250ms
Maxim
indicates the 250ms maximum busy length.
Design DocumentRaw Githubusercontent
SD Specifications Part 1 Physical Layer Simplified Specification Version 8.00
Simplified physical layer specification for SD cards version 8.00, covering SDHC, SDXC, SDUC, UHS-I/II, and SD Express interfaces including PCIe 4.0 dual-lane support.
Overview
This document outlines the Physical Layer Simplified Specification Version 8.00 as defined by the SD Card Association. It provides technical requirements for SD memory card systems, including capacity classifications such as SDHC, SDXC, and SDUC (up to 128TB). The specification details multiple bus protocols and interfaces: legacy SD bus, SPI, UHS-I, UHS-II, and SD Express (PCIe/NVMe). Version 8.00 specifically adds support for Full Size SD Express cards utilizing PCIe 4.0 single and dual lanes, as well as PCIe 3.1 dual lanes. It includes pin assignments, power limit information, speed class ratings (including Video Speed Class and Application Performance Class), and bus timing requirements for hardware developers and host implementers.
Use Cases
- Development of SD card host controllers and interfaces
- Implementation of PCIe and NVMe protocols in SD Express card designs
- Hardware design for UHS-I and UHS-II high-speed memory interfaces
- Validation of SD card mechanical and electrical compatibility
- Design of memory storage solutions for mobile and video applications
Topics
SD Card Association
Physical Layer Specification
SD Express
PCIe 4.0
NVMe
SDUC
UHS-II
UHS-I
Bus Protocol
SDHC
SDXC
Pin Assignment
Referenced Parts
| 250ms | Maxim | indicates the 250ms maximum busy length. |