0
votes
1answer
8 views

Connectors: Relay to Heater

Simple project: Swap the on-off switch on a coffee-maker with a relay. The relay is rated to be safe for wall power. The coffee-pot can take it, obviously. But the old crimp-on connectors that the ...
0
votes
0answers
9 views

Low-side DC shunt motor drive

I want to drive a DC shunt motor like in the picture below. The PWM circuit with optocoupler, mosfet driver etc. is not shown. This circuit works fine on 12V DC motors. It even worked when tested on ...
-2
votes
1answer
31 views

What is stc32ab IC

I have some stc32ab IC's but I cannot find any information or datasheet for them. Please give me some information and/or datasheet about this IC
0
votes
0answers
11 views

Capacitor ESR for inverting charge-pump

I am designing a inverting charge-pump to generate negative 3.3V from positive 3.3V. But in the datasheet: ADP3605 it specifies that the output ripple is calculated using the ESR of the output ...
0
votes
0answers
13 views

Altera DE2 writing to VGA

I own an FPGA (Altera DE2) that can output via serial USB text mode like telnet or USB. Now I want to learn how to write to VGA. Do I have to rewire in Qsys / builder or can I just try and find which ...
0
votes
0answers
16 views

Making a plant stable with a compensator based on given requirements

I have a transfer function of the plant modeled as the following: I'm trying to design a compensator that satisfies some requirements. a. The maximum control bandwidth (0 dB crossover frequency) ...
3
votes
2answers
115 views

What does this wiring schematic symbol mean?

I ran into this wiring symbol today and haven't been able to find out what it means. Somehow internet search of "criss-cross wire schematic symbol" wasn't especially fruitful. Is this something I ...
0
votes
0answers
21 views

Verilog 8 bit adder & testbench - not working

Resolved - After making it compileable in Quartus by naming the for loop in my8bitadder and doing Greg's fixes, the code works fine now. Thanks guys! I've made an 8 bit adder but I can't seem to get ...
0
votes
2answers
25 views

Deltron W127G Transformer

Hey I have Recently Purchased A Deltron W127G Open-frame Power supply, but I am confused on how the transformer works. And Since I do not want to blow the thing up I figured Id ask first. The ...
0
votes
1answer
18 views

Input power with PF, impedance on transmission line and transformer

I've just had and exam (Renewable Energy) and we had a problem that I'm not sure if is correct. The answers should be simple as we haven't studied tranmission lines at all. Okay, here we go. We have ...
0
votes
3answers
52 views

How common mode signal is generated in differential amplifier

I searched about common mode signal but I only got an vague idea about it like it is an noice signal generated between input signal and common ground but did not understand how it is generated in ...
0
votes
0answers
19 views

Table lamp CE marking / safety testing for sale to the public

I am designing a table lamp that uses the following components: An LED coin module (running at 3.15 watts, 8.4 to 9.75 volts) powered by a plug-in constant current LED driver that is CE marked I am ...
0
votes
0answers
9 views

DIY battery Pack Cell amperage difference

I have individually tested the capacity of ten 18650 batteries with my iCharger 4010. My question is, how much ampacity difference is ok when packing them in parallel ? The following are the readings ...
0
votes
1answer
27 views

Need help with circuit design. SIM800 GSM

Im working on a project using an arduino and a SIM800 GSM module, plus a few sensors. The next stage of my project is to design a PCB which has the essential components on it. As Im fairly new to ...
0
votes
0answers
15 views

How the current flow through the collector-base junction of an NPN transistor operating in saturation?

From what I understand, in the saturation mode of NPN transistor, both EB and CB junctions are forward biased. Now, if the voltage across CB causes it to be forward-biased, how does the current flow ...
1
vote
1answer
23 views

Enable grid-tied solar array power output during grid outage

I am getting close to investing in a micro-inverter (Enphase M250) based grid-tie solar array for my home, but am concerned I won't be able to use the solar power during grid outages. I found a ...
0
votes
1answer
29 views

Impedance phase angle relative to?

