Best Canon PowerShot A640 SD Memory Card

Best PowerShot A640 SD Memory Card

The Canon A640 requires SD memory cards. 32GB is the largest capacity SD card that will work in the A640.

MultiMediaCards (MMC) can also be used in the camera. However, they are no longer made. If you have one, you can use it. If you do not have one, don’t buy one, they will cost more than an SD card.

SD memory cards described as SDXC or SDUC won’t function in the A640. These cards can be easily avoided as they have a storage capacity of 64GB or larger.

The SDHC format was announced in 2006. All 32GB cards that are currently being produced will have almost identical performance. You cannot go wrong buying the cheapest class 10 name brand card. At the time of writing this, the PNY Elite 32GB SD memory card has the best price.

Listed below are memory cards that can be used in the A640. With any of the cards listed below, you won’t have to worry about poor performance or SD memory card errors.

PNY Elite 32GB SD Card
Check price on Amazon
  • Sequential read speed of up to 100MB/s
  • Class 10, U1 rating delivers speed and performance for full HD photography and HD videography.
  • V10 video speed rating to capture uninterrupted HD video at 1920x1080 format
  • Compatible with point & shoot cameras, DSLR cameras, standard & advanced HD-enabled video cameras, and more
  • Reliable & Durable: Magnet Proof, Shock Proof, Temperature Proof, Waterproof
SanDisk Ultra 32GB SD Card
Check price on Amazon
  • Quick transfer read speeds up to 90MB/s.
  • Write speeds are not capable of recording 4k video.
  • Class 10 rating for Full HD video (1080p).
  • Waterproof, temperature proof, X-ray Proof, magnet-Proof, and shockproof.
Samsung EVO Plus 32GB SD Card
Check price on Amazon
  • UHS Speed Class 1 (U1) supports Full HD video and burst shots. 130MB/s transfer speeds1 let you upload footage to your PC in an instant.
  • Built to survive tough conditions and heavy usage, whether you’re at home, outside, or on the go. Backed by 10-year limited warranty.
  • Highly durable with comprehensive 7-proof protection.
  • Backed by a 10 year warranty.

Best SD Cards

Lexar, PNY, Samsung, and SanDisk both make excellent memory cards. Avoid ordering cards from cut-rate third party brands.

Low-cost cards are more probable to experience file corruption, meaning you will lose all of your shots contained on the card. A minimal difference in price is not worth the reduction in construction quality.

Buy a smaller capacity card in case you want to save some money. They should be a little bit lower in price and you won’t have to stress out about the SD card having data failure.

Be aware that, SD card issues are very rare. Only a couple cards have failed out of the loads I have acquired over time. Both memory cards were previously owned house cards that were bundled with the purchase of pre-owned cameras.

Canon A640 SD Card Compatibility

4 different technical specs of Secure Digital (SD) cards are currently being manufactured. The Canon A640 is limited to using SD memory cards. Each updated memory card spec boosts the read/write speeds and max capacity when compared with the former standard.

Secure Digital memory card readers are backward compatible. A card reader built into a digital camera that can use SDXC cards will also be able to use SDHC and SD memory cards.

The Canon A640’s card reader is only compatible with the original two SD card technical specs. SDXC or SDUC SD cards are not going to be compatible.

  • Secure Digital (SD) - These memory cards have a maximum capacity of 2GB and are compatible with the A640.
  • Secure Digital High Capacity (SDHC) - The capacity of these memory cards range from 4GB to 32GB and are also compatible with the A640.
  • Secure Digital eXtended Capacity (SDXC) - The capacity of these memory cards range from 64GB to 2TiB.
  • Secure Digital Ultra Capacity (SDUC) - The capacity of these memory cards range from 4TiB to 128TiB.

Canon A640 Memory Card Full Error

SD Card Contacts

Trying to use an SD memory card that has a storage capacity of 64GB or larger in the A640 results in the digital camera to show an error message.

Use an SD card that has a capacity of 32GB or less to fix the error.

If you are using an SD memory card that is 32GB or a smaller capacity, and the card is not working, format the memory card in the camera.

Speed, Class, & Capacity

SD Card Image Capacity

Here is an estimation of the total number of large JPEGs you could expect to save on an SD memory card.

  • 4GB - 1920 images
  • 8GB - 3840 images
  • 16GB - 7680 images
  • 32GB - 15360 images

Memory Card Speed

Speed ratings for SD cards are established by the sequential read and write speeds. The speed of the SD memory card is important in the event that many pictures need to be written to the SD memory card.

SD Card Speed Class Rating

SD Card Speed Class

The Class speed rating of an SD card is related to the sustained write speed of the memory card. A Class speed rating of 2 means that the memory card can sustain a write speed of a minimum of 2MB per second.

  • Class 2 - 2MB/s
  • Class 4 - 4MB/s
  • Class 6 - 6MB/s
  • Class 8 - 8MB/s
  • Class 10 - 10MB/s

The best rating an SD memory card can obtain is Class 10. There are cards that are a lot faster than 10MB/s. Those memory cards use other solutions, such as UHS (Ultra Highspeed Bus), which use a separate rating criteria.

Sustained write speeds of 2MB, 4MB, 6MB, or 8MB per second means the card has a speed class of 2, 4, 6, or 8. Cards that have write speeds of 10MB/s or faster are rated as Class 10.

MultiMediaCard Compatibility

The MultiMediaCard standard was unveiled in 1997 by SanDisk and Siemens AG. MMC cards are close in size to an SD memory card, but they are a little slimmer.

MMC cards that are going to function in the Canon A640 consist of the original two versions. Compatible cards will be labeled as MMCplus or MMC. Later generations won’t function correctly with the Canon A640

Avoid buying an MMC memory card. Suitable MMC cards for the A640 are not at present being built. Because of this, they are extremely hard to get used and overpriced.


Buy an SD memory card for the Canon A640 based on price. An expensive card isn’t going to improve performance. As long as it is a speed class 10 card, you will be fine. My recommendation is the PNY Elite 32GB SD memory card.