| Title |
[SPECIAL ISSUE] A Sub-threshold based 747 nW Resistor-less Low-dropout Regulator for IoT Application |
| Authors |
Fatemeh Abbassi(Fatemeh Abbassi) ; SungJin Kim(SungJin Kim) ; Abdolhamid Noori(Abdolhamid Noori) ; Ji-Hyeon Cheon(Ji-Hyeon Cheon) ; Truong Van Cong Thuong(Truong Van Cong Thuong) ; Truong Thi Kim Nga(Truong Thi Kim Nga) ; Kang-Yoon Lee(Kang-Yoon Lee) |
| DOI |
https://doi.org/10.5573/JSTS.2019.19.3.239 |
| Keywords |
Subthreshold region ; low power ; band gap reference circuit ; low-dropout regulator ; resistor-less |
| Abstract |
This paper presents a curvature-compensated Band-Gap reference used as a reference voltage for a Low-Dropout Regulator. The circuit is totally implemented with only MOS transistors functional from 1.8 V to 3.6 V for Internet of Things (IoT) applications. In designed Ultra-Low Power (ULP) BGR, only one stage high slope proportional-to-absolute temperature (PTAT) voltage generator is employed to compensate complementary-to-absolute temperature (CTAT) voltage generated in the current reference. In addition, cascode tail current is utilized to improve Power Supply Rejection Ratio (PSRR). The proposed BGR-LDO uses only the MOSFETs in the subthreshold region to greatly reduce power consumption, in the other words, BJTs and resistors are removed. Therefore, not only consumed power decreases significantly, but also occupied chip area declines. The proposed BGR-LDO circuit fabricated in a 55 nm CMOS process. It consumes 747 nW power for input voltage of 3.3 V. The measurement results illustrate -55 dB power supply rejection ratio, a TC of 16 ppm/°C within a range of the -40°C to 80°C and line regulation of 4.4 mV/V for supply voltage variation from 1.8 V to 3.6 V. Load regulation is 0.8 mV/mA for load current variation form 0 A to 10 mA. The active area is 190 μm × 390 μm. |