Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

AC and DC Voltage and Current and Resistance Measuring Circuit

Status
Not open for further replies.

djranganamax

Newbie level 3
Joined
Sep 6, 2010
Messages
3
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,306
Can Anybody explain how to design a circuit for measuring " AC and DC Voltage and Current and also Resistance " using analog electronics or using a Micro controller.plz help :cry:

And mention or attach the Circuit diagrams and Datasheets that I have to reffer....

plz help me because I have no idea to measure these parameters because I have to design a Multimeter as my undergraduate Project :sad:
 

Abhishek K

Junior Member level 1
Joined
Jan 17, 2011
Messages
15
Helped
5
Reputation
10
Reaction score
5
Trophy points
1,283
Location
pune,india
Activity points
1,353
you can design it....but a dmm is way more costly if you are going to use microcntroller.
DC voltage= use ADC(analog to digital converters.)
AC voltage= use peak detector and then using microcontroller calculate the rms value .(Imax/ root(2)).

---------- Post added at 21:03 ---------- Previous post was at 21:00 ----------

for cicuits, refer Analog Circuit Designs(something like that) by sergio franco (for peak detector )
and MAZIDI for 8051(for interfacing the ADC and programing basics)
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
48,914
Helped
14,335
Reputation
28,933
Reaction score
13,080
Trophy points
1,393
Location
Bochum, Germany
Activity points
282,243
It's definitely not a good idea to calculate an AC voltage value from a peak measurement, it's effectively the method to introduce maximum error with non-sinusoidal waveforms. No existing multimeter does it this way. You have either rectified value (rectify and average) or true RMS, the latter with higher performance instruments.

I don't know your project assignment, designing a processor circuit may be possibly suggested. Benchtop multimeters mostly are using a microprocessor, but their circuits are rather complex. Classical handheld multimeters have been built around a DVM chip, e.g. Intersil ICL 7106/7107, circuits should be still flowing around the internet. Many retail instruments come with a circuit diagram, so there are plenty of options to gather some ideas. In any way, it's required for a project to understand what you are designing respectively copying, so it can't be avoided to get involved with the analog measurement circuits somewhat deeper.
 

djranganamax

Newbie level 3
Joined
Sep 6, 2010
Messages
3
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,306
Here I want to measure AC and DC Voltage and Current and Resistance and display the values in a LCD or Seven Segment Displays.:sad:

So plz give a help to design a Digital Multimeter......:cry::cry:

Plz mention about the specific Analog ICs that I can use for designing the digital multimeter that I can refer the datasheets and can get a Idea:idea:

plz help:cry::cry:
 

Abhishek K

Junior Member level 1
Joined
Jan 17, 2011
Messages
15
Helped
5
Reputation
10
Reaction score
5
Trophy points
1,283
Location
pune,india
Activity points
1,353
For RMS value, use a squarer circuit, an integrator, and a square rooting circuit... the first and last can be made using multipliers
 

nicko-391

Member level 2
Joined
Dec 8, 2010
Messages
42
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Location
Sri Lanka
Activity points
1,542
Here I want to measure AC and DC Voltage and Current and Resistance and display the values in a LCD or Seven Segment Displays.:sad:

So plz give a help to design a Digital Multimeter......:cry::cry:

Plz mention about the specific Analog ICs that I can use for designing the digital multimeter that I can refer the datasheets and can get a Idea:idea:

plz help:cry::cry:

Hve u finished the project?
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top