In a simple PARALLEL RC circuit with two components of Resistor 150 Ohms and Capacitor 0.000000075F (75nF). AC supply 10V at 20,000Hz. Impedance has a phase angle of -54.7 degrees if my calculations ...
0
votes
2answers
38 views

Questions about a dimmer circuit

Below is a simple dimmer circuit using a triac, a cap and resistors. As you can see, the resistor Poti changes with time and the load current change can be seen in the plot. It seems like one can use ...
0
votes
2answers
43 views

Methods of testing interrupts

I am maintaining and developing software in C for S12X micro controllers. The ISR for each interrupts (like I2C, Timer Interrupts etc) are very lengthy, like around 20 to 30 lines with several ...
1
vote
2answers
90 views

How to keep a 9 volt micro-controller ON when where is no electricity for some minutes?

I want to keep an DCcduino clone of arduino uno ON where there is no electricity for 5-10 minutes with a 9 volt battery. Is there any way to do it without ups because it costs too much?
1
vote
2answers
24 views

Instrumentation Amplifier REF pin maximum voltage

I'm a spanish engineer student doing my end-of-degree project. I need to remove the offset of a strain gauges bridge and i'm trying to make the calibration automatic, using a DAC (digital to analog ...
1
vote
2answers
33 views

Electrical Power sensor

1.I need a sensor for measuring the electrical power without cutting the isolation of a wire. Is there a such sensor? 2.Is it possible to use the magnetic field of a wire(220v) to power a very small ...
0
votes
2answers
31 views

Transform pulses per second (pps) to rpm

I have a stepper motor that turns at 5000 PPS and has a step angle of 1.8º. What would be the formula to transform these pps into rpm? Thanks in advance!
0
votes
0answers
17 views

How to model constant voltage across fuel cell

I am creating a finite element model of a fuel cell. I'm having trouble modeling the electrical component of my system - and I was wondering if any electrical engineers here could give me their ...
3
votes
2answers
109 views

Choosing connectors for PCB

I am learning Fritzing, and looking to create my first pcb. The components are fairly simple: 10x DS18B20, 1x resistor, 1x Konekt Dash. I plan to have headers to connect the Dash so it can be easily ...
0
votes
1answer
43 views

Gas Leakage Circuit

What Transistor should i use instead of SL100? thanks
1
vote
0answers
25 views

how do hybrid plasmonic waveguides work? [on hold]

I was hoping that someone could clarify the operation of hybrid plasmonic waveguides for me. what I read on wikipedia left me with some questions: If the operation is based on coupling the ...
6
votes
2answers
124 views

Is anything besides rx and tx actually used in rs232 nowadays?

Whenever I come across a PIC or even a FPGA project that is communicating over the serial port with a PC; only Rx, Tx and power are connected on the 9 pin connector and the other pins/signals are ...
0
votes
0answers
14 views

Flashing NIOS II with SPI at boot

I have a Altera FPGA, which is configured (programmed/flashed) at startup by SPI from a processor runing embedded linux. If I put a NIOS processor in the fpga, is it possible to flash the NIOS ...
0
votes
0answers
25 views

TI design - LM3478 - missing file(?)

I found TI design for LM3478 http://www.ti.com/tool/PMP10077 . I had downloaded CAD design files "PMP10077 CAD Files" and opened it with Altium Designer (viewer license). But it seems that the file ...
2
votes
2answers
218 views

How to calculate the high voltage power line trace clearance

In My application The DC supply has rating 1200V and 15A. I just want know the calculation for the trace Clarence of these Power and GND.
0
votes
2answers
31 views

9v security sensor convert to power pack

I dont have a lot of smarts on circuitry design, so this is more of a can i do it, and what should i look at using or is there is a current solution. basically we have some wireless PIR's with our ...
1
vote
0answers
37 views

Help needed please, 30A DC Mosfet PSU / Battery switch-over [on hold]

we designed a prototype to control a 24A DC motor and various other DC consumers for a client, but got stumped when asked to introduce a battery backup with charging. It is relativity ...
2
votes
1answer
63 views

How long should 8, 1.5V batteries last for?

