A new low voltage swing gate driver for integrated buck converter with synchronous rectifier

This paper attempts to disclose a new GaN-based device, called the P-Cascode GaN HEMT, which uses only a single gate driver to control both the D-mode GaN and PMOS transistors. The merit of this synchronous buck converter is that it can reduce the circuit complexity of the synchronous buck converter, which is widely used to provide non-isolated power for low-voltage and high-current supply to system chips; therefore, the power conversion efficiency of the converter can be improved. In addition, the high side switch using a single D-mode GaN HEMT, which has no body diode, can prevent the bi-directional flow and thus reduce the power loss and cost compared to a design based on a series of two opposite MOSFETs. The experiment shows that the proposed P-Cascode GaN HEMT efficiency is above 98% when it operates at 500 kHz with 6 W output. With the input voltage at 12 V, the synchronous buck converter provides an adjustable regulated output voltage from 1.2 V to 10 V while delivering a maximum output current of 2 A.

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A 10 MHz GaN Driver IC with Bang-Bang DeadTime Control for Synchronous Rectifier Buck Converter

2020 IEEE Energy Conversion Congress and Exposition (ECCE) ◽

10.1109/ecce44975.2020.9236280 ◽

2020 ◽

Author(s):

Pin Ying Wang ◽

Ping Kun Chiu ◽

Sheng Teng Li ◽

Ching Jan Chen ◽

Chih Chao Hsu

Keyword(s):

Buck Converter ◽

Synchronous Rectifier

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Starter for Voltage Boost Converter to Harvest Thermoelectric Energy for Body-Worn Sensors

Energies ◽

10.3390/en14144092 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4092

Author(s):

Grzegorz Blakiewicz ◽

Jacek Jakusz ◽

Waldemar Jendernalik

Keyword(s):

Threshold Voltage ◽

Low Voltage ◽

Boost Converter ◽

Mos Transistors ◽

Weak Inversion ◽

Thermoelectric Energy ◽

On Chip ◽

Voltage Swing ◽

High Output Voltage ◽

High Output

This paper examines the suitability of selected configurations of ultra-low voltage (ULV) oscillators as starters for a voltage boost converter to harvest energy from a thermoelectric generator (TEG). Important properties of particularly promising configurations, suitable for on-chip implementation are compared. On this basis, an improved oscillator with a low startup voltage and a high output voltage swing is proposed. The applicability of n-channel native MOS transistors with negative or near-zero threshold voltage in ULV oscillators is analyzed. The results demonstrate that a near-zero threshold voltage transistor operating in the weak inversion region is most advantageous for the considered application. The obtained results were used as a reference for design of a boost converter starter intended for integration in 180-nm CMOS X-FAB technology. In the selected technology, the most suitable transistor available with a negative threshold voltage was used. Despite using a transistor with a negative threshold voltage, a low startup voltage of 29 mV, a power consumption of 70 µW, and power conversion efficiency of about 1.5% were achieved. A great advantage of the proposed starter is that it eliminates a multistage charge pump necessary to obtain a voltage of sufficient value to supply the boost converter control circuit.

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