  This brief presents a technique for compensating the temperature coefficient
(TC) of a bandgap reference (BGR) using temperature characteristics of
transistor's current gain \b{eta}. As a comparison, three BGR circuits built
with Si BJTs and SiGe HBTs are implemented to demonstrate the proposed TC
curvature compensation technique. Measured average TC of the HBT proposed BGR
is 23ppm/ {\deg}C and 39 ppm/ {\deg}C over the commercial (0~70 {\deg}C) and
space (-260~125 {\deg}C) temperature ranges, respectively. With the proposed
PSRR improvement technique, the BGR reaches PSRR of -50dB at 1MHz, and -38dB at
1GHz, respectively.
