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H: What is the real and apparent power of these steel cutters?
The US market model of this steel cutter is 120 VAC, 13.0 Amp.
The NZ market model is 230 VAC, 1,100 W.
I am trying to wrap my head around whether 1,100 W is the real power and so whether the apparent power is 120×13 = 1,560 VA. That comes to the power fac... |
H: VERILOG: why Xilinx AXI Slave declares all output signal as a wires and not reg?
I am reading the code for an AXI Slave provided by Xilinx (here below).
I am wondering why they declare all outputs as wire and then assign them to an internal register that is modified within always blocks (see for example the S_AXI_R... |
H: Are vehicle electrical components powered from the negative side?
still trying to get my head around electron flow as opposed to conventional current regarding automotive electrical circuits. There seems to be a ton of conflicting information/advice out there so I'm hoping to seek some clarity.
Basically I'm just w... |
H: Problems casting a uint8_t array to a struct
I'm having problems casting an array of uint8_t to a struct in C using a Silicon Labs MCU (EFM32GG11B120F2048GQ64). The byte array is the received data from a UART, and I want to cast it to a struct representing the message structure.
When casting the array to the struc... |
H: ATSAMD11C SERCOM I2C Pin Assignment
I am planning on using the ATSAMD11C14 (SOIC14 package) for a project that requires USB, 2 I2C busses, and some GPIO.
The device has two SERCOMs, each has 4 pins assigned to it. When used in 2 wire I2C mode, only two pins are required for communications. Does this mean that the o... |
H: LM2576 unload state
I've seen something weird with the LM2576 diode waveform when I leave it without load and with the load. Here is the diode waveform when I put a 100ohm resistor as LM2576's load.
It seems the circuit and diode works fine. However, By removing the load I see this diode waveform:
I need to know... |
H: Correct way of estimating delays in FPGAs
What is the correct way of estimating delays when doing operations in Verilog?
For example:
reg [31:0] a, b;
...
wire [31:0] res;
assing res = a + b;
The above + operator could lead to very different delays depending on if it is synthesized to a ripple-carry adder, a carry... |
H: Designation "2-" in a technical drawing of a component
What does the encircled "2-" designate in the technical drawing below? Is it some standardized/common designation of something? "R" stands for the radius, and the numbers refers to the values in mm.
The picture is an excerpt from the 6th page of this document.... |
H: Driving parallel channels with 1 PWM signal
I am currently developing a protoboard for an LED driver having PWM control for dimming using a microcontroller. I plan to drive a number of parallel channels of LEDs ('n' number of RGB channels) and have it opto-isolated as well.
My question is, is it okay to drive these... |
H: Current source with MOSFET
In the circuits below, what does the 100R resistor do?
In my understanding the 1K along with the 200 pF create an integrator topology to provide some stability but how about the 100R that feeds the gate of the MOSFET?
What does it do?
Wouldn't that delay the on/off time of the MOSFET's ch... |
H: synchronous buck simulation
I got confusing result from hspice simulation but I can't get it.
the voltage at "N1"should be 4V when W1 on,and be 0 when W0 on.
but result is always 0 and pulse of negative voltage.
below is the concept pic ,code,and waveform
AI: A synchronous buck converter can be easily simulated wit... |
H: Is a current limiting resistor needed for dual opamp supply pins?
Consider the TL072 dual op amp that is supplied with +/- 12V. The datasheet says that the supply current for (each) amplifier is typically 1.4 mA, with maximum of 2.5 mA. If both amplifiers are operating, should the current be limited to 2.5 mA on ea... |
H: Open ended LM2937-5 outputs 12V
The LDO, LM2937-5, with 12V input voltage and nothing connected to the output terminal, outputs 12 V (measuring using voltmeter). As soon as I connected 100 uF capacitor, it shows 5V.
Datasheet clearly states that output capacitor is required, but it does not say about overvoltage, r... |
H: Do I need RTC while I'm using NTP?
We know computer and another device like microcontroller is not accurate in ticking clock comparing to wall clock that using cesium atom.
I heard RTC module is purpose to making accurate the ticking.
