MMC 4.2 SOLUTIONS
| PRODUCT OVERVIEWS (pdf) |
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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 players, pagers, electronic toys, etc. Targeted features are high mobility and high performance at a low cost price. It might also be expressed in terms of low power consumption and high data throughput at the memory card interface.
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 MultiMediaCard mode. For compatibility to existing controllers the cards may offer, in addition to the MultiMediaCard mode, an alternate communication protocol which is based on the SPI standard.
To provide for the forecasted migration of CMOS power (VDD) requirements and for compatibility and integrity of MultiMediaCard systems, two types of MultiMediaCards are defined in this standard specification, which differ only in the valid range of system VDD. These two card types are referred to as High Voltage MultiMediaCard and Dual Voltage MultiMediaCard.
The purpose of the system specification is the definition of the MultiMediaCard, its environment and handling. It gives guidelines for a system designer. The system specification also defines a tool box (a set of macro functions and algorithms) which helps reducing the design-in costs.
System Features
- Targeted for portable and stationary applications
- System Voltage (VDD) Range:
- Designed for read-only, read/write and I/O cards
- Card supported clock frequencies 0-20MHz, 0-26MHz or 0-52MHz
- Maximum data rate up to 416Mbits/sec.
- Card support for three different data bus width modes: 1bit (default), 4bit and 8bit
- Password protection of data
- Basic file formats for high data interchangeability
- Application specific commands
- Correction of memory field errors
- Built-in write protection features (permanent and temporary)
- Simple erase mechanism
- Full backward compatibility with previous MultiMediaCard systems (1 bit data bus, multi-card systems)
- New hosts retain full compatibility with previous versions of MultiMediaCards (forward compatibility).
- Two form factors: Normal size(24mm x 32mm x 1.4mm) and Reduced size (24mm x 18mm x 1.4mm)
- Multiple command sets supported
| High Voltage MultiMediaCard | Dual Voltage MultiMediaCard | |
| Communication | 2.7 - 3.6 | 1.65 - 1.95, 2.7 - 3.6 |
| Memory Access | 2.7 - 3.6 | 1.65 - 1.95, 2.7 - 3.6 |
| VDD range: 1.95V - 2.7V is not supported. | ||