# A Sub-1-V Nanopower MOS-Only Voltage Reference

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## Abstract

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## 1. Introduction

## 2. Principle of MOS-Only Voltage Reference

#### 2.1. EKV Model

#### 2.2. MOS-Only Voltage Reference Operation Principle

## 3. Circuit Design

#### 3.1. Proposed Specific Current Source

#### 3.2. Loop Stability

#### 3.3. Output Stage

#### 3.4. Start-Up Circuit

## 4. Simulation Results

#### 4.1. Temperature Dependence before Trimming

#### 4.2. Temperature Dependence after Trimming

#### 4.3. Frequency Compensation

#### 4.4. Supply Dependence

## 5. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Conflicts of Interest

## Appendix A

## References

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**Figure 1.**(

**a**) The conceptual diagram of ${V}_{T}$-based voltage reference; (

**b**) the temperature characteristic of ${V}_{T}$.

**Figure 5.**The impact of a (current mirror copy ratio) and b (size ratio ${K}_{L}/{K}_{4}$) on the normalized charge density of ${M}_{Load}$.

**Figure 8.**Monte Carlo simulation results after trimming: temperature dependence of $\Delta {V}_{REF}$.

**Table 1.**Sizes of the transistors in Figure 3.

Transistor | Size | Transistor | Size |
---|---|---|---|

${M}_{u}$ | 0.12/20 (µm/µm) | ${M}_{10,11}$ | 4${M}_{u}$ |

${M}_{1}$ | 64${M}_{u}$ | ${M}_{12,13}$ | 5/20 (µm/µm) |

${M}_{2}$ | 52${M}_{u}$ | ${M}_{14}$ | 2${M}_{u}$ |

${M}_{3}$ | 3${M}_{u}$ | ${M}_{15}$ | 2${M}_{u}$ |

${M}_{4,5}$ | 1${M}_{u}$ | ${M}_{16}$ | 5/20 (µm/µm) |

${M}_{6-8}$ | 5/20 (µm/µm) | ${M}_{Out}$ | 3 × 5/20 (µm/µm) |

${M}_{9}$ | 104${M}_{u}$ | ${M}_{Load}$ | ($\frac{1}{4}$∼$\frac{47}{64}$)${M}_{u}$ |

Parameter | This Work | TCASII’23 [1] | TCASII’23 [15] | TCASII’21 [32] | SBCCI’20 [14] | JLPEA’18 [18] |
---|---|---|---|---|---|---|

Process (nm) | 55 | 180 | 65 | 180 | 130 | 350 |

Temp. Range (°C) | −40–120 | −10–100 | −20–80 | −40–85 | −40–125 | −70–85 |

TC (ppm/°C) | 21.7 | 90 | 79.4 | 60.86 | 28.8 | 42 |

${V}_{REF}$ (mV) | 474.4 | 288 | 107.2 | 985 | 575.2 | 1520 |

$\sigma /\mu $ (%) | 5.8 | 0.574 | 2.4 | 2.6 | 4.32 | 2 |

Supply (V) | 0.8–1.5 | 0.5–2 | 0.4–0.8 | 1.5–6 | 1–1.8 | 1.7–3.3 |

LS (%/V) | 0.011 | 0.23 | 0.54 | 0.003 | 0.071 | 10 |

Consumption (nW) | 23.2 | 0.5 | 56.7 | 63 | 36.4 | 1110 |

PSRR (dB) | −89 (@100 Hz) | −45 (@100 Hz) | −66.5 (@10 Hz) | −93.3 (@10 Hz) | −54.4 (@100 Hz) | −35 (@100 Hz) |

Area (mm^{2}) | 0.009 | 0.0029 | 0.0084 | 0.015 | 0.0078 | 0.06 |

Components | 1 Type MOS | 3 Types MOS | MOS + Res | 2 Types MOS | 1 Type MOS | 2 Types MOS + Res |

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**MDPI and ACS Style**

Wang, S.; Lu, Z.; Xu, K.; Dai, H.; Wu, Z.; Yu, X.
A Sub-1-V Nanopower MOS-Only Voltage Reference. *J. Low Power Electron. Appl.* **2024**, *14*, 13.
https://doi.org/10.3390/jlpea14010013

**AMA Style**

Wang S, Lu Z, Xu K, Dai H, Wu Z, Yu X.
A Sub-1-V Nanopower MOS-Only Voltage Reference. *Journal of Low Power Electronics and Applications*. 2024; 14(1):13.
https://doi.org/10.3390/jlpea14010013

**Chicago/Turabian Style**

Wang, Siqi, Zhenghao Lu, Kunpeng Xu, Hongguang Dai, Zhanxia Wu, and Xiaopeng Yu.
2024. "A Sub-1-V Nanopower MOS-Only Voltage Reference" *Journal of Low Power Electronics and Applications* 14, no. 1: 13.
https://doi.org/10.3390/jlpea14010013