SDMJ-32 SanDisk, SDMJ-32 Datasheet - Page 20

• Manufacturer Part Number: SDMJ-32
• Manufacturer: SanDisk
• Type: MultiMedia Cardr

Specifications of SDMJ-32

• Density: 32MByte
• Operating Supply Voltage (typ): 3.3V
• Operating Temperature (min): -25C
• Operating Temperature (max): 85C
• Package Type: MMC
• Mounting: Socket
• Pin Count: 7
• Operating Temperature Classification: Commercial
• Operating Supply Voltage (min): 2.7V
• Operating Supply Voltage (max): 3.6V
• Programmable: Yes
• Lead Free Status / RoHS Status: Compliant

Revision 1.3
© 2005 SanDisk Corporation
Figure 3-3
After power up, including hot insertion
transactions until CMD1 is received.
CMD1 is a special synchronization command used to negotiate the operation voltage range
and to poll the cards until they are out of their power-up sequence. Besides the operation
voltage profile of the cards, the response to CMD1 contains a busy flag, indicating that the
card is still working on its power-up procedure and not ready for identification. This bit
informs the host that the card is not ready. The host must wait, while continuing to poll the
cards, until this bit is cleared. The MultiMediaCard/RS-MultiMediaCard initialization
sequence will be completed within 500 ms.
The bus master has the task of getting the individual cards and the entire card system out of
idle state. Because the power-up and the supply ramp-up time depend on application
parameters such as the maximum number of cards, the bus length and power supply unit,
the host must ensure that the power is built up to the operating level (the same level which
will be specified in CMD1) before CMD1 is transmitted.
After power-up, the host starts the clock and sends the initializing sequence on the CMD
line. This sequence is a contiguous stream of logical “1”s. The sequence length is the
maximum of 1 ms, 74 clocks or the supply ramp-up time; the additional 10 clocks (over the
64 clocks after what the card should be ready for communication) are provided to eliminate
power-up synchronization problems.
2
Inserting a card when the bus is operating
Power-up Diagram
3-5
2
MultiMediaCard and RS-MultiMediaCard Product Manual
the card enters an idle state and ignores all bus
Chapter 3 –Interface Description
07/15/05