But microcontroller that I used is Espressif family which they have built-in Wi-F... |
H: What capacitor is this (part number)? Looking for the datasheet
I'm trying to find the datasheet for this 1.0F & 5.5V capacitor. Some identifying labels on it are "GC", "Japan", and "822". I haven't had luck in my googling, so does anyone know what part number this is?
AI: It seems consistent with Panasonic's dis... |
H: Adjusting the drive strength of level-sensitive interrupt signal
In my current environment, the interrupt source comes from an FPGA on a daughter board and connects to a GPIO pin on an EVB:
daughter board (interrupt output signal from SD controller)--> EVB(GPIO pin with interrupt enabled).
The GPIO interrupt polari... |
H: Would appreciate some tips on designing simple OpAmp circuit
I've recently posted this question regarding input impedance when working with DC signal on HCPL-7840 Isolation Amplifier. The answers were very clarifying and helpful, but I've come to realize I need more specific help.
Just a disclaimer: I decided to us... |
H: Splitting of a differential signal
Can the Ethernet Tx and Rx signals (Using all 4 pairs; RGMII interface) be split into 2 so as to connect to 2 RJ-45 connectors, but only 1 will be used at a time. In general, can we split any differential signals for 2 outputs?
Edit:
Added a picture for better understanding of my ... |
H: Linear power supply - overload protection circuit
Summary and context:
Several years ago I bought a linear power supply from Pyramid, model PS-3KX.
I would like to understand in detail how the overload protection really works, as said by Pyramid manufacturer (red box in the Specification part).
It seems the PS-3KX... |
H: Why in this circuit the collector of Q2 is receiving negative voltage?
According to when we say the collector in a transistor is reverse bias and the base and emitter are forward bias, why in this circuit (since Q3 or Q4 are NPN, so the emitter should be connected to negative voltage) the collector of Q2 is receivi... |
H: Which part of this transistor model op amp represents pin 5?
In this op amp oscillator pin 5 is connected to an RC circuit:
I have a transistor model of that op amp and I want to connect an RC circuit to it like the above circuit:
Since pin 4 and 8 represents the voltage source of that ideal op amp, I am not sure... |
H: RS-485 Network Topology with Backbone and Daisy-Chain Stubs
I am designing a RS-485 network and would like to know whether the configuration below would work. The transceiver I am using is the Maxim MAX485, with the master ad slaves hardwired to always transmit/receive respectively. My target bitrate is 1 MHz.
The... |
H: Matlab: spectrum analyzer does not display the output from "Sample and hold block"
I try to use the Sample and Hold function, to show its output on the spectrum analyzer. But it gives me this error "Spectrum cannot be displayed for continuous or infinite sample times", while I dont have infinite, not continuous sam... |
H: How to deal with one clock input at the IC when most crystals and oscillators have two pins?
I am having trouble in figuring out how to deal with an IC that only has a single input for the sleep clock. Does one pin of the clock go into the IC and the other to ground, or does configuration vary from device to device... |
H: I designing a pulse generation circuit using capacitor and resistor but my output is not coming as expected
I am designing a pulse circuit which I will be feeding to a comparator. I am using a combination of resistor capacitor and diode for generating positive edge triggered pulse as shown in the below figure (enci... |
H: BJT: definition of "edge of saturation"
The book Sedra/Smith (Microelectronic circuits) tells in chapter 5 the following:
My question: I found no statement on why the EOS is defined by the point where vc < (vb - 0.4V).
Seems like other books just define saturation at where vc < vb, and I even saw vc < (vb-0.7V) so... |
H: Why is high open loop gain needed for an Op-Amps virtual ground?
In books, I often see that they state that the op-amp has a virtual ground property when it has a high open-loop gain and in a negative feedback configuration.
First Question: The negative feedback part makes sense to me, but why is it necessary to ha... |
H: Why does MOSFET N back to back switch work?
Please consider an exemplary back-to-back MOSFET N driver IC (drew the body diodes of M1 and M2 for clarity):
I understand how is it possible to turn off the M1/M2 transistors from the gate voltage point of view (since its higher than VIN voltage due to the internal char... |
H: What can this CAN bus like protocol be?
