| IP개요 |
This study aims at presenting a novel integrated BiCMOS amplifier and a current sensing circuit for a high accuracy and high performance DC-DC boost converter. A high gain amplifier and an accurately sensed inductor current are obtained in the feedback control circuit. The proposed current sensing circuit uses a simple current mirror instead of an opamplifier as a voltage follower so that it can provide high accuracy without the reduction of power efficiency. The chip is fabricated from the 0.18 µm 1-poly 6-metal BiCMOS process. Bipolar transistor is applied to the current sources of the sensing circuit to obtain high current driving capability. The measurement shows that the current sensing circuit operates with an accuracy of higher than 92 % at the frequency of 50 KHz. The converter with a chip-size of 1 mm2 operates at the output voltage of 4 ~ 7 V with minimum power consumption of 59mW. The H-SPICE simulation results demonstrate the validity of both the current sensor and the error amplifier that are proposed in this study. |
