Confused in Choosing MCU having higher sampling rate!!

[Vaibz27]

Hi,

I am looking for a microcontroller which could take 1000 samples from sensor within 10ms. Can also anyone can help me who to calculate using the operating frequency?

 

[danadakk]

What is resolution you want for the A/D ?

These will do 1 Msps, 12 bits, SAR, and what is also onchip (multiple copies in many cases) :

PSOC 5LP, 4 a reduced set, 6 dual core.....


Regards, Dana.

 

[FvM]

10 kHz sampling rate is possible with many uC, e.g. PIC18. Acquisition can be triggered by a timer. You probably want a uC with larger RAM capacity to store the samples.

 

[thannara123]

According to the datasheet of each controller ,
You have to know what is the sampling time of your controller (see data sheet )
Also deponds the ADC clock cycles

For example

Tconv = Sampling time + 12.5 cycles
Example: With an ADCCLK = 14 MHz and a sampling time of 1.5 cycles: Tconv = 1.5 + 12.5 = 14 cycles = (14cycles/14MHz) = 1 µs

So 14cycles take 1 micro second ie 1 reading of ADC @ 14MHz
ie, for 1000 samples takes 1milli second .

 

[KlausST]

10 kHz sampling rate is possible

But OP says 1000 samples in 10ms. My maths says 100 kSmpl/s.


Klaus

 

[FvM]

But OP says 1000 samples in 10ms. My maths says 100 kSmpl/s.

Right, thanks for correcting. So standard PIC18 is out of play. PIC24, dsPIC and STM32 can do, they also have lot of RAM and - except for PIC24 - DMA features.

 

[doraemon]

Hello!

But we don't know if the sensor is analog or digital. If it's analog, yes, it's fast with the ADC and DMA,
then you get an interrupt every half buffer which allows some continuity.
If it's digital and with a significantly long frame, for instance in SPI, then it takes time.

Example: 10 MHz SPI, 40 bits frame -> 4µs per sample. Maybe with a timer + DMA, not sure.

Dora.