I am currently probing what seems to me the CAN bus twisted pair of my car. But the signals are not what I expect. One of the pair is like a typical CAN HI signal, however the idle state is a 0V and a logical high is 5V. The CAN LO signal on the other hand is idle at 5V and a... |
H: Power supply noise reduction
I am new to electrical Engineering and would like to know wich noise reduction filter ist better for use in audio equipment.
Some decalcifications:
VBUS --> 5V from usb-port
GND --> Ground from usb-port
INT_GROUND --> Internal ground I use for all my components (I just like to separate ... |
H: Is it better if each integrated circuit has a dedicated voltage regulator?
I have a circuit consisting of an ESP32 microcontroller and some integrated circuits. Is it better if each integrated circuit has its own voltage regulator?
Example:
Full circuit after modification :
AI: The only reason to do what you are ... |
H: Multiple voltage sources connected to Attiny85
I have a circuit with a Attiny85 micro controller that is powered by a solar cell and a capacitor (10F 3V8). When I want to change the code on the micro controller I have to attache a USB programmer that operates (and provides) 5V. Since the circuit will be soldered I ... |
H: Snubber circuit for electromagnet
I have run into the same problem described here and here, when I added diode to electromagnet. Basically, the magnet still holds with about 20kg force several minutes after removing power. The mechanical solution of leaving air gap or adding a "peel-off" spring is not plausible due... |
H: Is this avalanche rugged MOSFET suitable for linear operation?
I would like to create an active load which draws current(4 to 6A) from a 12V battery. Unfortunately, the shipping costs and delivery times have prevented me from buying Linear FETs directly from well known manufacturers. Instead, I have found this inte... |
H: Understanding Spec sheet of IC
I'm having trouble understanding the spec sheet of this shift register. What I want to do is to connect a (generic red one, I don't have any specs) LED which will approximately use 15-35 mA to the IC.
I am currently doing this as seen in the first scheme. The output pins of the IC (\$... |
H: Battery capacity and parallel vs. series battery connections
Say you have 4 200 Ah 12 V batteries connected in parallel, this as I’ve come to learn increases the amp-hour value and not the voltage, and say you have another system same as that but connected is series this time, this increases the voltage and not the... |
H: I can't figure out what this circuit does
I'm an electrical engineering student.
The picture below shows a circuit that I found in some old notes but I cannot figure it out.
I have been at it for the last 2 days but to no avail.
Some things that are known for this circuit are:
Beta is close to infinity.
All transi... |
H: VoltSecond equations for equivalent buck-boost of flyback
Here is the equivalent buck-boost of flyback converter:
I proved the Volt-Second in a switch-on mode that agrees with the book result (n=22.86.)
In switch-off mode (regarding the above table):
$$t_{off}=(1-D)/f=2.94us$$
$$V_{off}=V_{diode}+V_{OR}=n*V_{D}+n... |
H: Coding and SNR gain
How does coding reduce the amount of SNR required to detect data for a certain modulation and at a certain bit error rate and does that imply that coding reduces noise power?
AI: How does coding reduce the amount of SNR required to detect data for a certain modulation and at a certain bit error... |
H: Negative to chassis or separate wire?
In automotive applications typically battery negative is connected to the chassis, right. This makes the chassis be at the same potential as battery negative, but when completing a circuit, ultimately the charge needs to return back to the battery. Bearing in mind that the chas... |
H: How will I implement this function with decoder and multiplexer?
Inputs Output
A B F
0 0 C.D
0 1 C
1 0 C+D
1 1 C XOR D
According to the logic input-output relations
a-) Find the simple form of the F logic function.
b-) Implement the F logic function with the decoder.
c... |
H: Relation between number of RC networks and phase shift in RC phase shift oscillator
The generalized expression for the frequency of oscillations produced by a RC phase-shift oscillator is given by the formula below
$$f=\frac1{2\pi RC\sqrt{2N}}.$$
Here \$N\$ is the number of RC stages.
The link for the website I ha... |
H: How can a DMM measure open circuit voltage?
This question has bugged me for some time now. How can a DMM measure open circuit voltage?
