Low-power monolithic COS/MOS dual-slope 11-bit A/D converter

Abstract

A LOW POWER, monolithic COS/MOS, autostabilized, single power supply 11-bit A/D converter designed and fabricated with standard COS/MOS processing will be discussed. The chip demonstrates the use of COS/MOS linear functions (an op-amp and1 comparator) and COS/MOS digital functions in a low power chip which is interfaceable with the COS/MOS logic family. The linear op-amp techniques employed in this dcsign are also applicable to a wide class of medium speed COS/lclOS applications. Although high accuracy, monolithic P-MOS and bipolar A/D converters suitable for many situations can be purchased commercially"', COS/MOS designs can provide advantagcs when single power supply operation, very high input impedance, low power dissipation, extended voltage and temperature operation, easy compatibility with COS/MOS logic, and the low cost potential of COS/MOS are important. Until the present time, COS/MOS circuits have been used almost exclusively for digital applications. Our present studies demonstrate that COS/MOS designs can also be attractive lor combined analog/digital designs. Availability of complementary

A Highly Digital VCO-Based ADC Architecture for Current Sensing Applications

“…The DAC is the CT equivalent of . The loop gain is given by (7) The sensitivity of to input current is quantified by using the transfer function given below: (8) For large loop gain (9) The gain from to is zero at DC because of the infinite gain provided by the IIR filter. In other words, due to the presence of the accumulator.…”

“…The third and perhaps most popular technique is using a dual slope ADC architecture [8]- [10] depicted in Fig. 1(c).…”