HIGH-SPEED LOW-POWER VOLTAGE COMPARATOR TO FACILITATE AUTOMATIC COMPLIANCE VOLTAGE CONTROL FOR A NEUROSTIMULATOR
Publication Date: 2003-Jul-18
The IP.com Prior Art Database
A high-speed, low-power voltage comparator circuit facilitates automatic compliance voltage control of an implantable neurostimulator device. The circuit detects if the drain voltage of an NMOS current sink falls below the voltage of 1.2 V, which is chosen because it is typically generated by a bandgap reference circuit and is therefore readily available, and because it is sufficiently greater than the typical voltage needed across the NMOS transistor to provide enough design margin so that the NMOS transistor functions as an ideal constant current sink. The circuit provided by the invention is low-power and therefore suitable for use in implantable biomedical applications because it consumes no quiescent current other than leakage currents of the circuit components. It is high-speed because the current needed to make the comparison decision can be set as high as needed to quickly drive parasitic load capacitances internal to the circuit.