Ring-Oscillator with Multiple Transconductors for Linear Analog-to-Digital Conversion
Abstract
:1. Introduction
2. Materials and Methods
2.1. Nonlinearity in Ring-Oscillators
2.2. Proposed Multiple-Transconductor Ring-Oscillator
3. Results
3.1. Circuit Validation
3.2. Circuit-Level Impairments
3.3. Calibration Circuit
4. Discussion
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
Abbreviations
ADC | Analog-to-digital converter |
CCO | Current-controlled oscillator |
ENOB | Effective number of bits |
IoT | Internet-of-things |
VCO | Voltage-controlled oscillator |
SAR | Successive approximation register |
Opamp | Operational amplifier |
TI | Time-Interleaved |
NS-SAR | Noise-shaping SAR |
TINS-SAR | Time interleaving noise-shaping SAR |
Delta-Sigma | |
CTSDM | Continuous-time modulator |
VCO-based ADC | Voltage-controlled oscillator-based analog-to-digital converter |
MASH | Multi-stage noise shaping |
THD | Total harmonic distortion |
PVT | Process, voltage and temperature |
ABW | Analog bandwidth |
HD3 | Third harmonic distortion term |
HD5 | Fifth harmonic distortion term |
HD2 | Second harmonic distortion term |
SNDR | Signal-to-noise-distortion ratio |
SNR | Signal-to-noise ratio |
INL | Integral nonlinearity |
LSB | Least significant bit |
NUS | Nonuniform sampling |
DSP | Digital signal processing |
CDF | Cumulative distribution function |
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Parameter | [3] | [9] | [19] | [23] | [25] | [32] * | [36] | [37] * | [38] | [40] | This Work |
---|---|---|---|---|---|---|---|---|---|---|---|
Meas./Sim. | MR | MR | MR | MR | SR | MR | MR | MR | SR | MR | SR |
Results | |||||||||||
Supply [V] | 1.2 | 1 | 1.2 | 0.9 | 1 | 1 | 1.2 | 0.2 | 1 | 0.6 | 1.2 |
Process [nm] | 90 | 28 | 130 | 40 | 65 | 65 | 65 | 28 | 28 | 65 | 65 |
BW [MHz] | 105 | 50 | 20 | 40 | 5 | 200 | 37.5 | 0.061 | 10 | 25.6 | 50 |
SNDR [dB] | 35.89 | 67 | 67 | 59.5 | 75.7 | 57 | 70 | 68 | 62 | 50.3 | 63 |
THD [dBc] | – | −74.4 | −67.7 | −65.7 | −80.7 | −63.6 | −76 | −72.5 | – | −53.9 | −66.4 |
INL [LSB] | −2/0.44 | – | – | – | – | – | – | – | – | −1.9/1.6 | −0.44/0.26 |
ENOB | 5.67 | 10.85 | 10.84 | 9.59 | 12.3 | 9.18 | 11.34 | 11 | 10 | 8.06 | 10.17 |
Diff. Input Range [mV] | 280 | 2000 | 180 | 715 | 1800 | 566 | 800 | 355 | 800 | 600 | 800 |
Power [mW] | 34.8 | 8 | 40 | 2.57 | 0.51 | 35.4 | 39 | 0.0065 | 0.23 | 3.3 | 3.69 |
Area [mm] | 0.18 | 0.1 | 0.42 | 0.017 | – | 0.1557 | 0.11 | 0.07 | – | 0.026 | – |
FoM [dB] | 130.7 | 165 | 154 | 160.9 | 173.9 | 154.5 | 159.8 | 167.7 | 166.4 | 149.2 | 164.3 |
FoM [fJ/c-s] | 3256 | 43.2 | 500 | 42 | 14.9 | 153 | 201.2 | 26 | 14 | 235 | 32 |
Linearization | Inv. | Digital | Two-step | Digital | Digital | Digital | Resist. | Bulk- | Digital | Multiple | |
technique | Gauss. | calib. | loop | VCO-ADC | f-calib. | f-calib. | b-calib. | netw. | driven | f-calib | transc. |
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Alvero-Gonzalez, L.M.; Medina, V.; Kampus, V.; Paton, S.; Hernandez, L.; Gutierrez, E. Ring-Oscillator with Multiple Transconductors for Linear Analog-to-Digital Conversion. Electronics 2021, 10, 1408. https://doi.org/10.3390/electronics10121408
Alvero-Gonzalez LM, Medina V, Kampus V, Paton S, Hernandez L, Gutierrez E. Ring-Oscillator with Multiple Transconductors for Linear Analog-to-Digital Conversion. Electronics. 2021; 10(12):1408. https://doi.org/10.3390/electronics10121408
Chicago/Turabian StyleAlvero-Gonzalez, Leidy Mabel, Victor Medina, Vahur Kampus, Susana Paton, Luis Hernandez, and Eric Gutierrez. 2021. "Ring-Oscillator with Multiple Transconductors for Linear Analog-to-Digital Conversion" Electronics 10, no. 12: 1408. https://doi.org/10.3390/electronics10121408