The short-distance low-power technologies for wireless access communications, including Bluetooth, Ultra-Wideband (UWB) and Wireless Fidelity (Wi-Fi), focus on the physical layer and Medium Access Control (MAC) layer....The short-distance low-power technologies for wireless access communications, including Bluetooth, Ultra-Wideband (UWB) and Wireless Fidelity (Wi-Fi), focus on the physical layer and Medium Access Control (MAC) layer. Bluetooth is a wireless protocol for exchanging data over short distances. It is an alternative to RS232 data cables. UWB is a radio technology that can be used at very low energy levels for short range. It provides flexible high-bandwidth wireless access. Wi-Fi enables the wireless connection of fast-access devices and mobile devices in Wireless Local Access Network (WLAN) and it is suitable for long distances. The standardizations of the above technologies have been developed and published soon after the emergence of these technologies. Among all the standards, Bluetooth and Wi-Fi are the most important ones.展开更多
This paper proposes a low-power MOS current mode logic （MCML） circuit with sleep-transistor to reduce the leakage current. The sleep-transistor is used to high-threshold voltage transistor to minimize the leakage cu...This paper proposes a low-power MOS current mode logic （MCML） circuit with sleep-transistor to reduce the leakage current. The sleep-transistor is used to high-threshold voltage transistor to minimize the leakage current. The 16× 16 bit parallel multiplier is designed with the proposed technology. Comparing with the previous MCML circuit, the circuit achieves the reduction of the power consumption in sleep mode by 1/258. This circuit is designed with Samsung 0.35 um complementary metal oxide semiconductor （CMOS） process. The validity and effectiveness are verified through the HSPICE simulation.展开更多
This paper presents a novel dual-mode step-up （boost） DC/DC converter. Pulse-frequency modulation （PFM） is used to improve the efficiency at light load. This converter can operate between pulse-width modulation （...This paper presents a novel dual-mode step-up （boost） DC/DC converter. Pulse-frequency modulation （PFM） is used to improve the efficiency at light load. This converter can operate between pulse-width modulation （PWM） and pulse-frequency modulation. The converter will operate in PFM mode at light load and in PWM mode at heavy load. The maximum conversion efficiency of this converter is 96%. The conversion efficiency is greatly improved when load current is below 100 mA. Additionally, a soft-start circuit and a variable-sawtooth frequency circuit are proposed in this paper. The former is used to avoid the large switching current at the start up of the converter and the latter is utilized to reduce the EMI of the converter.展开更多
Increasingly, mobile communications standards require high power efficiency and low currents in the low power mode. This paper proposes a fully-integrated multi-mode and multi-band power amplifier module （PAM） to me...Increasingly, mobile communications standards require high power efficiency and low currents in the low power mode. This paper proposes a fully-integrated multi-mode and multi-band power amplifier module （PAM） to meet these requirements. A dual-path PAM is designed for high-power mode （HPM）, medium-power mode （MPM）, and low-power mode （LPM） operations without any series switches for different mode selection. Good performance and significant current saving can be achieved by using an optimized load impedance design for each power mode. The PAM is tapeout with the InGaP/GaAs heterojunction bipolar transistor （HBT） process and the 0.18-μm complementary metal-oxide semiconductor （CMOS） process. The test results show that the PAM achieves a very low quiescent current of 3 mA in LPM. Meanwhile, across the 1.7-2.0 GHz frequency, the PAM performs well. In HPM, the output power is 28 dBm with at least 39.4% PAE and 240 dBc adjacent channel leakage ratio 1 （ACLR1）. In MPM, the output power is 17 dBm, with at least 21.3% PAE and -43 dBc ACLR1. In LPM, the output power is 8 dBm, with at least 18.2% PAE and -40 dBc ACLR1.展开更多
文摘The short-distance low-power technologies for wireless access communications, including Bluetooth, Ultra-Wideband (UWB) and Wireless Fidelity (Wi-Fi), focus on the physical layer and Medium Access Control (MAC) layer. Bluetooth is a wireless protocol for exchanging data over short distances. It is an alternative to RS232 data cables. UWB is a radio technology that can be used at very low energy levels for short range. It provides flexible high-bandwidth wireless access. Wi-Fi enables the wireless connection of fast-access devices and mobile devices in Wireless Local Access Network (WLAN) and it is suitable for long distances. The standardizations of the above technologies have been developed and published soon after the emergence of these technologies. Among all the standards, Bluetooth and Wi-Fi are the most important ones.
文摘This paper proposes a low-power MOS current mode logic （MCML） circuit with sleep-transistor to reduce the leakage current. The sleep-transistor is used to high-threshold voltage transistor to minimize the leakage current. The 16× 16 bit parallel multiplier is designed with the proposed technology. Comparing with the previous MCML circuit, the circuit achieves the reduction of the power consumption in sleep mode by 1/258. This circuit is designed with Samsung 0.35 um complementary metal oxide semiconductor （CMOS） process. The validity and effectiveness are verified through the HSPICE simulation.
基金the National Science Council of Taiwan, China, under Grant No. NSC 95-2221-E-305010.
文摘This paper presents a novel dual-mode step-up （boost） DC/DC converter. Pulse-frequency modulation （PFM） is used to improve the efficiency at light load. This converter can operate between pulse-width modulation （PWM） and pulse-frequency modulation. The converter will operate in PFM mode at light load and in PWM mode at heavy load. The maximum conversion efficiency of this converter is 96%. The conversion efficiency is greatly improved when load current is below 100 mA. Additionally, a soft-start circuit and a variable-sawtooth frequency circuit are proposed in this paper. The former is used to avoid the large switching current at the start up of the converter and the latter is utilized to reduce the EMI of the converter.
基金Project supported by the National Natural Science Foundation of China(No.61201244)
文摘Increasingly, mobile communications standards require high power efficiency and low currents in the low power mode. This paper proposes a fully-integrated multi-mode and multi-band power amplifier module （PAM） to meet these requirements. A dual-path PAM is designed for high-power mode （HPM）, medium-power mode （MPM）, and low-power mode （LPM） operations without any series switches for different mode selection. Good performance and significant current saving can be achieved by using an optimized load impedance design for each power mode. The PAM is tapeout with the InGaP/GaAs heterojunction bipolar transistor （HBT） process and the 0.18-μm complementary metal-oxide semiconductor （CMOS） process. The test results show that the PAM achieves a very low quiescent current of 3 mA in LPM. Meanwhile, across the 1.7-2.0 GHz frequency, the PAM performs well. In HPM, the output power is 28 dBm with at least 39.4% PAE and 240 dBc adjacent channel leakage ratio 1 （ACLR1）. In MPM, the output power is 17 dBm, with at least 21.3% PAE and -43 dBc ACLR1. In LPM, the output power is 8 dBm, with at least 18.2% PAE and -40 dBc ACLR1.
