Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [drift]

55 questions
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2 answers

Why do compass chips in cellphones require frequent calibration?

Most cell phones offer digital compass functionality which uses a 3-axis magnetometer chip for data. Phones (some more than others?) frequently require the user to "recalibrate", which involves rotating the phone in a "swirly" or other pattern to…
uhoh
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How does the CMRR of difference amplifier ICs change over time?

When designing precision analog circuits, I often come across parts which seem to be more than accurate enough for my purposes, but where the datasheet does not specify how key parameters will change over time. Right now, I am looking at datasheets…
Medo42
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6
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4 answers

LED intensity changes with time

I want to operate a UV LED at continuous 20mA for one week. However, when I measure the LED intensity with a photodiode (see image), I find that the light intensity changes continuously in time. I would like to ask you how I can reduce the light…
Andrea
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Drift with Madgwick algorithm with fast movements

I am trying to correctly track orientation of a sensor with accelerometer and gyroscope using the open source Madgwick algorithm. The algorithm returns quaternions which represent the rotation between the internal and external frames and I use it to…
tristan
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3 answers

Output Drift of an operational Integrator

R = 1k and C = 0.1 uF In practice, the output of an operational amplifier integrator will (drift) until it saturates at a value close to one of the supply voltages, even when the input voltage (Vin = 0). Why does this happen? How can we prevent…
Hilton Khadka
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5
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4 answers

Calculating error between two clocks?

I have a clock. It generates ticks. I want to know the error in PPM relative to another clock, so I count the ticks. Let's say the oscillator is 1 MHz (for simplicity). I should count 1,000,000 ticks per second. I plot the (expected_tick_count -…
ajs410
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Is the current in reverse biased PN junction due to drift or diffusion?

Wikipedia says The saturation current (or scale current), more accurately the reverse saturation current, is that part of the reverse current in a semiconductor diode caused by diffusion of minority carriers from the neutral regions to the…
Kashmiri
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Gyroscopic Drift Correction

I'm currently working on a project where I am pulling readings from 3 Gyroscopes (STM L3G4200D) to a Microcontroller (TI MSP430) and sending orientation data to the user. I've been reading up on gyroscope data collection and it sounds as though…
HideAndGoSeak3
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4 answers

Basic Frequency Control Circuit

How does R4 prevent the output voltage drifting towards one of the supply rails to the op amp? I understand that R4 has to have a high resistance but I do not know why? Here is the schematic which is puzzling me: The link to the CircuitLab…
user1083734
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1 answer

Typical Resistance Temperature Coefficient Variance between a reel of same value resistors

I have a resistor divider, I'm interested calculating the drift of the divider over temperature and if possible minimizing it. I was wondering if both resistors in the divider have the same value picked from the same reel, can I assume that the…
Ali80
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1 answer

Cancelling drift of a gyro by mounting?

I am trying to design a device that is used for capturing rotation. I think I will be using an IMU from Invensense, as I have a few of them to play with. A big problem gyroscopes seems to be drift, particularly yaw drift, as the drift on pitch and…
varesa
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ds1307 drift too big

I have a RTC ds1307 mounted on a prototype board ( the one with 3 pin stripped ), and I'm experiencing a delay of about 5 sec/day, far too big compared to some research I did. Can that delay be caused from extra capacitance added by the prototyping…
Felice Pollano
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How to minimize the effect on DNL error from this opamp circuit?

By using the following single LM324 circuit, I create amplified bipolar outputs from a 16-bit 0-3.3V DAC output as follows: My aim is to minimize extra DC error due to the above LM324 circuit especially not to increase the DNL at the final output.…
GNZ
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Why passive component has better drift characteristics than active components had?

I came across this paragraph in the classic reference Op Amps For Everyone by Ron Mancini where it says on the first page: Many attempts has been made to make a stable amplifier, but temperature changes and power supply voltage extremes experienced…
KMC
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How to resolve the drift around the z-axis in an IMU6050 gyroscope?

Using the IMU6050 IMU, one can use the accelerometer to calibrate for the drift in x and y rotational axes by applying a complementary filter. However, I haven't found a way to calibrate for the drift in the z direction. If it's drifting, eventually…
ShoutOutAndCalculate
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