Abstract
A bandgap reference circuit was designed to provide the reference voltage needed for a 6-bit flash analog-to-digital converter in 0.18µm CMOS. Cadence Virtuoso was used for the schematic capture of the circuits, and the Mentor Graphics Eldo Spice simulator was used for all circuit simulations. The simulation results show that a zero temperature coefficient was achieved at approximately 30ºC, with an effective temperature coefficient of less than 94 ppm from -40ºC to +125ºC over all process, supply voltage, and temperature (PVT) variations. To achieve this a resistor trim circuit was included to make small adjustments to one of the resistors in the bandgap reference circuit in order to account for manufacturing variations.