A Temperature-Compensated, Low-Power, Microsecond-Response Power Gating Circuit With Triple-Mode Overload Protection

This paper presents a power gating circuit with triple-mode overload protection, which can be integrated into low power charger or regulators for interface protection. It can respond in tens of microseconds while consuming 0.8μA quiescent current under low-power mode (LPM) conditions. A voltage-to-resistance converter (VRC) is proposed to generate a resistance inversely proportional to the input supply voltage for setting the overload threshold. A temperature compensation mechanism is also integrated to maintain overload threshold deviations within ±2% over the −40°C to 125°C range. The mode control logic implements an auto-recovery function that automatically reconnects the power gating path after the overload condition clears. Fabricated in 0.18-μm BCD technology, the design operates over a 5–40 V range with an area of 0.35 mm², achieving an RDSON of 600 mω for the integrated power switches. For over-power protection (OPP, threshold: 1.2 W), the power conduction path is turned off with a response time of 17μs under an abrupt 3 W power surge. For over-current protection (OCP, threshold: 106 mA), the path is shut down within 12 μs upon an abrupt 300 mA load current surge. For over-voltage protection (OVP, threshold: 24 V) for an abrupt voltage transition from 10 V to 40 V, the conduction path is cut off within 1 μs via slope detection.