The tag has no wiki summary.

learn more… | top users | synonyms

1
vote
1answer
108 views

ADC Reading is much lower than expected

I am using a EFM32GG990 microprocessor and I am trying to get it to read a voltage using it's on-board ADC. I have made a circuit that I wish it to measure, both the loaded and open circuit voltage ...
0
votes
2answers
53 views

How to hook up a load cell to an Instrumentation amplifier correctly

I am trying to get load cells connected to an instrumentation amplifier. The load-cells I have are extremely similar to the ones here https://www.sparkfun.com/products/10245. They have 3 wires coming ...
3
votes
1answer
55 views

how to select capacitor for a crystal oscillator

Here is a 32 MHz crystal from one of TI's reference design The BOM list defines the crystal as ...
0
votes
0answers
30 views

Solar charger under rapidly varying conditions/impendance

My solar equipment consists of: Solar panel capable of: 20V Peak / 3.6A Peak Li-Ion Battery pack: 8.7V, 9Ah, (2S3P setup) My solar charger setup consists of: 5A DC-DC BUCK converter (XL4015) ...
2
votes
1answer
40 views

Differential amplifier with active load Sedra Smith

I'm studing differential amplifiers on Sedra Smith book, and I have come across the following circuit. My question is: how can NMOS transistor \$Q_2\$ have a current \$g_{m2}\cdot v_{id}/2\$ if the ...
0
votes
0answers
42 views

How do I determine what size generator I need?

What are the number of factors and considerations to be taken into account before sizing a prime rated generator? I am having a situation where I would be having 3 motors of 10 kW each and all these ...
0
votes
1answer
30 views

Capacitive load at the output for analysis of CMOS cells

This question is very rudimentary one. Please point me to the link if this question has been already asked. In general, when working with simulations and and analyzing the standard cells designed ...
1
vote
1answer
79 views

Level Shifting & Amplification

I am trying to design a crane load (Weight) measuring unit using motor current measurement technique. For some reasons we can't use load cells here. Part of schematic I have drawn here An air core ...
3
votes
3answers
326 views

Is a protection diode needed for a resistive load?

In some applications a flyback diode is added parallel to the load. Is that because the switching causes reverse voltage for inductive loads? What if we have a resistive load instead? Do we still need ...
0
votes
1answer
60 views

Transformer size?

How can I set the size of a transformer for a cooling fan project? The load is 100A, the power supply is 125A, we will take input from 230Ac 60Hz. Incoming two phases and outgoing also two phases but ...
11
votes
1answer
318 views

Capacitor exploded - why?

Recently I had an explosion on my desk. A 220uF 25V electrolytic capacitor just blown up shortly after attaching a load. The high-level connection was: Phocos CA08 (solar charger controller) -> ...
0
votes
1answer
114 views

Motor Control For Overload

I am using PIC 18F45K80 for four phase dc motor control operation. The maximum load current is 30 Amps. If it exceeds 30 Amps, I have to call stop_motor() function in my coding in order to switch off ...
0
votes
0answers
53 views

Battery-load query

Imagine the following circuit. The load consumption varies during the time (during a minute it has 3 different current consumption). When the DC source generates power, where does this power go? (to ...
1
vote
1answer
54 views

Maximum load current that is still indistinguishable from battery self-discharge

I am designing an electronic device that will be powered by a battery, and I am trying to keep my device's current draw in standby to a minimum. Specifically, I would like to keep the current just low ...
0
votes
1answer
71 views

How to correctly edit a system to increase per-unit voltage of a bus [PowerWorld Simulator]

I have created and simulated the following energy system using PowerWorld Simulator 17 (please download the picture if it's not clear). Now, I was given the requirement that every bus should have ...
4
votes
2answers
98 views

Why use asymmetrical capacitor values for crystal?

