CARDSPEED - Card Readers and Memory Cards

Memory Cards Information

Card Types Overview

Leaving out the huge PCMCIA cards, we get interesting results:
Area (rectangular):   SmartMedia   -   CF-I / CF-II   -   MS / MS Pro   -   SD / MMC / µcard
Volume (cubic):   CF-II   -   CF-I   -   MS / MS Pro   -   SD   -   Smart Media

Card Speed Overview

This is the detailed view on the lower end of the full scale:

In the range up to 25MB/s, CF, SD, MMC and MS are equally good represented. The theoretical limits in this range are 19.07MB/s for the MS PRO mode (4bit 40MHz), 23.84MB/s for the fastest SD 1.1 mode (4bit 50MHz), the same for the fastest CF PIO mode (PIO-6), and 24.80MB/s for the half-speed modes of MMC 4 (4bit 52MHz or 8bit 26MHz). Only MMC 4, MS PRO-HG and the CF UDMA modes offer faster speed.

Below is the full range of current memory card interface standards. The top row shows the memory card speed ratings on the left side and the theoretical and real-world data rates of popular host interfaces on the right side.

The bottom row shows the memory card interface standards. Only the 8bit 52MHz mode of MMC 4, the 8bit 60MHz MS PRO-HG and the CF-ATA modes from UDMA-2 to UDMA-6 offer higher speeds than 25MB/s.

USB 2.0 Card Readers should be fine for up to 30MB/s (200x). The fastest FireWire 400 (1394a) CF readers should just be able to keep up with the claimed 40MB/s (266x) speed of the SanDisk Extreme IV CF, while their FireWire 800 (1394b) Extreme CF reader should be able to show significant improvement with the next generation of Extreme CF cards. CardBus adapters should have even more potential than that, but the controller chips used often limit the data rates well below the performance of current USB 2.0 readers - especially for media other than CF.

Card Adapters Overview

Card Sized Adapters

This is a list of memory card adapters that have exactly the size of another card type.

PCMCIA / PC-Card Adapter

CF-I to PCMCIA-II

This is the most commonly available adapter type for PCMCIA. The CF-I card with a thickness of 3.3mm is inserted into the PCMCIA-II card with a thickness of 5mm. The adapter just contains wiring from the 50-pin CF slot to the 68-pin PCMCIA connector.

CF-II to PCMCIA-II

This solution is a little more tricky, because CF-II and PCMCIA-II have exactly the same thickness. The PCMCIA-II adapter has a big notch, and both, CF-I and CF-II cards, are only guided by two rails. In most cases, the pins of the CF slot are protected by a spring-loaded protective shield with matching holes for the pins of the CF slot. As stated before, the adapter just contains wiring from the 50-pin CF socket to the 68-pin PCMCIA connector.

Other cards to PCMCIA-II

The PCMCIA-II format is large enough to fit any of the other card types. There is just more or less electronics necessary to translate between the different interfaces.
There are multi-card adapters available where you can insert one of multiple card types at a time, usually SD, MMC, MS, MS Pro and SmartMedia.
The latest models also support xD-Picture Cards, but the big challenge is the limited slot area and the different locations of the contacts. Some of the adapters supporting xD-Picture cards won't accept SmartMedia.
In general, the cards are inserted completely into the PCMCIA Adapter from the front edge so that the cards sit flush with the edge. This means that the smaller card types can only be used with the respective adapters. There are special adapters that don't accept SmartMedia and have two slots next to each other: One slot for the regular types and a second slot for MS Duo and miniSD.

CardBus Adapter

CardBus adapters (PCMCIA Type II size)

There are CardBus adapters available which are a quite expensive way of dealing with the bad performance of the old PCMCIA-ATA interface. The following adapters are available:

• CardBus CF-I/II adapter
• CardBus SD/MMC adapter
• CardBus Memory Stick adapter
• CardBus Multi Adapter (SD/MMC/MS/xD)

CF Adapter

SD/MMC to CF-I card

This is a special adapter solution which was first distributed by Minolta and Panasonic. In the meantime, these adapters are also available from cheaper sources.
The SD or MMC cards can be inserted fully into the CF-I adapter, so that it can be used in a regular closed CF type I slot. The adapter card contains the necessary electronics to translate between the two interfaces.
There are also CF-II adapters and longer CF-I adapters available. It should be obvious that they are only of limited use.

xD-Picture Card to CF-I card

This is another special adapter solution distributed by FujiFilm and Olympus.
The xD-Picture Card can be inserted fully into the CF-I adapter, so that it can be used in a regular closed CF type I slot. The adapter card contains the necessary electronics to translate between the two interfaces.

MS Duo to CF-I card

This is a special adapter solution distributed by SONY.
The Memory Stick Duo can be inserted fully into the CF-I adapter, so that it can be used in a regular closed CF type I slot. The adapter card contains the necessary electronics to translate between the two interfaces.
This kind of adapter solution is not possible for the regular sized Memory Sticks, since their length (50mm) exceeds the width of a CF card (42.8mm).

Memory Stick Adapter

MS Duo to MS / MS Pro Duo to MS Pro

It was a design criteria of the Memory Stick Duo that it can be inserted into a passive Memory Stick adapter card that just connects the respective pins.
The Memory Stick Duo even has the same connector layout as a regular sized Memory Stick. There are Memory Stick slots that have special guides so that both, regular sized Memory Sticks and Memory Stick Duo can be inserted. Inserting a Memory Stick Duo in a regular Memory Stick slot can result in bent or damaged connectors inside the slot.