I have a general grasp of how ADCs work. How is an open circuit voltage measured when that should produce a voltage drop because of the battery's internal resistance?
AI: Let's hav... |
H: LLC resonant capacitor RMS voltage and output capacitor ESR calculation
I have a question about the TI LLC document.
On page 25, Select the Resonant Capacitor, I don't understand why it can use this formula to calculate the RMS value. Could someone tell me how to get this formula?
On Page 27, I don't understand wh... |
H: Op-Amp with current source input
In this op-amp circuit, the output is defined as \$v_o = - i_sR\$.
Question 1
I am slightly confused about how the current flows in this circuit. By the principle of virtual ground, the inverting input is at 0V. The output is at some negative voltage. Hence the current flows from t... |
H: How do constant current constant voltage devices work?
First of all can a device that is constant current also be at the same time constant voltage? In my head I just could not grasp how this device can work.
Individually I understand how it works, constant current supplies adjust the voltage to sustain the target ... |
H: Making a voltage range filter (or a voltage bandpass filter)
I have been trying to hack together a voltage range filter that will pass voltage to a load only when the input voltage is between 1-2V. My input source can range from 0-3V. (I don't want to scale the voltage with a divider, by the way. I want to filter o... |
H: Electric stove place thermostat so far from heater
I buy electric stove and found that thermostat placement doesn’t make any sense.
The thermostat used seem like one in iron, in that case, the iron heater connected directly to thermostat via ceramic ring.
In this electric stove seem like it regulate air temperatur... |
H: How can failure of Class Y capacitors lead to electric shock?
This article mentions "Due to the fact that equipment cases are usually grounded, Y caps require higher safety to avoid risks of electrical shocks to users"
How can an equipment with chassis grounded cause electric shock?
Even if Y capacitor shorts t... |
H: Ethernet Switch and QoS Support
I'm going through the Ethernet Switch IC - Link
In the first page, under highlights section, it is mentioned as switch is QoS support.
When I tried to research on what QoS means on this Link, I found the below image:
But as I recall, Ethernet protocol was a baseband interface protoc... |
H: Why are differential mode chokes (inductors) not generally coupled?
I understand there are both coupled and un-coupled versions of differential mode chokes as shown below.
Which one is better? I see most of the designs having un-coupled version. What is the reason?
Coupled differential mode inductors:
Un-Coupled d... |
H: What is the core material being used in CMC (Common mode choke) and DMC (Differential mode choke)?
The core symbol in below diagram indicates that it is an iron core material but Iam not sure whether it is correct. I see the same representation in many other circuit schematics as well.
Below ref says
"To prevent s... |
H: Can I power a router that requires 12V-DC via a 5,5mm input by using a powerbank that can output 12V DC over USB
I have a powerbank that can output 5V-3A/9V-2A/12V-1,5A over USB. The router I would like to power came with a 12V-1A adapter and uses less than 12W. If I were to buy a USB to 5,5mm adapter cable, would ... |
H: Low Side Parallel MOSFET Drive
I'm doing a 12V to 230V push pull inverter design & need to drive it via two MOSFETs for each transformer tapping. Mosfets feeds by an optocoupler PC817. The frequency is 50Hz coming from a PIC microcontroller. Going to do as below.
Am I driving it correctly? Any improvements?
Thanks... |
H: What are the d and q axes for induction machine?
What are the d and q axes for an induction machine (physical meaning)? I understand them for a synchronous machine but how are they defined for an IM?
AI: The same as synchronous machine. Physically they are not rotated in relation to the stator with rotor angle, but... |
H: Why is my LED flickering when it is connected to a variable resistor, and it's resistance is at the minimum value
I am doing a simple breadboard circuit, with an LED, 3.3V power supply (a microcontroller connected to the PC will be the voltage source), a potentiometer, and a Voltmeter connected across the LED.
This... |
H: Source Transformation
Ok, I have modified my question again about the same circuit seen below:
I have to simplify the circuit using source transformation and then find the current ix.
I have attached my attempted solutions but I do not get the correct answer of ix = 0.9A ( I am getting 4.3 amps now).