Are there any circumstances where you would want asymetrical load capacitors on a crystal? I came across this schematic in the documentation for an NXP UART. It looks just wrong to me. Can anyone tell ...
3
votes
1answer
196 views

Load cell, help

I am using load cell, from here. Load cell specification are mentioned on the site. 5 wire coming out, its a 4 wire core shielded load cell. What screwing thing i am facing is: Getting same voltage ...
0
votes
3answers
177 views

How to calculate power supply for 100x loads @ 3V 700mA

I'm currently designing a setup using 100x loads that requires a 3V 700mA supply ea. The loads are connected in parallel with the main power supply. I'm a bit doubting about my power supply dimension ...
0
votes
1answer
89 views

Instrumentation amplifier for load cells

In the most part of tutorials I see they use INA125 as the instrumentation amplifier for load cells. Is it ok to use another cheaper amplifier as the AD8237? Or is there a specification or ...
1
vote
1answer
83 views

Does this loadcell's creep mean that I can not let a constant load on the loadcell?

I want to build a connected scale that I can set coffee powder (for example) on it and check over the internet how much of coffee I still have without going to see it. Usually all loadcells have a ...
1
vote
3answers
162 views

Load Resistor across Crystal

What is the purpose of using a 1M Ohm resistor across crystal pins? Please refer to the image for clarity. The crystal serves as the clock source for an USB Hub device(LAN9512). There is nothing ...
0
votes
1answer
79 views

Power opamp 'floating' output

So I had to design an amplifier with a 'floating' output. (I don't know if floating is the right word, it's the direct translation from dutch.) See the picture below ( I drew it whilst sitting in the ...
1
vote
1answer
85 views

How will I know the Power Efficiency of a load?

I have a thevenin circuit with a source load. How will I get the Pin and Pout?
0
votes
0answers
106 views

Parasitic inductance causing large current spike

I'm studying the performance of electrodes in methanol fed with a pulsed DC power supply. By this I mean the power supply is being turned on and off in a controllable frequency and duty cycle. If I ...
1
vote
3answers
210 views

Input Protection for an Electronic Load

I'm currently working on a dummy load designed for testing small power supplies less than about 10V. I'd like to provide reverse input protection to prevent the op-amps from being damaged. Because the ...
1
vote
2answers
126 views

Isn't there a Voltage drop across a resistor?

I've been reading this Wikipedia - Electrical Load topic and there is a section which is confusing me... So what you do is go to the "A more technical approach" section in this topic and then read the ...
2
votes
3answers
244 views

How do you drive a high current load from a moderate current source?

If I have a power supply that can supply 5A @ 12V and I need to be able to supply an inductive load with 20+A @ 12V, how would I go about this? I need a burst of current for about 2-5 seconds. Will ...
1
vote
1answer
49 views

Replace Current controlled Voltage Source Converter with Rectifier Diodes in ELC?

In this paper an Electronic Load Controller (ELC) for two (2) parallel generators is designed. I wish to omit the second generator and hope for simplification. Now two questions arose: (while I ...
1
vote
1answer
64 views

How can one calculate Load Regulation for a temperature sensor?

I am wondering how to calculate the Load Regulation of a temperature sensor. For example ADI's TMP37? I know how to calculate % Load Regulation from Wiki, but not sure how to get to the mC/uA units? ...
2
votes
2answers
223 views

Load-line analysis derivation

I'm trying to get a better handle on the derivation where load-line analysis comes from. This is because I have a system that essentially has two different loads operating on a single diode and I'd ...
4
votes
1answer
1k views

Arduino Boost Converter. Connecting load makes converter non functional

I am trying to build a DC-DC Buck-Boost Converter using this basic schematic and an Arduino with the analogWrite() function as my PWM generator. I only want to step up 2.4-3V to ~5V. If it's just the ...
3
votes
3answers
4k views

How can I calculate the inductance of the primary of a transformer given a specific load on the secondary?

