Semiconductor package on package memory channels with arbitration for shared calibration resources

摘要

A package on package (PoP) apparatus includes a shared ZQ calibration path and a shared ZQ calibration resistor for calibrating multiple channels of DRAM on a memory package of the PoP apparatus. Arbitration circuitry on a processor package of the PoP apparatus is coupled to separate memory controllers for the multiple memory channels. The arbitration circuitry is configured to indicate availability of the shared ZQ calibration resistor. The memory controllers are configured to communicate with the arbitration circuitry before performing a ZQ calibration and to delay the ZQ calibration when the arbitration circuitry indicates the ZQ calibration resistor is busy.

主权项

1. A semiconductor package on package (PoP) apparatus, comprising:
a first package including a first memory controller and a second memory controller; a second package coupled to the first package, the second package including a first system memory channel and a second system memory channel; a calibration resistor coupled to the first system memory channel and the second system memory channel via a conductive path through the first package; and arbitration circuitry on the first package coupled to the first memory controller and the second memory controller, the arbitration circuitry configured to prevent calibration signals of the first memory controller from overlapping with the calibration signals of the second memory controller.