Hi, we need help regarding DAC IC, we are using for our development.
We used AD5696ARUZ (Digital to Analog Converters - DAC 16 bit 4-ch 12C),
Right now we are using below configuration:
Vdd = 4.86 V, Vref = 4.86 V, Gain = 2
1. As per this configuration it's clear that, we can't get Vout at 2*Vref. It's clearly our mistake here.
Attaching schematic of design
2. Now, as part of solution we want to achieve range for Vout that's 0-5V Only. Also, let us know what is maximum output voltage this IC
can generate
Kindly refer below DAC vs Vout chart:
| Vout | ||
| DAC | Right | Left |
| 0 | 0.04 | 0.06 |
| 6000 | 0.7 | 0.7 |
| 10000 | 1.16 | 1.16 |
| 12000 | 1.39 | 1.39 |
| 14000 | 1.62 | 1.62 |
| 16000 | 1.85 | 1.85 |
| 20000 | 2.31 | 2.31 |
| 36000 | 4.15 | 4.15 |
| 38990 | 4.499 | 4.499 |
| 39000 | 4.5 | 4.5 |
| 39010 | 4.501 | 4.501 |
| 40000 | 4.61 | 4.61 |
| 40000 | 4.615 | 4.615 |
| 41400 | 4.774 | 4.774 |
| 41410 | 4.775 | 4.774 |
| 41420 | 4.775 | 4.774 |
| 41440 | 4.775 | 4.774 |
| 41450 | 4.775 | 4.775 |
| 48000 | 4.77 | 4.77 |
| 54000 | 4.77 | 4.77 |
| 58000 | 4.77 | 4.77 |
| 62000 | 4.77 | 4.77 |
| 65535 | 4.775 | 4.775 |
From above chart its clear that data is not linear.
3. Attaching code we are using for communicating on I2C interface.
from smbus2 import SMBus
class AD5696(object):
def __init__(self, Bus):
self._device = SMBus(Bus)
self._device.write_i2c_block_data(
0x0c, 0x70, [0, 0])
self.set_voltage(0, 1)
self.set_voltage(65535, 2)
def set_voltage(self, ValueDAC, SelectedChannel):
Data = [(ValueDAC >> 8) & 0xFF, (ValueDAC) & 0xFF]
if SelectedChannel == 1:
self._device.write_i2c_block_data(
DEFAULT_ADDRESS, WRITEDAC_A, Data)
updateRunTime(ValueDAC)
elif SelectedChannel == 2:
self._device.write_i2c_block_data(
DEFAULT_ADDRESS, WRITEDAC_B, Data)
Kindly look into this issue and let me know if you have any suggestions and solution on this.