Inductance in the primary of a transformer decreases as the load on the secondary increases. How can I calculate the inductance of the primary coil? What if it was step up or one to one ratio?
3
votes
5answers
200 views

BJT input connected to another BJT's output and loading effects

Sedra & Smith Microelectronics, example 6.10, page 390. They ask us to analyze a BJT circuit. Here it is: simulate this circuit – Schematic created using CircuitLab In the next ...
0
votes
0answers
54 views

Protect power supply from mechanical switching of load

I'm powering a resistive load from a laptop PSU. The circuit will be closed and opened using a mechanical switch. I am worried that the switching will damage the PSU due to inductances in the PSU. ...
3
votes
2answers
613 views

General 3 Phase Motor Inductance Question

I know that motors are inductive loads. Does the inductance of a 3 phase motor depend on the load on the motor?
3
votes
1answer
457 views

Complex Dummy Speaker Load Impedance

I would like to create a dummy load for this so-called "Deacy Amp": This is a low power germanium transistor / transformer driven push-pull amplifier for driving a small 4 ohm or 3.2 ohm speaker. ...
0
votes
2answers
351 views

ADC Value from load cell to MSP430 not correct

I have a 1000lb load cell (LC302 from omega) being fed through an INA125 OPAMP then to the ADC10 of a MSP430G2553 with 2.5V as reference. 2.5V is coming out of the OPAMP that's being fed into the ...
1
vote
1answer
55 views

How to understand synchronism?

In my job, I frequently compile a rough rundown of the power consumption of simple industrial plants. Here, you always encounter a "synchronism" factor, besides how many motors of which power and ...
1
vote
1answer
139 views

How could I efficiently implement this “TTL load”?

I'm attempting to test a parameter of an IC to the specifications listed in the data sheet. The data sheet describes the following load circuitry for the output: The data sheet notes that CL be ...
0
votes
1answer
68 views

Frequency and magnitude of power variations in a DC circuit.

I have a 5 V 5 A power source which is connected to a simple development board with a processor that draw current dependent on utilization. I use a multimeter that measure 1000 samples / s to measure ...
3
votes
2answers
772 views

How does a real current source change its pd to keep constant current

An ideal current source is able to change its potential difference at the output to keep the same current at the output regardless of the load imepedance there. Real current sources are able to do ...
1
vote
1answer
85 views

Saturating a BJT with an open load

Is there some drawback in having a BJT transistor saturating without a load? The scenario is this: BJT is driving a relay, but there is a switch to have the relay always on or off leaving the BJT ...
1
vote
1answer
171 views

What's the input resistance of an opto-isolator?

I need to sense if a 48 volt power supply is supplying voltage or not, I plan on doing this with a opto-isolator and I am happy with the output circuit from isolator. Can I connect the input of the ...
-2
votes
2answers
532 views

What amplifier circuit to use for a wheatstone bridge force transducer [closed]

I would like to amplify the signal from a force transducer which can measure load from 0-1500g. The object i am using is less than 1 gram. I would need an operational amplifier. I would like to know ...
0
votes
1answer
113 views

Drawing VTC from IV

So I am given the IV characteristic plot along with the resistive load circuit which looks like: The load is a 25k resistor. I want to understand how to actually do the problem which is why i didn't ...
0
votes
2answers
4k views

How to interface a digital scale strain gauge weight sensor with a microcontroller? [duplicate]

Possible Duplicate: How to interface a digital scale strain gauge weight sensor with a microcontroller How to interface a digital scale strain gauge weight sensor with a microcontroller? It ...
9
votes
2answers
13k views

Choose TRIAC snubber resistor for multi-purpose switching

I'm designing a circuit to switch a 240V AC load and haven't done a lot with AC power control before. I'm planning to use a Fairchild MC3043-M optically coupled TRIAC driver along with a BT138-600 NXP ...
1
vote
2answers
442 views

How to switch both AC and DC voltage to a load

I have a load, an electrode basically acting as a very tiny capacitance, that I want to supply a voltage or bring to ground. The voltage can be either DC, up to about mains voltage, or AC into low KHz ...
1
vote
1answer
922 views

charging battery while under load

my question applies to NiCd/NiMh battery types. Can I simultaneously charge & discharge the battery? Might it cause any harm to it? I presume there will be opposite movements of the charged ...
2
votes
1answer
543 views

Boost converter can't power load. What are the limitations?

I'm trying to power a nixie lamp with a 9 volt battery. The boost converter charges up to 160vdc, the nixie lights, but quickly goes out (or half lights) as it pulls more current ~= 5mA. My boost ...