I purchased a GPS tracker from Amazon and instead of wiring it to the car battery I would like to simply attach my own power battery pack. I am a complete noob when it comes to electronics and I ...
2
votes
2answers
231 views

Moisture adsorption on FR4 PCB [on hold]

Although the adsorption of moisture by FR4 is quite low, what is the best way to minimize it or eliminate it completely?
0
votes
2answers
38 views

Amplifiers output current

I had read in TCA0732 datasheet that its current supply can't be greater than some decades of mA (+14mA for +15V voltage supply) but it can provide 1A of current how can that be possible, the same ...
0
votes
0answers
17 views

different between solar current and battery current [on hold]

I have solar of 12vdc 1A but did not charge my phone but when replaced with battery of thesame voltage and current ,it charge it. is there what I need to add to make the solar current active? . ...
11
votes
4answers
631 views

Ceramic caps vs electrolytic. What are the tangible differences in use?

A quick google around and all I seem to be able to find are people talking about the physics & the chemistry of the capacitors but not how this affects choosing which to use. Avoiding talking ...
0
votes
0answers
38 views

How to find the resonant frequency of a human body?

I've read that the human body has resonant frequencies somewhere around 50MHz. I also think it would be interesting to look for values in other ranges like 10-100 kHz. I'm wondering how to build a ...
-4
votes
0answers
30 views

Cheap High Torque Motor [on hold]

I'm looking for a motor (brushed/stepper/stepper)(not brushless)(probably geared) that has at least 30 kg/cm of torque, less than 15 USD (I have to buy 34), less than 100 grams, and at least 60 RPM ...
0
votes
0answers
32 views

Blocking RF from reciever

I replaced the remote control receiver of my air conditioner, the new receiver communicate with the remote control via regular IR. But after few days I have noticed that the controller turn the air ...
0
votes
2answers
28 views

Does a longer stator equal more torque in a BLDC setup?

I'm interested in making something like this: http://www.vivax-assist.com/en/produkte/vivax-assist-4-0/vivax-assist_4-0.php Because it looks awesome, but for the price i could buy a motorcycle and ...
0
votes
0answers
19 views

PC 104 Use and Installation [on hold]

I have ENC 5800 board and its technical manual. Now I want to interface TFT LCD to PC104 board. For same, I need to install linux OS on PC104. Can anyone here let me know how to install linux OS on ...
0
votes
0answers
45 views

BLDC Motor : Control Speed digitally using Microcontroller

I am stuck with a logic to control the speed of BLDC Motor via Microcotroller. I have a BLDC Motor with Electronic fitted. It requires following signal to drive : +24v 0v or GND Enable ...
0
votes
2answers
54 views

What the FPGA dev board to choose: Xilinx or Altera? [on hold]

I'm very new to programmable logic world and have never worked with any HDL languages, but I certainly want to get started with FPGA. At the moment the goal is to develop/simulate simple 8bit CPU and ...
0
votes
0answers
24 views

Common Emitter BJT configuration: output characteristics

Can someone please explain to me why the curve shifts up when there is an increase in the base current Ib ?
0
votes
0answers
25 views

Arduino Serial Monitor works but not on PySerial and PuTTY [migrated]

I made simple custom arduino board using an atmega328p and the PL2303 serial to USB chip. In my arduino program, I am in a loop that sends out a string continuously. I can read this in the Arduino ...
1
vote
4answers
120 views

Why a low-pass filter applied to a square wave gives a weird wave?

When a low-pass filter acts on a square wave, the output is something similar to this: My question is simple. If the filter is a low-pass filter, it should filter all frequencies that are above ...
0
votes
3answers
42 views

50V Ceramic Capacitor for 36V Vehicle Battery

In my vehicle Battery powered system which can vary from 12V to 36V , I want to use a Capacitor of minimum 10uF on the input. I have few doubts :- Which is best for 10uF value @ 36V - ...
3
votes
5answers
1k views

Why are through holes PLATED in PCBs?

As far as I understand, through holes in PCBs are often plated, hence the term PTH. Letting red denote copper, the first figure shows a through hole which is plated, and the second figure shows one ...

15 30 50 per page