A resistorless low-power voltage reference based on mutual temperature cancellation of V_T and V_TH

ABSTRACT

In this paper, a novel resistorless CMOS voltage reference with a sub-one-volt power supply is proposed and simulated in 90 nm CMOS technology. The thermal voltage obtained from ∆V_BE is converted into a current (I) proportional to the square of temperature (T²) using a deep triode MOSFET as a resistor. A linear positive temperature coefficient part of the circuit is built by applying this current through a diode-connected MOSFET. V_TH is also used as a negative temperature coefficient part. The reference voltage is obtained from the proper combination of these two parts. The proposed circuit is designed in the sub-threshold region to reduce power consumption. Moreover, using bulk biasing and an array of MOSFETs, a trimming circuit is adopted to compensate for the process-related reference voltage variation. The nominal output voltage reference is about 0.5 V with a temperature coefficient of 25.4 ppm/^oC over a temperature range of 0 ^oC to 100 ^oC. The power supply noise attenuation of 87.5 dB is achieved without any filtering capacitor below 23 Hz at 1 V of V_dd.

KEYWORDS:

• Low voltage
• non-bandgap voltage reference
• self-biased current source
• power-supply noise attenuation
• sub-threshold

Disclosure statement

No potential conflict of interest was reported by the author(s).