This paper describes the design and analysis of a fully differential,gain-enhanced CMOS telescopic operational transconductance amplifier （OTA） used in a pipeline analog-to-digital converter （ADC）. Specifications ...This paper describes the design and analysis of a fully differential,gain-enhanced CMOS telescopic operational transconductance amplifier （OTA） used in a pipeline analog-to-digital converter （ADC）. Specifications of the OTA are derived from the requirements of ADC. Simulation shows that for a lpF load capacitance, this OTA achieves a high DC gain （approximately 145dB） and a wide unity-gain bandwidth （above 750MHz） at a phase margin 58°. In a configuration where the closed loop-gain is 4,the design spends about 18ns for settling with 0.05% accuracy. Simulations of this design are performed in SMIC CMOS 0.18μm technology.展开更多
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
文摘This paper describes the design and analysis of a fully differential,gain-enhanced CMOS telescopic operational transconductance amplifier （OTA） used in a pipeline analog-to-digital converter （ADC）. Specifications of the OTA are derived from the requirements of ADC. Simulation shows that for a lpF load capacitance, this OTA achieves a high DC gain （approximately 145dB） and a wide unity-gain bandwidth （above 750MHz） at a phase margin 58°. In a configuration where the closed loop-gain is 4,the design spends about 18ns for settling with 0.05% accuracy. Simulations of this design are performed in SMIC CMOS 0.18μm technology.
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.
