i would like to develope a DAC 0800 ic tester..how can i test a dac ic?

 

Build an 8-bit binary synchronous counter circuit clocked by a 555 timer circuit and apply the 8 bits to the input of the DAC.

 

Build an 8-bit binary synchronous counter circuit clocked by a 555 timer circuit and apply the 8 bits to the input of the DAC.

how can i compare the output and input..to find error?

 

Measure the output on a digital voltmeter.

 

sory..i just want to make it as a ic tester equipment..just like an ic tester..

 

What are you testing?

 

how can i relate the input applied to dac and output obtained from dac...i know that for each binary input there will be different voltage levels ..so my idea is to find any deviation from the output voltage for particular input can be considered as a error
for example
for a good working dac when ever i apply 10000000 at input suppose there will be an output 9v
for another ic (faulty one) if got 5v with all same parameters that is an error..
so i want to check all the 8bit input combinations inorder to ensure all combinations are working

 

Put eight toggle switches on the digital inputs. Read the output voltage on a DVM.

 

mrchips i already mentioned that i want to devlope it as an equipment ..it shoud be userfriendly..icluding only one "test "switch is prefered...

 

You mean to say you wish it to be an automated process. You didn't say that before.

Output 8 bits from a computer and read the voltage using an ADC or digital voltmeter with a minimum of 12-bit resolution.

 

You mean to say you wish it to be an automated process. You didn't say that before.

Output 8 bits from a computer and read the voltage using an ADC or digital voltmeter with a minimum of 12-bit resolution.

why 12bit adc? 8bit adc is enough?

 

How are you going to measure ½-bit errors? You want the ADC to be better than the DAC by at least 2 bits.

 

Something I did when I started to deal with DACs was to run them driven by a counter and check the output with a scope for linearity.

Not sure about fine details but I could see easily how it worked. More or less what you do when implementing an R2R network.

 

Something I did when I started to deal with DACs was to run them driven by a counter and check the output with a scope for linearity.

Not sure about fine details but I could see easily how it worked. More or less what you do when implementing an R2R network.

how i can test linerity?

 

how i can test linerity?

The same way you test any dataset for linearity. If the points are within some small deviation from the equation of a straight line then the dataset is linear. You test this by selecting a sample and calculating the mean deviation from the equation of the line and the variance of those deviations.

The freeware language `R' is really helpful with this stuff.
http://www.r-project.org/

 

Something I did when I started to deal with DACs was to run them driven by a counter and check the output with a scope for linearity.

Not sure about fine details but I could see easily how it worked. More or less what you do when implementing an R2R network.

The same way you test any dataset for linearity. If the points are within some small deviation from the equation of a straight line then the dataset is linear. You test this by selecting a sample and calculating the mean deviation from the equation of the line and the variance of those deviations.

The freeware language `R' is really helpful with this stuff.
http://www.r-project.org/

How are you going to measure ½-bit errors? You want the ADC to be better than the DAC by at least 2 bits.

check the circuit i have drawn ..it is for testing a dac ic..the concept is that a dac ic convert digital input to analogue and this analogue is passed to the adc..and the obtained digital output is compared with the input ..when the sequence input and output is same its clocked the flipflop to count next state and so on..i wish to use johnson counter when ever there is a mismatch between input and output the counting is stopes and fail indication led is lights..when counting a set of sequence completed it is driven to a pass indication led(i forgot to add a not gate besides that led leav it)..please help me to develop the circuit..and tell me any errors in this..

 

Hello,

The choice of an 741 in your circuit is not so good.
It has quite some offset and noise.

Bertus

 

Are you and hamed_azhar working on the same project?

http://forum.allaboutcircuits.com/threads/help-with-adc-tester.107470/

Then consider getting something like myDAQ or USB-201

and google ADC DAC testing

 

Hello,

The choice of an 741 in your circuit is not so good.
It has quite some offset and noise.

Bertus

i wil replace it with other opamps..is there any other problem>?

 

Hello,

Why do you post such large images?
I did reduce it to about 600 Kb, but you have put up the 2.5 Mb again.
Not everybody is pleased with that huge image.

Have a look here to select an opamp:
Op Amps

Bertus