Dual-bank memory module with stacked DRAM chips having a concave-shaped re-route PCB in-between
US6542393B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 2002 |
| Grant date | Apr 1, 2003 |
| Priority date | — |
| Expiry date | Apr 24, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/10689
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A memory module has memory chips in stacks. The lower memory chip in a stack has pins that are soldered to pads on the module substrate. A hollowed printed-circuit board (PCB) has a hollow opening on the bottom with about the same width, length, and depth as the top cap of the lower memory chip. The hollowed PCB fits over the top cap of the lower memory chip and has lower pads on its lower surface but outside of the hollow opening. The lower pads are soldered to the top shoulders of the pins of the lower memory chip. An upper memory chip has pins that are soldered to pads on the upper surface of the hollowed PCB. The hollowed PCB has a metal trace that re-routes a second bank-select signal from a no-connect pin of the lower memory chip to a bank-select pin of the upper memory chip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.