JEDEC Standard No. 84-A43
Page 3
4 General description
The MultiMediaCard is an universal low cost data storage and communication media. It is designed to
cover a wide area of applications as smart phones, cameras, organizers, PDAs, digital recorders, MP3 play-
ers, pagers, electronic toys, etc. Targeted features are high mobility and high performance at a low cost
price. These features include low power consumption and high data throughput at the memory card inter-
face.
The MultiMediaCard communication is based on an advanced 13-pin bus. The communication protocol is
defined as a part of this standard and referred to as the MultiMediaCard mode.
To provide for the forecasted migration of CMOS power (V
DD
) requirements and for compatibility and
integrity of MultiMediaCard systems, two types of MultiMediaCards are defined in this standard specifica-
tion, which differ only in the valid range of system V
DD
. These two card types are referred to as High Volt-
age MultiMediaCard and Dual Voltage MultiMediaCard.
The purpose of the system specification is the definition of the MultiMediaCard, its environment and han-
dling. It gives guidelines for a system designer. The system specification also defines a tool box (a set of
macro functions and algorithms) which contributes to reducing the design-in costs.
The document is split up into several portions. The MultimediaCard Features are described in Section 5.
Section 6 gives a general overview of the system components: card, bus, and host.
The common MultiMediaCard characteristics are described in Section 7. As this description defines an
overall set of card properties, you should work with the vendor-specific, product documentation in parallel.
Section 8 describes the card registers.
The SPI mode is removed from this standard.
All error protection techniques employed in this standard are described in Section 10.
Section 11 describes the physical and mechanical properties of the cards and the minimal requirements of
the card slots and cartridges.
Section 12 defines the MultiMediaCard bus as a
universal communication interface and the electrical
parameters of the interface.
The standard compliance criteria for the cards and hosts are described in Section 13.
For achieving high data interchangeability, three basic file formats are defined in Section 14 as valid file
formats for the MultiMediaCard
Annex A contains additional information that is informative in nature and not considered a constituent part
of this specification. These Application Notes contain useful hints for the circuit and system designers,
helping simplify the design process.
Annex B lists the major changes between the previous and the current version of this specification.
As used in this document, “shall” or “will” denotes a mandatory provision of the standard. “Should”
denotes a provision that is recommended but not mandatory. “May” denotes a feature whose presence does not
preclude compliance, that may or may not be present at the option of the implementor.
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