University of California

Sheau Jiung Lee

Mau-Chung Frank Chang

Yanghyo Kim

Wei-Han Cho

Yilei Li

Gabriel L Virbila

A chip-to-chip communications circuit which is particularly well-suited for short range communication (less than a few inches) from one integrated circuit (chip) to another is presented. The circuits preferably utilize multi-frequency quadrature amplitude modulation (QAM) mechanisms for converting digital data bits from a parallel form into a serial analog stream for communication over a chip I/O connection. Differential current mode modulation in the transmitter, and demodulation in the receiver, are utilized which reduce latency and power-consumption while increasing manufacturing yields and resilience to process variations.

Differential current mode low latency modulation and demodulation for chip-to-chip connection

A chip-to-chip communications circuit which is particularly well-suited for short range wired RF communication from one integrated circuit (chip) to another is presented. The circuits preferably utilize multi-frequency quadrature amplitude modulation (QAM) mechanisms for converting digital data bits from a parallel form into a serial analog stream for communication over a chip I/O connection. During a phase calibration cycle, a phase adjustment controller in the transmitter interoperates with a phase adjustment controller in the receiver, to adjust a phase locked-loop (PLL) circuit to correct for the phase delay arising in response to signal propagation between transmitter and receiver.

Phase synchronization of modulation or demodulation for QAM-based multiband TSV-link

A serializer and de-serializer circuit having self tracking circuitry which is particularly well-suited for use in communicating digital data from one integrated circuit (chip) to another for implementing chip-to-chip communications is presented. The circuits are scalable and utilize a multi-frequency modulation mechanism (e.g., QAM) for converting digital data bits into a serial analog stream at multiple frequencies for communication over a chip I/O connection. The track pulse generated on the transmitter side is serialized through the same path as the data, and demodulated through the same path in the de-serializer to provide synchronization with the data, without the need for complicated base band processing.

Self track scheme for multi frequency band serializer de-serializer I/O circuits

A serializer and de-serializer circuit which is particularly well-suited for use in communicating digital data from one integrated circuit (chip) to another for implementing chip-to-chip communications is presented. The circuits are scalable and utilize a multi-frequency quadrature amplitude modulation (QAM) mechanism for converting digital data bits from a parallel form into a serial analog stream for communication over a chip I/O connection. The serializer has multiple digital-to-analog converters (DACs) whose outputs are directed to QAM mixer inputs, within QAMs at multiple frequencies, whose outputs are summed into a single analog signal for communication over an I/O connection. The de-serializer amplifies the analog signal which is received by QAM mixers at different frequencies, whose outputs are low pass filtered and converted back to parallel digital data bits.

Scalable serial/de-serial I/O for chip-to-chip connection based on multi-frequency QAM scheme

A voltage controlled oscillator (VCO) which can be configured with a smaller tuning range than is ordinarily required is presented. Ordinarily, the tuning range is selected much broader than the application warrants so that sufficient range is still provided despite VCO process variations. The inventive VCO is able to substantially eliminate the effects of process variation by utilizing a calibration circuit and process, so that variation in VCO device operation is minimized despite substantial process variation. Accordingly, the inventive VCO device is subject to reduced levels of jitter as its range need not be utilized for overcoming process variation arising during device fabrication.

Growing community of inventors

Saratoga, CA, United States of America

Sheau Jiung Lee