ADS7870EA

The ADS7870EA is an 8-bit resolution, voltage output serial-interface analog-to-digital converter (ADC). This device provides high-speed operation, an internal reference, and an on-chip track/hold. It is designed to offer an excellent cost/performance ratio for industrial process control, instrumentation or data acquisition applications.

The ADS7870EA operates from a single +5 V power supply and its industry-standard serial-bit interface reduces the requirement of external logic components, allowing for space and cost savings.

The ADS7870EA has several features that make it a great choice for industrial applications. The device uses a sigma-delta conversion technique that provides high resolution with a low power consumption. Its conversion rate is as high as 10 k samples/sec with a low distortion and noise level. Its operating temperature range is also excellent, extending from -40°C to +125°C.

The ADS7870EA also has a very wide differential input voltage range from -VREF to +VREF, where VREF is the voltage of the internal reference (2.048 V). This makes the device ideal for applications where the input signal may have a large dynamic range.

The ADS7870EA is also a low power device, with a current consumption of only 387 μA (typical) when idle and 340 mW when operating. Its power saving mode reduces the power consumption to only 15 μA. This makes the device suitable for battery-powered applications.

The ADS7870EA provides an excellent working principle based on the sigma-delta converter. In this type of converter, the input signal is compared to a reference voltage VREF. The converter encodes the results of this comparison and stores the data in an internal register. This data is then transferred to the output port using a serial interface.

The sigma-delta converter works by integrating the difference between the input voltage and the reference voltage and measuring the time required to integrate this difference. The output from the converter is then coded in such a way as to provide a high degree of accuracy. For example, if the integral of the input voltage exceeds VREF, then a one is output and if the integral of the input voltage is lower than VREF, then a zero is output. This code is then used to convert the analog signal into a digital representation.

The ADS7870EA is therefore an excellent choice for applications where high resolution, low power consumption, and wide input voltage range is required. This device is well suited to industrial process control, instrumentation or data acquisition applications.