A 210nA Quiescent Current Bandgap Reference with 5mA Load Capability Using Shared Error Amplifier

Abstract

This paper presents an ultra-low quiescent current bandgap reference (BGR) with current loading capability. Based on sharing an error amplifier (EA) between the BGR core and the power transistor driving circuit, the maximum load current of the BGR is extended to 5mA without relying on an output buffer. The BGR uses a dual-clamping structure to achieve low temperature coefficient (TC) and improved DC regulation. The proposed BGR is designed in a standard 0.18-µm CMOS process. Measurement results show that the input voltage range is 1.68V -2V while the output voltage is 1.19V. The quiescent current is 210nA with a maximum load current of 5mA. In the temperature range of - 40°C to 125°C, the TC of the output voltage is 9.7ppm/ °C and 30. 76ppm/ °C at the light and heavy loads, respectively. Good line and load regulations are also achieved.