Abstract A novel topology low-voltage high precision current reference based on subthreshold Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs) is presented. The circuit achieves a temperature-independent reference current by a proper combination current of two first-order temperature-compensation current references, which exploit the temperature characteristics of integrated poly2 resistors and the I-V transconductance characteristics of MOSFET operating in the subthreshold region. The circuit, designed with the 1st silicon 0.35 µm standard CMOS logic process technology, exhibits a stable current of about 2.25 µA with much low temperature coefficient of 3×10−4 µA/°C in the temperature range of −40~150 °C at 1 V supply voltage, and also achieves a better power supply rejection ratio (PSRR) over a broad frequency. The PSRR is about −78 dB at DC and remains −42 dB at the frequency higher than 10 MHz. The maximal process error is about 6.7% based on the Monte Carlo simulation. So it has good process compatibility.
YU Guo-yi, ZOU Xue-cheng. A novel low-voltage high precision current reference based on subthreshold MOSFETs. Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2007, 8(1 ): 8-.
