Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

PSoC™ 4 Forum Discussions

SuSh_1535366
Level 5
50 questions asked 50 replies posted 50 sign-ins
Level 5

 

Hi.

Please tell me about the offset voltage of the PSoC4200L OpAmps.
In the datasheet, the offset voltage and the offset voltage drift values are listed.
However, the values of min/max and typ are defined only for high mode, and for medium and low  modes, only the typ values are described.
What are the min/max values for these modes?

SuSh_1535366_0-1634710745411.png

Regards,

Shimamura

0 Likes
1 Solution
Vasanth
Moderator
Moderator 250 sign-ins 500 solutions authored First question asked
Moderator

Hi Shimamura san,

As we said this is not characterized. A rough estimate is that you could call  Voffset = +/- 2.0 mV maximum at medium power and +/- 5.0 mV at low power and be right the vast majority of the time, but we can't guarantee this. There are  ways to reduce errors, this includes run-time trimming of opamp parameters (through register writes) and correlated double sampling per AN2226 and AN66444. We could help in reviewing the design too . 

Best Regards,
Vasanth

View solution in original post

0 Likes
3 Replies
Vasanth
Moderator
Moderator 250 sign-ins 500 solutions authored First question asked
Moderator

Hi Shimamura san,

Unfortunately this is not characterized. Is this preventing your from proceeding with your design ? Let us know how we can help you here.

Best Regards,
Vasanth

0 Likes
SuSh_1535366
Level 5
50 questions asked 50 replies posted 50 sign-ins
Level 5

Hello Vasanth-san,

Sorry for late reply.

They are trying to use the OpAmp as a gain amplifier to amplify the sensor signal and input it to the ADC.

Since the sensor signal needs some accuracy, they want to calculate the maximum error in advance.

If the maximum offset error is not specified, the maximum error cannot be estimated for use.

Is there any kind of guideline?

Regards,

Shimamura

0 Likes
Vasanth
Moderator
Moderator 250 sign-ins 500 solutions authored First question asked
Moderator

Hi Shimamura san,

As we said this is not characterized. A rough estimate is that you could call  Voffset = +/- 2.0 mV maximum at medium power and +/- 5.0 mV at low power and be right the vast majority of the time, but we can't guarantee this. There are  ways to reduce errors, this includes run-time trimming of opamp parameters (through register writes) and correlated double sampling per AN2226 and AN66444. We could help in reviewing the design too . 

Best Regards,
Vasanth

0 Likes