What I sup... |
H: USB 3.0 Length matching in PCB Layout
I'm doing PCB layout for a USB 3.0 connection and I'm curious about if there's a length match requirement between the unidirectional super speed pairs and the bidirectional high speed pair. This isn't for a specific USB 3.0 driver or receiver, but what is considered good pract... |
H: What is a "reactor"?
Watching some of the restoration videos of old tube/valve devices by Mr. Carlson's Lab, I've heard him describe a circuit element called a "reactor" on several occasions - for instance here, where the circuit includes a "saturable reactor". So far, I have not come across a component of that nam... |
H: Necessary voltage to charge NiMH using Solar Panel
I'm trying to understand which voltage I need to charge my NiMH batteries so I can purchase the components to do this.
Actually I have 2x AA Ni-MH 1.2 V 1900 mAh and 4x Solar Panel 2 V 220 mA (0.44 W).
I read Solar Cell - Preventing overcharge of an NiMH battery an... |
H: What is the RGB value of Edison Light Bulbs?
I've been doing a little electrical engineering (outside of my lane a bit). I'm trying to get the RGB values for Edison light bulbs. Can anyone provide me with those?
AI: I used Firefox Web Developer Eyedropper to grab the RGB from a photo of an Edison Light Bulb.
#F... |
H: Is there a difference between specialized audio amplifier and general op-amp silicon?
I've been doing some research into creating a DIY audio amplifier from line-level inputs to speaker level power. I found a guide centered around the LM386 Low Voltage Audio Power Amplifier on YouTube here.
I have a fairly large c... |
H: How are PWM IC's able to provide so many features in small footprints ?
If you look at the general pwm IC's for standard topologies (buck, boost etch) , they have tons of protection features such UVLO, overvoltage, cycle-cycle protection and overcurrent protection.
They are able to provide all these features in a ... |
H: What should be the voltage rating of bootstrap capacitor?
BST_1P is the bootstrap capacitor connection pin for high-side gate driver of TAS6422.
In the datasheet it is suggested that, this capacitor should have minimum rated voltage of 16 V.
What is the factor deciding this rated voltage.
Consider the maximum supp... |
H: Operating a fan on UPS
A short, useless intro to the question, feel free to skip it:
I had a power outage in my home yesterday. Power outages aren't what they used to be - Back in the day, it rendered me completely unable to do anything, but nowadays I have my laptop, which is still connected to the internet via my... |
H: Why do shorted PSU probes stick together just a bit, even on very low power?
I'm using a standard bench power supply set to 3.6V and 0.5A. I also tried 0.05A.
I then bring the positive and negative terminals together in a short circuit, and I noticed there is a noticable sticking effect between them. I have to use ... |
H: Why doesn't my bench PSU read current on a breadboard?
I've recently purchased a cheap eBay DPS3012 DC-DC converter supply. I intend to use it on breadboard projects.
The "problem" is that the meter reads a 5V output, with no current being drawn and therefore no power. However, the LEDs and ICs are working properly... |
H: Contact pressure vs contact area
I'm learning to weld. I've realised my earth clamp is limited. The spring is weak and its contact area is small as it's tooth shaped.
Researching better clamps, I see clamps which have threaded bolts to clamp the jaws against the workpiece tightly. It is my understanding that unless... |
H: The 555 regulator that won't regulate
I made a 170V step up converter using a 555 timer for my Nixi project.
At first I tried to run it using 5v but could not reach a 170v output, so I opted for a 12V supply and put in an LM7809 regulator. I put a heatsink on it although it probably does not need one.