Memory Stick Micro (M2) to Memory Stick PRO

It was a design criteria of the Memory Stick Micro (M2) that at can be inserted into a passive Memory Stick PRO adapter.

Memory Stick Micro (M2) to Memory Stick PRO Duo

Unlike microSD or MMCmicro, the Memory Stick Micro have special guides that allow the use of adapters without top cover. This makes it easier to build Adapters from Memory Stick Micro to Memory Stick PRO Duo. But these adapters are still hard to find.

microSD to Memory Stick PRO Duo

This was the first solution that allowed a "foreign" memory card type to be used in Memory Stick slots.

MBridge to Memory Stick PRO Duo

The MBridge is a hybrid SD/MS flash module that comes with different adapter shells. One of the adapter allows the use of the MBridge as Memory Stick Duo. An adapter to full-size Memory Stick is not included, but of course regular MS Duo to MS adapters can be used.

SD Adapter

miniSD to SD card

It was a design criteria of the miniSD format that miniSD cards can be inserted into a passive SD card adapter that just connects the respective pins. The miniSD cards use the same interface, but a different connector layout.

microSD/TransFlash to SD card

It was a design criteria of the microSD or TransFlash cards that they can be inserted into a passive SD card adapter that just connects the respective pins. The additional ninth pin of the SD cards is just a redundant ground connector.

microSD to miniSD

Although the difference in thickness is only 0.4mm, it is possible to build adapters, but they are hard to find.

MMCmicro to SD slot

It was a design criteria of the MMCmicro that they can be used with a passive adapter that just connects the respective contacts. However, the regular adapters supplied with most MMCmicro have SD form factor, so that they only fit SD/MMC combo slots. Besides the form factor of these adapters, there is no disadvantage, because MMCmicro only use 4 bit of the MMCplus interface and the lower 4 bit can be transfered using the 9 pins of the SD interface.

miCARD to SD slot

It was a design criteria of the miCARD that it can be used with a passive adapter that just connects the respective contacts. Due to the thickness of 1.95mm, the miCARD can only be used in CD/MMC combo slots. The passive adapter connects the miCARD to the respecitve pads. Currently it is unknown whether the miCARD will support only 4-bit or the full 8-bit MMCplus interface, and whether the adapter connects all eight data lines.

MBridge to miniSD and SD

The MBridge is a hybrid SD/MS flash module that comes with different adapter shells. The MBridge module has exactly the same pad layout as miniSD, the adapter shell just adjusts the width and thickness to fit a miniSD slot. An adapter from miniSD to SD is also included.

MMC Adapter

RS-MMC to MMC

The RS-MMC ist just a short version of the MMC with exactly the same connector layout. For MMC slots where the card has to be inserted deeper than the length of a RS-MMC there are snap-on adapters available. These adapters simply extend the RS-MMC physically, so that it can be handled in the same way as a regular sized MMC.

MMCmicro to MMC

Although there is only a difference of 0.3mm between MMCmicro and MMC, there seem to be MMCmicro to MMC adapters available. The main problem ist that the contacts have to go underneath the MMCmicro, on top there can be a very thin layer as cover.

Cards with USB Connector

SD with USB Plug

There are SD cards with built-in USB plug available. Some of the cards have a detachable part, others have a flip-over part that reveals the USB plug. The cards introduce more or less mechanical problems with snap-in/snap-out SD slots, so they should always be inserted and removed with special care.

microSD to SD with USB plug

This is the most complicated type of adapter: The microSD is inserted at one side of the SD/USB card. This does not leave much room for the contacts and the USB controller.

miCARD to USB

It was a design criteria of the miCARD that it can be directly plugged into a regular USB host connector. This is the reason for the width of 12mm and the thickness of 1.95mm. Only the length of the miCARD could be chosen by the designers.

Other Adapters

PCMCIA slot to ATA

The PCMCIA interface can be hardwired to the ATA interface. Pleaso note that only PCMCIA-ATA cards will work this way.

CF slot to ATA

Because CF can be hardwired to PCMCIA, it should be obvious that a CF slot can be hardwired to the ATA interface. There are adapters available with 40-pin ATA or 44-pin ATA connector. The power connector is either a large harddisk type or a small floppy disk type power connector. Only CF cards and microdrives that are compatible with the CF-ATA protocol will work. CF cards and Microdrives should accept both, 5V and 3.3V operating voltage. With these adapters, the CF slot is usually powered directly from the 5V line of the power connector.

PCMCIA slot to CF card

The two hardwired solutions from CF to PCMCIA also work the other way round. PCMCIA memory cards should work without any problems. PCMCIA harddisks might exceed the power limit of the CF slot, especially for CF slots of host powered card readers.
Even some PCMCIA I/O cards will work if you can install the drivers on the host device. In general, this only applies to PDAs and Pocket PCs.

xD-Picture Card to SmartMedia

It was a design criteria of the xD-Picture Card to be electrically compatible to the SmartMedia interface. The 18 pins of the xD-Picture Card can be hardwired to the 22 connectors of a SmartMedia Card. If you look closer at a SmartMedia card, you will notice that some of the 22 contacts are connected to each other.
Please note that SmartMedia are limited to 128MB by design. This means that xD-Picture Cards of more than 128MB will most likely not work when used in a SmartMedia slot together with such an adapter.
If you still think that you need such an adapter, check the prices first. I have seen adapters advertised in the range from 4.50 to 20 Euro.