AM3352: AM3352's ADC Resistance

Kuan Wei Chen (Kevin Chen)

Genius 9710 points

Part Number: AM3352

Dear Team,

What is the AM3352's ADC resistance?

The customer is asking impedance of ADC interface AIN6 & AIN7

Kevin

over 7 years ago

0 Biser Gatchev-XID over 7 years ago

TI__Guru**** 393215 points

Hi,

See Table 5-16 in the AM335x Datasheet Rev. J. Look for parameter "Input impedance of AIN[7:0]".

0 Kuan Wei Chen (Kevin Chen) over 7 years ago in reply to Biser Gatchev-XID

TI__Genius 9710 points

Dear Biser,

If the customer want to measure it, is it possible?
How to measure it?
Or do you have test report can share to the customer directly?

BR
Kevin

0 peaves over 7 years ago in reply to Kuan Wei Chen (Kevin Chen)

TI__Guru 64935 points

The analog input is connected to a capacitor. The maximum input capacitance is approximately 10.5 pF, so the impedance value provided is simply the impedance of a 10.5 pF capacitor.

You could insert a series resistor and measure the voltage across it while applying a signal of know frequency, then calculate the input impedance. However, you need to account for the load your test equipment applies when making this measurement.

Regards,

Paul

Processors

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AM3352: AM3352's ADC Resistance