vs Tri-axial Magnetometers
I took apart a bunch of EMF sensors (such as this one) and found that almost all of them instead of having a magnetometer inside, have usually three inductors. In the case I just shared, it has 3 33mH inductors, each orthogonal to each other. Here's a pic... |
H: What power supply should I use for this 12 V peristaltic pump?
I have a project I am doing where I have to control three simple peristaltic pumps with an Arduino. Originally I started with cheap $13 6 V pumps powered with 9 V batteries which only worked for a day, then wouldn't even work when connected directly to ... |
H: SMD inductor soldering tab termination
I'm not very expert with SMD components. When I was looking for an inductor I found this component:
The termination style is solder tab. How can this be an SMD inductor when the leads are perpendicular instead of being flat?
How are the leads soldered to the surface and not ... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.