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How does a pseudo differential bipolar ADC work?
A pseudo-differential bipolar ADC digitizes the differential analog input voltage (IN+ – IN–) over a span of ±V. FS/2. In this range, a single-ended bipolar input signal, driven on the IN+ pin, is measured with respect to the signal mid-scale reference level, driven on the IN– pin.
What’s the difference between single ended and pseudo differential?
In single-ended mode you use one input only for your signal. In pseudo differential mode, a second input is used (IN+ and IN-). positive input IN+ the single-ended signal is applied. On the negative input IN- you apply a DC voltage to shift your signal.
What are the three configurations of pseudo differential?
There are three configurations of pseudo differential: unipolar, pseudo bipolar, and true bipolar. The ADI SAR ADC portfolio offers devices that provide each configuration.
How does an ADC with differential input work?
An ADC with differential inputs digitizes the voltage difference between the IN+and IN–pins while supporting a wide common mode input range. The analog input signals on IN+and IN–can have an arbitrary relationship to each other. In most differential ADCs, both IN+and IN–remain between GND and V
What’s the voltage range of a bipolar converter?
Most Analog to Digital Converters have a unipolar input that can be a problem when designing bipolar circuits. Some common ADC input voltage ranges are 0 to 2.5 V, or 0 to 5 V. However, the analog circuit that drives the ADC can have voltage swings of, –1 V to +1 V, –2 V to +2 V, –5 V to +5 V, and so on.
Can a analog circuit drive an ADC chip?
However, the analog circuit that drives the ADC can have voltage swings of, –1 V to +1 V, –2 V to +2 V , –5 V to +5 V, and so on. Bringing the ADC input below ground is a big No-No, because the current from input will flow through the chip substrate creating irreversible changes in the ADC and damage it.
What should the voltage of an ADC pin be?
An ADC with fully-differential inputs digitizes the differential analog input voltage (IN+ – IN–) over a span of ±V. FS. In this range, the IN+ and IN– pins should be driven 180º out-of-phase with respect to each other, centered on a fixed common mode voltage, for example, V. REF/2 ±50mV.