One embodiment relates to a multiple-channel serializer circuit that includes a plurality of one-channel serializers. A one-channel serializer of the plurality of one-channel serializes includes a local 2× frequency clock generator with a non-divider structure. Other embodiments relate to methods of using a non-divider circuit to generate a local 2× frequency clock signal in a one-channel serializer of a multiple-channel serializer. Another embodiment relates to a local 2× frequency clock generator circuit with a non-divider structure. The local 2× frequency clock generator circuit includes a first circuit path which is selected by multiplexers for a first serialization ratio and may also include a second circuit path which is selected by the multiplexers for a second serialization ratio. Other embodiments and features are also disclosed.

A system, apparatus, and method for testing blocks of a system on a chip (SOC) are described herein. An SOC, in accordance with various embodiments, may include a serial communication interface configured to multiplex, serialize, and/or parallelize signals streams from selected blocks of the SOC to an off-chip test unit through an off-chip serial communication interface. Other embodiments may be described and claimed.

An example output driver includes a plurality of output circuits coupled in parallel between a first voltage supply node and a second voltage supply node. Each of the plurality of output circuits includes a differential input that is coupled to receive a logic signal of a plurality of logic signals and a differential output that is coupled to a common output node. The output driver further includes voltage regulator(s), coupled to the voltage supply node(s), and a current compensation circuit. The current compensation circuit includes a switch coupled in series with a current source, where the switch and the current source are coupled between the first voltage supply node and the second voltage supply node. An event detector is coupled to the switch to supply an enable signal and to control state of the enable signal based on presence of a pattern in the plurality of logic signals.

An example output driver includes a plurality of output circuits coupled in parallel between a first voltage supply node and a second voltage supply node. Each of the plurality of output circuits includes a differential input that is coupled to receive a logic signal of a plurality of logic signals and a differential output that is coupled to a common output node. The output driver further includes voltage regulator(s), coupled to the voltage supply node(s), and a current compensation circuit. The current compensation circuit includes a switch coupled in series with a current source, where the switch and the current source are coupled between the first voltage supply node and the second voltage supply node. An event detector is coupled to the switch to supply an enable signal and to control state of the enable signal based on presence of a pattern in the plurality of logic signals.

A communication apparatus includes a serializer configured to convert parallel data into serial data and output the serial data; and a deserializer configured to convert the serial data output from the serializer into parallel data and output the parallel data. The serializer is configured to add first data used for detecting unique data in the parallel data before the unique data, add second data used for detecting the unique data after the unique data, and add third data whose length is variable to each of the first data and the second data.

A communication apparatus includes a serializer configured to convert parallel data into serial data and output the serial data; and a deserializer configured to convert the serial data output from the serializer into parallel data and output the parallel data. The serializer is configured to add first data used for detecting unique data in the parallel data before the unique data, add second data used for detecting the unique data after the unique data, and add third data whose length is variable to each of the first data and the second data.

A voltage-mode transmitter includes a calibration circuit having a replica circuit. By adjusting a feedback voltage driving a gate of a replica transistor in the replica circuit so that an impedance of the replica circuit matches an impedance of a variable resistor, the calibration circuit calibrates an output impedance of a single slice driver.

A voltage-mode transmitter includes a calibration circuit having a replica circuit. By adjusting a feedback voltage driving a gate of a replica transistor in the replica circuit so that an impedance of the replica circuit matches an impedance of a variable resistor, the calibration circuit calibrates an output impedance of a single slice driver.

A digital communication interface includes a deserializer module, a gearbox module, and a parallel communication channel connecting the gearbox module to the deserializer module. The deserializer module has a fixed deserialization factor. The gearbox module has a temporal translation factor to change bit-length of words received through the parallel communication channel to bit-length suitable for a downstream data path.

A data acquisition device comprises an analog-to-digital converter (ADC) circuit configured to produce a digital value from an analog input signal. The ADC circuit includes a signal input, a mode input, a serial output, and logic circuitry. The logic circuitry is configured to shift bits of the digital value out the serial output and change an order of the bits shifted out the serial output according to the mode input.