Abstract:
Aspects of the invention provide a fast one level zero-current-state XOR gate. An embodiment of the invention provides a first pair of differentially configured transistors and a level shifting resistor coupled to the first pair of differentially configured transistors. The one level zero-current-state XOR gate may also include a second pair of differentially configured transistors. A core of the XOR gate may be coupled to outputs of the first and the second pairs of differentially configured transistors.
Abstract:
A method and apparatus for adaptively controlling a variable gain amplifier (VGA). The operation of the VGA is separated into a low gain mode and a high gain mode and the mode in which the VGA is currently operating in is adaptively sensed. A threshold voltage is compared to a control voltage of the VGA; if the VGA is currently operating in the low gain mode and the control voltage is higher than the threshold voltage, the VGA is switched from the low gain mode to the high gain mode; and if the VGA is currently operating in the high gain mode and the control voltage is lower than the threshold voltage, the VGA is switched from the high gain mode to the low gain mode.
Abstract:
An input processing circuit includes a first and second input transistors for receiving a differential pair of first and second input signals, respectively. At least one resistor is coupled between first terminals of the first and second input transistors. The input processing circuit includes a variable gain amplifier (VGA) circuit. At least one first transistor has a gate terminal, and is coupled between the first terminals of the first and second input transistors. At least one second transistor has a gate terminal, and is coupled between the first terminals of the first and second input transistors. A gate switch is coupled to the gate terminal of the at least one second transistor. The at least one first transistor and the at least one second transistor adjust a gain of the input processing circuit in response to a control voltage. The control voltage is applied to the gate terminal of the at least one first transistor, and the control voltage is applied to the gate terminal of the at least one second transistor through the gate switch.
Abstract:
Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C3MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C3MOS logic with low power conventional CMOS logic. The combined C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems. The C3MOS structure enables the use of a power supply voltage that may be larger than the voltage required by the CMOS fabrication process, further enhancing the performance of the circuit.
Abstract translation:用于实现超高速电路的各种电路技术使用以常规CMOS工艺技术制造的电流控制CMOS(C 3/4 MOS)逻辑。 包括逆变器/缓冲器,电平移位器,NAND,NOR,异或门,锁存器,触发器等的整个逻辑元件族都使用C 3 MOS技术实现。 通过将高速C“3”MOS逻辑与低功耗常规CMOS逻辑相结合,实现了每个电路应用的功耗和速度之间的最佳平衡。 组合的三极管/ CMOS逻辑允许诸如光纤通信系统中使用的高速收发器之类的电路的更大集成。 C 3 O 3 MOS结构能够使用可能大于CMOS制造工艺所需的电压的电源电压,进一步提高电路的性能。
Abstract:
A method and apparatus for adaptively controlling a variable gain amplifier (VGA). The operation of the VGA is separated into a low gain mode and a high gain mode and the mode in which the VGA is currently operating in is adaptively sensed. A threshold voltage is compared to a control voltage of the VGA; if the VGA is currently operating in the low gain mode and the control voltage is higher than the threshold voltage, the VGA is switched from the low gain mode to the high gain mode; and if the VGA is currently operating in the high gain mode and the control voltage is lower than the threshold voltage, the VGA is switched from the high gain mode to the low gain mode.
Abstract:
A method and apparatus for adaptively controlling a variable gain amplifier (VGA). The operation of the VGA is separated into a low gain mode and a high gain mode and the mode in which the VGA is currently operating in is adaptively sensed. A threshold voltage is compared to a control voltage of the VGA; if the VGA is currently operating in the low gain mode and the control voltage is higher than the threshold voltage, the VGA is switched from the low gain mode to the high gain mode; and if the VGA is currently operating in the high gain mode and the control voltage is lower than the threshold voltage, the VGA is switched from the high gain mode to the low gain mode.
Abstract:
The present invention provides a method for tuning output drivers to an operating frequency based on settings used to tune other devices within the device such as a VCO. First the VCO within a PLL and clock circuit is tuned to the desired operating frequency. This operating frequency then corresponds to a discrete tuning setting. The discrete setting that causes the VCO to function at the operating frequency are then transferred to scaled amplifiers within output drivers. These drivers are then tuned to the operating frequency with these settings. This process eliminates the need to individually tune each output driver to function properly at the operating frequency.
Abstract:
Aspects of the invention provide a fast one level zero-current-state XOR gate. An embodiment of the invention provides a first pair of differentially configured transistors and a level shifting resistor coupled to the first pair of differentially configured transistors. The one level zero-current-state XOR gate may also include a second pair of differentially configured transistors. A core of the XOR gate may be coupled to outputs of the first and the second pairs of differentially configured transistors.
Abstract:
Expansion of the bandwidth of a wideband CMOS data amplifier is accomplished using various combinations of shunt peaking, series peaking, and miller capacitance cancellation. These various combinations are employed in any of the amplifier input stage, in intermediate stages, or in the last stage.
Abstract:
A converter for converting a single-ended input V.sub.IN to a differential output signal V.sub.OUT through positive and negative output terminals is disclosed. The converter comprises a fully differential amplifier with one of its input terminals coupled to the single-ended input and its other input terminal coupled to a fixed voltage. The converter also has a first resistor ("R.sub.1 ") coupled between the single-ended input and the positive input terminal of the fully differential amplifier, a second resistor ("R.sub.2 ") coupled between the fixed voltage and the negative input terminal of the fully differential amplifier, a third resistor ("R.sub.3 ") coupled between the positive input terminal and the negative output terminal of the fully differential amplifier, and a fourth resistor ("R.sub.4 ") coupled between the negative input terminal and the positive output terminal, wherein the values of such resistors are governed by: ##EQU1## The same principles can be applied to differential-to-single-ended converters as well.