Low Voltage Differential Signaling (LVDS) has become a popular choice for high-speed serial links to conquer the bandwidth bottleneck of intra-chip data transmission. This paper presents the design and the implementat...Low Voltage Differential Signaling (LVDS) has become a popular choice for high-speed serial links to conquer the bandwidth bottleneck of intra-chip data transmission. This paper presents the design and the implementation of LVDS Input/Output (I/O) interface circuits in a standard 0.18 μm CMOS technology using thick gate oxide devices (3.3 V), fully compatible with LVDS standard. In the proposed transmitter, a novel Common-Mode FeedBack (CMFB)circuit is utilized to keep the common-mode output voltage stable over Process, supply Voltage and Temperature (PVT) variations. Because there are no area greedy resistors in the CMFB circuitry, the disadvantage of large die area in existing transmitter structures is avoided. To obtain sufficient gain, the receiver consists of three am- plifying stages: a voltage amplifying stage, a transconductance amplifying stage, and a transimpedance amplifying stage. And to exclude inner nodes with high RC time constant, shunt-shunt negative feedback is introduced in the receiver. A novel active inductor shunt peaking structure is used in the receiver to fulfill the stringent requirements of high speed and wide Common-Mode Input Region (CMIR) without voltage gain, power dissipation and silicon area penalty. Simulation results show that data rates of 2 Gbps and 2.5 Gbps are achieved for the transmitter and receiver with power con- sumption of 13.2 mW and 8.3 mW respectively.展开更多
This research describes an integrated multi-channel high accuracy current control LED （light emitting diode） driver with low dropout regulator implemented in a 0.35μm TSMC 2P4M CMOS process. With the new trend of b...This research describes an integrated multi-channel high accuracy current control LED （light emitting diode） driver with low dropout regulator implemented in a 0.35μm TSMC 2P4M CMOS process. With the new trend of backlighting applications for mobile electronics and portable devices requiring a smaller size, lower cost, lesser noise and accurate current control LED driver, it came up with the idea of integrating more than one design features within a single chip. The analysis of using a capacitor-less low dropout regulator to power the constant current source has been explored, with the implementation of wide range battery voltage of 3 V to 5 V. Possible load current variations were introduced and verified to output a fixed voltage of 2.8 V. A regulated cascode current mirror structure forms the multi-channel configuration string of LED＇s; the design ensures a current matching of less than 1% error and achieves a high accuracy current control of less than 1% error, regardless of the LED＇s forward voltage variation. Moreover, for high end portable device with multimedia applications, dimming frequency can be set to 10 MHz. In addition, a switching output is a better approach for managing LED＇s contrast and brightness adjustment as well as maximizing power consumption, ensuring longer life for driving string of LEDs.展开更多
This paper presents an integrated power management unit （PMU） for a battery-operated wireless endoscopic system. This PMU is integrated with a baseband chip in standard 0.18μm CMOS technology,promising low cost, ea...This paper presents an integrated power management unit （PMU） for a battery-operated wireless endoscopic system. This PMU is integrated with a baseband chip in standard 0.18μm CMOS technology,promising low cost, ease in PCB design, and a minimum in system size. The optimized power supply architecture is derived from comparison. Circuits of sub blocks are presented in detail. As a result, only five small off-chip capacitances are required by PMU with an overall quiet current consumption of less than 100μA. Moreover,a digital calibration method is adopted to alleviate the effect of process variation. The achieved performance is also demonstrated with corresponding measurement results.展开更多
文摘Low Voltage Differential Signaling (LVDS) has become a popular choice for high-speed serial links to conquer the bandwidth bottleneck of intra-chip data transmission. This paper presents the design and the implementation of LVDS Input/Output (I/O) interface circuits in a standard 0.18 μm CMOS technology using thick gate oxide devices (3.3 V), fully compatible with LVDS standard. In the proposed transmitter, a novel Common-Mode FeedBack (CMFB)circuit is utilized to keep the common-mode output voltage stable over Process, supply Voltage and Temperature (PVT) variations. Because there are no area greedy resistors in the CMFB circuitry, the disadvantage of large die area in existing transmitter structures is avoided. To obtain sufficient gain, the receiver consists of three am- plifying stages: a voltage amplifying stage, a transconductance amplifying stage, and a transimpedance amplifying stage. And to exclude inner nodes with high RC time constant, shunt-shunt negative feedback is introduced in the receiver. A novel active inductor shunt peaking structure is used in the receiver to fulfill the stringent requirements of high speed and wide Common-Mode Input Region (CMIR) without voltage gain, power dissipation and silicon area penalty. Simulation results show that data rates of 2 Gbps and 2.5 Gbps are achieved for the transmitter and receiver with power con- sumption of 13.2 mW and 8.3 mW respectively.
文摘This research describes an integrated multi-channel high accuracy current control LED （light emitting diode） driver with low dropout regulator implemented in a 0.35μm TSMC 2P4M CMOS process. With the new trend of backlighting applications for mobile electronics and portable devices requiring a smaller size, lower cost, lesser noise and accurate current control LED driver, it came up with the idea of integrating more than one design features within a single chip. The analysis of using a capacitor-less low dropout regulator to power the constant current source has been explored, with the implementation of wide range battery voltage of 3 V to 5 V. Possible load current variations were introduced and verified to output a fixed voltage of 2.8 V. A regulated cascode current mirror structure forms the multi-channel configuration string of LED＇s; the design ensures a current matching of less than 1% error and achieves a high accuracy current control of less than 1% error, regardless of the LED＇s forward voltage variation. Moreover, for high end portable device with multimedia applications, dimming frequency can be set to 10 MHz. In addition, a switching output is a better approach for managing LED＇s contrast and brightness adjustment as well as maximizing power consumption, ensuring longer life for driving string of LEDs.
基金the National Natural Science Foundation of China(No.60475018)~~
文摘This paper presents an integrated power management unit （PMU） for a battery-operated wireless endoscopic system. This PMU is integrated with a baseband chip in standard 0.18μm CMOS technology,promising low cost, ease in PCB design, and a minimum in system size. The optimized power supply architecture is derived from comparison. Circuits of sub blocks are presented in detail. As a result, only five small off-chip capacitances are required by PMU with an overall quiet current consumption of less than 100μA. Moreover,a digital calibration method is adopted to alleviate the effect of process variation. The achieved performance is also demonstrated with corresponding measurement results.