I was able ... |
H: Un-masked Copper Boundary across RF section
I have seen so many PCB which has an un-masked (without solder mask), copper boundary across RF sections. The boundary has via-stitching and there are also few openings in the boundary. Can someone explain their purpose? Please have a look at the picture below:
AI: You me... |
H: Clock domain cross and metastablilty problem
I understand the problem of metastability and understand that we can't get a stable value in a bounded time so we need unbonded time but it is not practical,
so we put another flip flop with no logic to let a complete clock period be available to the metastable state to... |
H: Calculating the oscillator frequency
I am trying to calculate the frequency of the internal oscillator, in order to go through the design procedure listed in the datasheet. The problem is that it gives me answers that contradict the 100kHz max f specification. Here is my calculation with the example values in the s... |
H: Having issues with using simultaneous timers [STM32]
In my nucleo L432KC, I have set Timer 1 for PWM generation, Timer 15 as a timer based interrupt and Timer 2 as PWM input mode. Timer 1 and Timer 15 works well until a point. My clock frequency is 2MHz. For example, I wanted a 50 kHz update event, so I set Timer 1... |
H: Pager system charging pin and socket
Does anyone know what these pins are called? This is a pager from paging system used in certain restaurants. I'd like to know what it's called as I want to use it in my device's design. I need to know what socket is used with it, but that would be easier to find if I can find th... |
H: ESD diode selection based on VCC of the IC
I have a question about TVS diode selection.
This kind of question is already discussed in previous questions.
ESD Diode - GPIO Microcontroller
Selecting a TVS for ESD protection
For protecting vcc line of a controller with nominal VCC = 5V, 5%, maximum vcc = 6V.
We normal... |
H: Increase Boost Converter Current
I'm building a portable charger for my phone using a large 2.7v supercapacitor, which uses a very simple boost converter to create 5v. I am not concerned about input current, however, when a load (my phone) is connected, the voltage falls to 4.53v, regardless of any changes I make t... |
H: Ring around wire on diagram
If this is a repeated question, please let me know. I'm a hobbyist electronics person, and ran across symbols on a diagram I didn't recognize. I've attached the image below:
What I'm trying to figure out is what the different rings around the wires mean. For example, Earphone Pilot h... |
H: Is rated current supposed to vary based on voltage?
Recently I have been reading a lot of datasheets and noticed that many manufacturers specify a current rating for their products (especially connectors) without specifying at what voltage the current rating applies (except for a max voltage). This seems super cou... |
H: Wire to board connector for Test Jig
What's the best way to quickly connect/disconnect ~22 AWG wires to a test jig pcb? I would like to use a spring loaded connector that can easily release the wire after I'm done testing. Currently have these
However they're expensive and don't hold the wire the best. I would lik... |
H: Is it possible to make a lightbulb light up by wetting your hands?
I was recently watching an Electroboom video on free energy devices, but my question is not about any of that stuff. Here's the video. At about 5:50 he claims and seemingly shows that he can light up a light bulb using his muscles and by wetting hi... |
H: Nichrome wire temprature
I have recently been working on a project in which a material, whose ignition temperature is 500 °C, is to be ignited.
So, what type of nichrome wire would be suitable for me, if I am using a 5 V power supply capable of 5-10 A and length of wire is about 1 cm?
AI: Normally I'd do a technic... |
H: Are Cal Kit (SOLT) definitions unique by serial number?
I have an E5071B Network Analyzer and 85033E cal kit.
One of the standards is broken now and needs to be replaced. This is the Male OPEN standard (Part number 85033-60018).
Question:
Will the definition files (that come on the floppy disk, and are now instal... |
H: Why does these capacitances have no effect on the output of this amplifier?
Below shows a piezoelectric sensor connected to a charge amplifier:
The text claims that the output voltage Uout is to a good approximation only charge q which is going to be measured divided by the feedback capacitor value Cf.
The text th... |
H: advantages of PC-relative addressing
I have read somewhere:
"The advantage of using
relative mode over direct mode is that relative addressing is a code which is position-independent, i.e. it can
be loaded anywhere in memory without the need to adjust any addresses."
I can't understand this part. why we need to ad... |
H: Nmos trigerring in 4-20mA converter
Here is the circuit I am trying to understand:
It comes from the following application note from LT:
https://www.analog.com/media/en/technical-documentation/technical-articles/D61_EN-Convert.pdf
I am wondering how the Nmos will ever be triggered. Now from my point of view, the o... |
H: What is the purpose of a diode and resistor at the gate of a FET in this LED driver circuit?
I am trying to design a LED driver based the LM3409HV IC.
I am using the reference design from TI as a starting point.
