AREA-EFFICIENT REVERSE VOLTAGE PROTECTION FOR LOW DROPOUT REGULATOR

This paper presents area-efficient reverse voltage protection (RVP) scheme for low dropout (LDO) regulator. The modified floating-well bulk-biasing scheme is proposed to protect the internal circuits from reverse supply voltage. The proposed scheme, which exploits Schottky Barrier Diodes and current-limiting resistors, can achieve small area, high latch-up immunity, and low voltage drop. A LDO regulator with proposed RVP scheme is also fabricated. The area portion of the RVP scheme is only 2.5 % in the fabricated LDO regulator. When reverse voltage supply of -16V is applied, reverse current of 10.22 mA is bypassed, and internal circuits are protected. When over voltage supply of 16V is applied, the internal supply voltage is regulated to 5.8 V. The proposed RVP scheme protects the internal circuits even in the reverse supply voltage with small area penalty and high latch-up immunity.