QUALCOMM Incorporated
OPEN-LOOP, SUPER FAST, HALF-RATE CLOCK AND DATA RECOVERY FOR NEXT GENERATION C-PHY INTERFACES

Abstract:

Methods, apparatus, and systems for communication over a multi-wire, multi-phase interface are disclosed. A clock recovery apparatus has a plurality of pulse generating circuits, a logic circuit and a delay flipflop. Each pulse generating circuit generates transition pulses in response to transitions in one of three difference signals representative of a difference in signaling state of a pair of wires in a three-wire bus. Transitions in the difference signals can occur at boundaries between sequentially-transmitted symbols. The first logic circuit may provide a single pulse in a combination signal at each boundary between pairs of symbols by combining one or more transition pulses. The delay flipflop is configured to respond to each pulse in the combination signal by changing signaling state of a clock signal that is output by the clock recovery apparatus. The symbols may be sequentially transmitted over the three-wire bus in accordance with a C-PHY protocol.