Abstract: Embodiments of the invention are directed to a single driver that can be used to transmit data with configurable levels of pre-emphasis, and can have either a constant or adjustable driver output impendence, selectively. One embodiment, directed to a driver apparatus, is associated with a digital communication channel for transmitting data signals, wherein at least one of the signals includes a higher frequency component. The apparatus comprises a first sub-driver that has a constant output impedance, and is selectively configurable to implement two or more different levels of pre-emphasis. The apparatus further comprises one or more second sub-drivers.

Abstract: A system includes a first CML buffer configured to receive a first bias signal and a first CML signal of a first CML logic family. The first CML buffer produces a second CML signal of the first CML logic family based on the first CML signal and the first bias signal. A first coupling capacitor module couples to the first CML buffer. The first coupling capacitor module receives the second CML signal and produces a third CML signal based on the second CML signal. A second CML buffer couples to the coupling capacitor module and receives a second bias signal and the third CML signal, producing a fourth CML signal of a second CML logic family. A feedback module couples to the second CML buffer and receives the fourth CML signal producing a fifth CML signal. The second CML buffer is produces the fourth CML signal based on the second bias signal, the third CML signal, and the fifth CML signal.

Abstract: Embodiments of the invention are directed to a single driver that can be used to transmit data with configurable levels of pre-emphasis, and can have either a constant or adjustable driver output impendence, selectively. One embodiment, directed to a driver apparatus, is associated with a digital communication channel for transmitting data signals, wherein at least one of the signals includes a higher frequency component. The apparatus comprises a first sub-driver that has a constant output impedance, and is selectively configurable to implement two or more different levels of pre-emphasis. The apparatus further comprises one or more second sub-drivers.

Abstract: A system includes a first CML buffer configured to receive a first bias signal and a first CML signal of a first CML logic family. The first CML buffer produces a second CML signal of the first CML logic family based on the first CML signal and the first bias signal. A first coupling capacitor module couples to the first CML buffer. The first coupling capacitor module receives the second CML signal and produces a third CML signal based on the second CML signal. A second CML buffer couples to the coupling capacitor module and receives a second bias signal and the third CML signal, producing a fourth CML signal of a second CML logic family. A feedback module couples to the second CML buffer and receives the fourth CML signal producing a fifth CML signal. The second CML buffer is produces the fourth CML signal based on the second bias signal, the third CML signal, and the fifth CML signal.

Abstract: A first clock signal of frequency F is used to couple data to an off-chip driver (OCD) using a master/slave flip flop (FF), wherein the master latch is clocked with the first clock signal and the slave latch is clocked with the complement of the first clock signal. A second clock signal of frequency F/2 is generated from the first clock signal. The second clock signal is shifted a time equal to substantially one-half the cycle of the first clock signal. In one embodiment, the second clock is shifted using a delay line circuit. In another embodiment, the second clock is shifted using a master/slave FF, wherein the master latch is clocked with the complement of the first clock signal and the slave latch is clocked with the first clock signal. The logic state transitions of the data between edges of the propagating clock thereby reducing coupling to the clock transitions and thus reducing edge jitter.

Abstract: A protection circuit with a positive field effect transistor coupled to a power source, a negative field effect transistor connected to a pass-gate and a circuit ground, a circuit input terminal, a multi-level source of protection voltage coupled to an external circuit and at least three additional field effect transistors. A drain of the negative field effect transistor couples to a gate of the positive field effect transistor. When the circuit input terminal is low the pass-gate is on; when the circuit input terminal is high the pass-gate is off. Embodiments of the invention also include stacks of three or more field effect transistors.

Abstract: A first clock signal of frequency F is used to couple data to an off-chip driver (OCD) using a master/slave flip flop (FF), wherein the master latch is clocked with the first clock signal and the slave latch is clocked with the complement of the first clock signal. A second clock signal of frequency F/2 is generated from the first clock signal. The second clock signal is shifted a time equal to substantially one-half the cycle of the first clock signal. In one embodiment, the second clock is shifted using a delay line circuit. In another embodiment, the second clock is shifted using a master/slave FF, wherein the master latch is clocked with the complement of the first clock signal and the slave latch is clocked with the first clock signal. The logic state transitions of the data between edges of the propagating clock thereby reducing coupling to the clock transitions and thus reducing edge jitter.

Abstract: A first clock signal of frequency F is used to couple data to an off-chip driver (OCD) using a master/slave flip flop (FF), wherein the master latch is clocked with the first clock signal and the slave latch is clocked with the complement of the first clock signal. A second clock signal of frequency F/2 is generated from the first clock signal. The second clock signal is shifted a time equal to substantially one-half the cycle of the first clock signal. In one embodiment, the second clock is shifted using a delay line circuit. In another embodiment, the second clock is shifted using a master/slave FF, wherein the master latch is clocked with the complement of the first clock signal and the slave latch is clocked with the first clock signal. The logic state transitions of the data between edges of the propagating clock thereby reducing coupling to the clock transitions and thus reducing edge jitter.

Abstract: A protection circuit with a positive field effect transistor coupled to a power source, a negative field effect transistor connected to a pass-gate and a circuit ground, a circuit input terminal, a multi-level source of protection voltage coupled to an external circuit and at least three additional field effect transistors. A drain of the negative field effect transistor couples to a gate of the positive field effect transistor. When the circuit input terminal is low the pass-gate is on; when the circuit input terminal is high the pass-gate is off. Embodiments of the invention also include stacks of three or more field effect transistors.

Abstract: A first clock signal of frequency F is used to couple data to an off-chip driver (OCD) using a master/slave flip flop (FF), wherein the master latch is clocked with the first clock signal and the slave latch is clocked with the complement of the first clock signal. A second clock signal of frequency F/2 is generated from the first clock signal. The second clock signal is shifted a time equal to substantially one-half the cycle of the first clock signal. In one embodiment, the second clock is shifted using a delay line circuit. In another embodiment, the second clock is shifted using a master/slave FF, wherein the master latch is clocked with the complement of the first clock signal and the slave latch is clocked with the first clock signal. The logic state transitions of the data between edges of the propagating clock thereby reducing coupling to the clock transitions and thus reducing edge jitter.

Abstract: A line driver for off-chip communication comprises multiple parallel stages each with separate inputs. The parallel stages each have a controlled impedance when driving the line driver output node to a logic zero or a logic one. A line driver controller is used to select what combination of driver stages are used to drive the output node based on whether the output node is transitioning between logic state or is remaining static. During power-up, a test program tries different combinations of driver stages for particular symbol patterns and determines what is the optimal ratio between line driver resistance for the dynamic and static cases and stores the optimum combination. The data stream feeding the line driver is sampled in real time to determine the transition states and selects the optimal number of driver stages for each case.