Rambus Inc.

Eugene C Ho

Frederick Abbott Ware

Huy M Nguyen

Kyung Suk Oh

Woopoung Kim

Benedict C Lau

Bret G Stott

Chanh Vi Tran

John Welsford Brooks

Philip Yeung

Julia V M Cline

Embodiments of a memory controller are described. This memory controller communicates signals to a memory device via a signal line, which can be a data signal line or a command/address signal line. Termination of the signal line is divided between an external impedance outside of the memory controller and an internal impedance within the memory controller. The memory controller does not activate the external impedance prior to communicating the signals and, therefore, does not deactivate the external impedance after communicating the signals. The internal impedance of the memory controller can be enabled or disabled in order to reduce interface power consumption. Moreover, the internal impedance may be implemented using a passive component, an active component or both. For example, the internal impedance may include either or both an on-die termination and at least one driver.

Signal lines with internal and external termination

An integrated circuit is described. The integrated circuit includes an interface circuit that includes a transmitter and a receiver. A generator in the integrated circuit is selectively coupled to the transmitter. The generator is to provide a test sequence that is output by the transmitter during a test mode of operation. A memory in the integrated circuit is selectively coupled to the generator and the receiver. The memory is to receive and synchronize the test sequence and a signal corresponding to the test sequence that is received by the receiver. A logic circuit in the integrated circuit is to compare the test sequence and the signal.

Self-test method for interface circuit

Interface test circuit

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Saratoga, CA, United States of America

Eugene C Ho