Why use amplifier with adc?

Started by Anonymous in sci.electronics.basics4 years ago 5 replies

I don't know very well how adc works, so i have a question. Most adc have a Vref pin that defines Vin range of adc. Vin range of adc is then...

I don't know very well how adc works, so i have a question. Most adc have a Vref pin that defines Vin range of adc. Vin range of adc is then divider for 2^n (n=resolution) to obtain LSB. If i resize Vref, new Vin range (smaller) is divided for 2^n, so LSB has smaller value.If i have a sensor, why i shoud use amplifier to drive Vin pin of adc?can i resize Vref as i like (or there is a limit)? ...


ADC Selection

Started by Fibo in sci.electronics.basics4 years ago 6 replies
ADC

Hello, I have some questions on how to go about selecting an ADC for an application. I would like to take a voltage measurement across a...

Hello, I have some questions on how to go about selecting an ADC for an application. I would like to take a voltage measurement across a shunt. 1mOhm Shunt 500-1000 samples per second If possible I'd like to be able to see 0-200A with a resolution of 5mA? I think I'm just getting information overload from Google, but maybe a 24bit Sigma-Delta? I'm not sure... not sure how to start ...


Data Rates

Started by Anonymous in sci.electronics.basics2 years ago 5 replies
ADC

Hi, I am new to electronics. So, please be patient. I am trying to figure out the following problems for past 10 hours and can not get it...

Hi, I am new to electronics. So, please be patient. I am trying to figure out the following problems for past 10 hours and can not get it solved. I need to sample six sensors after every 20 minutes using a microcontroller. Four temperature sensors and two light sensors. Each sensor is connected to the six individual pin of the ADC. This ADC is integrated into the microcontroller chip. Th...


AMP, ADC, Transistor Questions!

Started by Anonymous in sci.electronics.basics2 years ago

Hello everyone. I am picking up on a project someone else worked and and I wanted to see if anyone had some ideas on a amplifier and ADC...

Hello everyone. I am picking up on a project someone else worked and and I wanted to see if anyone had some ideas on a amplifier and ADC connection that is being made in their schematic: 1.) See the schematic here: http://i1228.photobucket.com/albums/ee460/MrBlueCalifornia/qustion_zps3ck8j17m.jpg 2.) I am using a differenctial amplifier to measure a signal (U4 and U5 of


Digital Electric Fence Tester?

Started by torg...@torgil.com in sci.electronics.basics9 years ago 3 replies

Hi! I've got an electric fence with 1Hz high-voltage pulses (2kV-10kV). I'd like to monitor the voltage from the fence using an ADC....

Hi! I've got an electric fence with 1Hz high-voltage pulses (2kV-10kV). I'd like to monitor the voltage from the fence using an ADC. Could anyone give me some ideas for a high-impedance circuit that could be connected to an ADC? Could I use a capacitor and a diode? Any ideas are welcome!


External clock for Analog to Digital Converter

Started by Bilal Amin in sci.electronics.basics11 years ago 1 reply

Hi Everyone, I am working on Jitter in Analog to Digital Converters(ADCs). I am trying to setup an experiment to see the effects of jitter in...

Hi Everyone, I am working on Jitter in Analog to Digital Converters(ADCs). I am trying to setup an experiment to see the effects of jitter in real time ADCs. I have an ADC evalutaion board with external clock input for sampling (i.e Sampling clock). Now I want to produce a self created jittery signal to see the effects of jitter in ADC. Can anyone out there have any idea(s) how I can produc...


single ended or differential input

Started by Tareq Matar in sci.electronics.basics3 years ago 6 replies
ADC

what is the difference between these configurations on an ADC ?

what is the difference between these configurations on an ADC ?


multi input multi output analog to digital converter

Started by Tareq Matar in sci.electronics.basics3 years ago 9 replies
ADC

Is there a way to convert to different signals with one ADC instead of using two separate converters?

Is there a way to convert to different signals with one ADC instead of using two separate converters?


What is an adc with pseudo-differential inputs?

Started by Anonymous in sci.electronics.basics10 years ago 2 replies
ADC

Hi. I've done some reading (eg Horowitz & Hill and other books), but I can't find an explanation to what pseudo-differential inputs is....

Hi. I've done some reading (eg Horowitz & Hill and other books), but I can't find an explanation to what pseudo-differential inputs is. Could someone explain or direct me to an application note? Thanks Juan Herrera


Battery Level Monitor

Started by Michael in sci.electronics.basics11 years ago 3 replies

Hi, I'd like to create a 12V battery monitor and interface it to a PICAXE-08M running at 3.3V. What would be the best way to do this? I...

Hi, I'd like to create a 12V battery monitor and interface it to a PICAXE-08M running at 3.3V. What would be the best way to do this? I was thinking about using a 3.3V reg for the picaxe and then use a voltage divider so the changes in voltage can be picked up using the onboard ADC. Would I be right in assuming the resistor values should be about 10Kohms and 2.96Kohms? Cheers, ...


Really old homebrew power supply

Started by Paul E. Schoen in sci.electronics.basics9 years ago 5 replies

I have a power supply that I built as one of my first projects when I was in high school, in the mid 1960s, and it has always worked well enough...

I have a power supply that I built as one of my first projects when I was in high school, in the mid 1960s, and it has always worked well enough for my needs. It's in a Bud "Portacab" 6" wide, 8" high, and 8" deep. It has 2" analog meters, 0-10 VDC, and 0-3 ADC, and a ten-turn pot for output voltage adjustment. It has a 2 wire non-polarized lamp cord for AC supply, with a fuse on one of the i...


Interfacing A Pressure Sensor

Started by Michael in sci.electronics.basics11 years ago 9 replies
ADC

Hi, I have a pressure sensor (http://www.farnell.com/datasheets/8717.pdf - page 4) which uses positive and negative pins to output the...

Hi, I have a pressure sensor (http://www.farnell.com/datasheets/8717.pdf - page 4) which uses positive and negative pins to output the pressure. As the pressure increases the (potential) difference between the pins also increase. How do I go about interfacing this to a microcontroller (Picaxe 08M - has a ADC)? Thanks Michael


Driving a PNP Darlington transistor from a PIC16F877A

Started by scouselad in sci.electronics.basics10 years ago 5 replies

Hi, I'm designing an electronically-controlled light dimmer circuit based on one I found at: http://www.edn.com/article/CA46649.html I'm...

Hi, I'm designing an electronically-controlled light dimmer circuit based on one I found at: http://www.edn.com/article/CA46649.html I'm replacing the SG3524 PWM chip with a PIC16F877A and I intend to take a digital input from the user and (scale it, then) compare it with the 0-5V from the op-amp (digitised using the PIC's ADC). As you can see from the diagram, the PWM signal drives a PNP ...