Bandgap voltage references with 1V supply

The structure, operation principle and set of circuit implementations of the low output voltage (~200 mV) bandgap voltage references are presented. References are capable for operating with a supply below 1V, while having accuracy and noise parameters comparable with the traditional 1.2 V bandgap reference. Reference's core can use substrate, lateral or vertical PNP or NPN transistors, which allows implementation on almost any process. A test reference fabricated with the 50HPA07 BiCMOS process from Texas Instruments shows untrimmed output voltages with less than 1% production scattering (3sigma). The temperature coefficient is below 20 ppm/degC while minimum supply voltage is 1 V at -40 to 125degC range