The schematic in the datasheet has a diode (D2) and a resistor (R5) at the gate of the FET that switches... |
H: One resistor in series and two in parallel for LEDs
So I've read that using one resistor to limit current to two or more LED's in parallel is bad practice, so I wondered what about this kind of circuit:
Is this also bad practice?
Each LED has it's own current limiting resistor, but the current is being limited fu... |
H: Discriminate MOS from BJT easily
I have a transistor for which no datasheet is available
the transistor is supposed to be NPN (which implies BJT).
(BD247C-Transistor-NPN, 100V 25A, 120W in TO220)
how can I find out easily if it's a MOS or if it's a BJT?
I have a Digital multi meter and a +5,+12V power supply.
AI: ... |
H: If a circuit only has a current source and no voltage source where does the voltage come from to supply the circuit?
For example this circuit, A current source is something with would alter the voltage across it to meet a certain current.
But where is there a voltage source to do this or even have a voltage at Vx... |
H: LED behavior during 24 VAC negative half cycle
I don't understand why the green portion of LED3 is able to conduct. Since the path marked in green represents the negative half-cycle of the 24VAC isn't the green LED reverse biased therefore no current flow. Isn't the red portion of LED3 FW bised- shouldn't it be lit... |
H: Bad Practice - Charging Lithium-ion Batteries while powering circuit?
I'm using a 2s BMC (Battery Management Control) to charge a 2s2p lithium-ion battery pack (7.4v, ~6Ah). The output of the charging circuit is the same as the input - they're not separate. As a result, when I want to charge the batteries, I just... |
H: Impedance matching a dual frequencies
Does anyone know of any impedance matching techniques to match at two different frequencies? Where the impedance at both desired frequencies are different (both the real and imaginary components)?
Most of the papers regarding dual impedance matching assume that the impedance i... |
H: 7 Segment Display Segment C Kmap Confusion
I am working on the Kmap for the Segment C on the 7 Segment Display.
The list of numbers that light up the 7 segment displays segment C are as follows:
The Kmap I came up with, without grouping yet, is as follows:
Then, when I start grouping, I came up with multiple vari... |
H: ESD/overvoltage protection with DM1231-02SO TVS array
I'm protecting a USB2.0 IC against ESD and overvoltage at the USB connector using a Diodes Incorporated DM1231-02SO TVS (dual) array. The datasheet labels the pins IN and OUT, but it's not 100% clear which of those should be on the USB connector side and which o... |
H: Interfacing an LPC2148 with a CAN module
I need to implement the CAN protocol to communicate between two LPC2148s. Now I am planning to use SPI for communication between a microcontroller and a CAN controller and then the CAN protocol for communication between two nodes.
Why do we need CAN transceivers? What does a... |
H: Using PWM instead of real DC for VFD's 0-10V control input
There is a VFD which controls an AC motor through a 0-10V control. I know that this control voltage is DC voltage.
I'm wondering would a PWM work for this application? I mean instead of 2VDC, what happens if one applies 0-10V 500Hz pulse train with 20% duty... |
H: Elements' order in a circuit
I was reading about source transformations and came across an example where there was a change in the order of two series elements, is this always possible? The same for in parallel elements but that makes sens since they have the same voltage.
AI: Yes, you can always swap the order of ... |
H: Is this current clamp meter measuring correct according to its specs?
A 24V DC power supply is supplying around 2.4A to a pure resistive load.
The input voltage is 230Vrms. So I estimated the rms current drawn from the power network as:
P/230 = (24*2.4)/230 = 250mA.
And with a multimeter this current is measured a... |
H: Vivado simulation stuck at 0 fs
I am trying to simulate a D flip flop using Vivado 2018.2.2.
But upon running the simulation a window pops up stating Current time: 0 fs. The program doesn't freeze, it just doesn't progress. Here is the code:
LIBRARY IEEE;
USE IEEE.std_logic_1164.ALL;
ENTITY Dff IS
port (d, clk... |
H: Why the voltage suddenly reduces when thyristors change from forward blocking to conduction mode
As per the diagram:
v-I characteristics of SCR is a graph of anode current I A on y-axis & anode to cathode Voltage plotted on x-axis v-I characteristics can be split into two parts namely Forward Characteristics & Rev... |
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