LPC54018 ADC 16-bit

[Sukumar_M]

Hi,

Why LPC54018 Microcontroller have 16-bit ADC. As per data Sheet it should be configure only 12 bit but its resolution is 16 bit the final stage of function it should be shifted.

Why?

[xiangjun_rong]

Hi,

As the following screenshot from UM11060.pdf,the ADC resolution for LPC540xx is 12 bits instead of 16 bits.

where did you know the ADC resolution is 16 bits?

BR

XiangJun Rong

xiangjun_rong_0-1657193269421.png

[frank_m]

If I remember correctly, the 12-bit result of the ADC is left-aligned within the result register.

[Sukumar_M]

Hi 

I'm worked in mcuxpresso Its configered as per data sheet is 12 bit but its shifted from this deriverd value originally its 16 bit.

from given below example:

Capture1.JPGCapture.JPG

[xiangjun_rong]

Hi, Sukumar,

The ADC data register is 32 bits, but the 12 bits sample result occupies 4~15 bits, as a uint16_t variable format, it is a left-alignment data as Frank said.

For detailed inf,pls refer to section 43.6.6 ADC Channel Data registers 0 to 11 in UM11155.pdf.

Hope it can help you

BR

XiangJun Rong

xiangjun_rong_0-1657262129409.png

[Sukumar_M]

OK,

If may use 16 bit ADC any issue

[frank_m]

> If may use 16 bit ADC any issue

I don't understand what actually the question is.

But proper PCB design for a 16-bit ADC is not trivial. A bad design can have worse accuracy and performance values than a proper 12-bit design.

My company uses 10-bit and 12-bit ADC inputs in control units for safety-certified heavy machinery.

[xiangjun_rong]

Hi,

Unfortunately, the ADC of LPC54018 has only fixed 12 bits resolution, which can not be configured. The LPC55xx has ADC which can be configured as 16 bits resolution or 12 bits resolution.

BR

XiangJun Rong