| ??? 08/31/06 03:31 Modified: 08/31/06 03:33 Read: times |
#123415 - Some answers... Responding to: ???'s previous message |
Eugene said:
I have done some searching but i only found 2.5V being the closest value which is the LM336 diode. Is there any more accurate reference voltage diode, in my case 2.56V which is used for the Vref pin of my ADC? There's no need for a more accurate reference since the ADC0838 provides less than 8bit precision. Eugene said:
I wanted to avoid using potentiometer as the voltage divider if possible. So please let me know the model number if there is any! This potentiometer is only a symbol for the well known ratiometric measuring methode, where the input signal is a fraction of Vcc (means Vref), so that any tolerance and drift of Vcc is cancelling. Example: Assume input signal is 127/256 x Vref. Conversion result is assumed to be "01111111b". Now assume Vref is changing somehow, maybe due to drift. Would the result of conversion also change? No! It's still 127/256 x Vref, means "01111111b". Eugene said:
Also, what is diffrence between the AGND and DGND pin? Read page 43 of this datasheet: http://www.analog.com/UploadedF...C812_e.pdf Have also a look at this evaluation board, to see how the both grounds are handled on a printed circuit board: http://www.analog.com/UploadedF...PCB_A3.pdf http://www.analog.com/UploadedF...ide_A3.pdf Eugene said:
Is there a minimum detectable current required for the analogue input of ADC? What do you mean? Expand a bit... Kai |
| Topic | Author | Date |
| 2.56v reference voltage diode for ADC0838 | 01/01/70 00:00 | |
| digikey | 01/01/70 00:00 | |
| Programmable shunt | 01/01/70 00:00 | |
| why use a programmable? | 01/01/70 00:00 | |
| Some advantages | 01/01/70 00:00 | |
| I still could not find a 2.55v ref | 01/01/70 00:00 | |
| try here | 01/01/70 00:00 | |
Some answers... | 01/01/70 00:00 |