Western Digital Technologies, Inc.

Sayed Mobin

John Thomas Contreras

Rehan Ahmed Zakai

Srinivas Rajendra

Gokul Kumar

Pranav Balachander

Daniel Oh

David Zhang

The present disclosure generally relates to apparatuses and methods for transmission line termination. In one embodiment an apparatus includes a stack of uniform memory dies and a storage controller. Each uniform memory die in the stack of uniform memory dies couples to a transmission line in series through wire bonds to form a transmission path. Each memory die includes an on-die termination resistance circuit connected to the transmission line. The on-die termination resistance circuit provides a minimum termination resistance. The storage controller addresses a target uniform memory die of the stack of uniform memory dies for an operation. The storage controller enables the on-die termination resistance circuits of a plurality of uniform memory dies along the transmission path. The storage controller transmits a data signal for the operation to the target uniform memory die with the on-die termination resistance circuit enabled for the plurality of uniform memory dies.

Distributed grouped terminations for multiple memory integrated circuit systems

A circuit interconnect for high bandwidth and high die-count memory stacks. The circuit interconnect may include a first ground trace, a first signal trace, a second ground trace, and a second signal trace. The first ground trace may reside in a first layer of a multilayer printed circuit board. The first signal trace may be positioned adjacent to the first ground trace within the first layer. The second ground trace may reside within a second layer of the multilayer printed circuit board. The second signal trace may be positioned adjacent to the second ground trace within the second layer.

Printed circuit board compensation structure for high bandwidth and high die-count memory stacks

An apparatus may include a controller die and a group of dies that communicate with each other via a transmission line. The transmission line includes a first portion integrated with a printed circuit board, and a second portion that includes a plurality of wire bonds bonded to input/output pads of the group of dies. The transmission line further includes a resistor circuit connected in series with the first portion and the second portion. The resistor circuit has a resistance value that provides reduced reflection coefficients over the transmission line between the first portion and the second portion. An on-die termination resistor circuit on the controller side is removed, with the inclusion of the resistor circuit.

Series resistance in transmission lines for die-to-die communication

An apparatus includes a controller die and a group of dies that communicate with each other via a transmission line. Less than all of the dies of the group includes a respective on-die termination resistance circuit coupled to the transmission line. In some embodiments, one of the dies that includes an on-die termination resistance circuit is an end die of the group. In particular embodiments, the end die is the only die of the group that includes an on-die termination resistance circuit coupled to the transmission line. Transmission frequencies or data rates may be increased without degrading signal quality by removing capacitance associated with on-die termination resistance circuits from at least one of the dies of the group.

Dedicated termination dies for memory systems

An active low-power termination circuit includes a first leg of a pair of transistors connected in series between the high supply level and ground, where the termination input is at a node between the transistors of the first node. A second leg uses a feed forward mechanism to control the voltage levels on the control gates of the transistors of the first leg. The second leg includes a second pair diode connected transistors, each of which is has its control gate connected to the control gate of the corresponding transistor in the first leg. A variable current source connected in series with the transistors of the second leg and is controlled by the output of a difference amplifier that has one input connect to an intermediate node of the second leg and a second input connected to a reference level intermediate to the high supply level and ground.

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San Jose, CA, United States of America

Sayed Mobin