LPC Microcontrollers中的主题 Re: LPC55S16 - ADC

LPC55S16 - ADC

Dhaya — Tue, 17 Oct 2023 03:57:04 GMT

Hi,

I'm using LPC55S16 (100 pin package) and configured the ADC in 16-bit resolution. While reading the value, ADC value get oscillated more. How I can reduce the oscillation?. Even if i used average of 50, it gets oscillated. Kindy resolve it, if it is possible

Re: LPC55S16 - ADC

xiangjun_rong — Tue, 17 Oct 2023 07:03:32 GMT

Hi,

Can you explain what the ADC sampling results oscillation is? If you sample a DC voltage, does the ADC sampling results oscillate? or just the low 3 bits oscillate for every ADC results.

XiangJun Rong

Re: LPC55S16 - ADC

Dhaya — Tue, 17 Oct 2023 10:52:22 GMT

Hi @xiangjun_rong ,

Here we used DC voltage samplings (max. 3.3V) and taken average of 50. Oscillating of value for current and previous value is about +/-80. We used it to verify linear POT which datasheet is attached here

Re: LPC55S16 - ADC

xiangjun_rong — Wed, 18 Oct 2023 07:11:35 GMT

Hi,

Pls refer to the spec of ADC of LPC5516,the ENOB is 12.1 bits in 16 bits resolution and single-ended mode, in other words, the low 4 bits is random, the random value is 16 LSB.

But you said that the Oscillating of value for current and previous value is about +/-80 LSB, it is too big, can you share the analog circuit and external analog source impedance?

XiangJun Rong