AMC1306M25: Data converters forum

lina xu

Prodigy 21 points

Part Number: AMC1306M25
Other Parts Discussed in Thread: AMC1306M05

there is some error at the current sensor data. like 0.25A dynamic error.

AVDD is 5V, about 50mV voltage ripple.

does this affect sample accuracy? how much it will impact.

9 months ago

0 Alexander Smith 9 months ago

TI__Mastermind 49871 points

Hi Lina,

Do you have a output waveform from your controller that shows the sampled data?

What is the size of your shunt resistor?

Does the error change over time or is it static 0.25A?

0 lina xu 9 months ago in reply to Alexander Smith

Prodigy 21 points

Y axis is the current, unit is A,

shunt resistor is 3m ohm,

it error is dynamic error, not static 0.25A.

0 Alexander Smith 9 months ago in reply to lina xu

TI__Mastermind 49871 points

Hi Lina,

Thank you. I would not expect a ripple of 50mV to cause such an issue.

What are your SDFM settings for OSR and clock speed?

Can you please provide scope capture of the clock and data at the pins of the SDFM?

I assume that this measurement is taken while the system is running. Is it possible to measure the input voltage of the AMC1306M25 as well, with high voltage probes if necessary, or use a known input voltage to confirm correct SDFM operation?

0 lina xu 9 months ago in reply to Alexander Smith

Prodigy 21 points

sorry, I don't know about SDFM settings. is that Firmware setting?

this measurement is taken while it is running. the input voltage is only 3mV, It is too small to measure it.

0 Alexander Smith 9 months ago in reply to lina xu

TI__Mastermind 49871 points

Hi Lina,

The clock and data from the AMC1306M05 should be connected to a controller with a sigma delta filter module (SDFM) to collect the data and decimate to output readings.