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Joined: Mar 2015
introduction
In the embedded system the microcontroller has to take analogue input. Most of these are analog, temperature, humidity, pressure, such as sensors and transducers, for these sensors to interface in microcontrollers, we have to convert this sensor to digital analog output so that the controller can read it. Some microcomputer controllers have made analog-to-digital converter (ADC) so there is no need for external ADC. For microcontrollers who do not have internal ADC external ADC
Why are we using ADC for the 8051 microcontroller?
Well. If ADC is not built in 8051, then we have to use external ADC. Many ADC are available
ADC 0804
ADC 0808
ADC0808
ADC0808 ADC's most used ADC ADC is a successful estimation type with 0808 8 channels. To wit. This 8 straight conclusions can reach analog signals. The difference is the number of analog input signals in ADC 0804 and ADC 0808. I mean, in ADC 0804 we can only give one analog input. But in ADC 0808 we can give 8 analog inputs. So if you want a high number of analog sensor interfaces, please select this ADC0808.
ADC 0808, 8 is an 8-bit analog for digital converter with analog channels, that is, it can take up to eight different analog inputs. I can convert input into digital form using these three address lines. The voltage reference can be set using Vref + and Vref-pins. Step size has been decided based on fixed size. Due to the change of an entity in the production of ADC, the size of the phase of the change in the analog input is the default phase size 59 is 19.53 mV related to the reference voltage. The ADC 0808 requires an external clock to work in contrast to the ADC 0804, where an internal clock for the initial conversion of ADC's specific control signals is required, and the data output is brought to the pin when the conversion is completed , The EOC pin reduces to the end of the conversion and prepares the data for the preparation.
Features
Easy interface for all microprocessors
Metric mode or 5V DC or analog span organizes ratio with adjusted voltage reference
No zero or full-level adjustment is necessary
8 channel multiplexer with address logic
0V to 5V input range with single 5V power supply
Output TTL meets voltage level specifications
Standard hematica or 28-pin DIP package molded
28-pin molded chip carrier package