Abstract: By adopting the BCD technology, a high precise voltage reference circuit starting-up quickly and without trimming is designed. The TTL_BUFFER using the voltage stabilizing characteristic of the Zener diode causes the variation of input voltage with voltage reference to be about 1V and improves the precision of the voltage reference. Using the self off-set characteristic, the MOS biases the voltage reference quickly, and then the fast starting-up of the whole circuit is completed. Combining the voltage reference, the circuit has its reference voltage swing of less than 2mV and a start-up time of about 20μs when the input voltage lies between 6.3V and 14V. Compared with the circuits of the same type, the output swing of the voltage reference decreases by 60％ and the start up time shortens by 40％.

Key words: bipolar CMOS DMOS(BCD), voltage reference, fast-start-up