Tool/software:
Hello,
According to ADC081C021 data sheet marking code for ADC081C021CIMMX/NOPB (VSSOP package) supposed to be X36C.
What I can read from the top of the chip is 32FY X36C. Is it corect?
Regards
Hi Edi,
Since I don't know what your reference voltage is, I can't exactly tell you. For this device, the supply voltage serves as the reference voltage. What I can do is direct you to our Analog Engineer's Calculator tool, which has a bunch of great design and conversion tools, including an ADC code to input voltage calculator.
The general formula is Voltage = Reference voltage * (output code / full-scale codes)
https://www.ti.com/tool/ANALOG-ENGINEER-CALC
Regards,
Joel
Issue is that input is 3v, however I2C read is:
D15: 1
D14: 1
D13: 1
D12: 0
D11: 0
D10: 0
D09: 0
D08: 0
D07: 0
D06: 0
D05: 0
D04: 0
D03: 1
D02: 1
D01: 1
D00: 0
As per data sheet D11 to D4 value is 00, however input voltage is 3v from battery.
The values from D3:D0 don’t match the datasheet. So something is wrong... Does any other settings needs to be done before reading conversion value?
Hi Edi,
I can definitely help you out with this. Since D14, D13, D12, D3, D2, D1, and D0 are supposed to always return 0, this suggests you are reading from the wrong register (though I'm not sure from where).
Before reading the contents of the conversion result register, the address pointer register must first be set. If you are familiar with I2C, you will first provide the 7-bit device address, followed by a write bit (low), followed by a device acknowledge bit (ACK). After this, the 8-bit pointer is provided (0x00 for the conversion result register), followed by a device ACK. The address pointer register is now set.
After a restart condition, the controller again provides the 7-bit device address, followed by a read bit (high), and an ADC acknowledgment. The device then provides the first 8 bits of the conversion register, then an acknowledgment from the controller, the the last 8 bits of the conversion register. This is followed by a NACK and stop condition in normal (not continuous mode).
Above is the verbal explanation, but I prefer to share the visual representation below. This is figure 30 from the datasheet, which shows the process I described above.
I hope this helps!
Regards,
Joel
The manual says D14:D12 and D3:D0 should be all zeros, but you claiming that all 1’s
