Thursday, 10 March 2011

Portable memory range is gamma safe for medical OEMs

Nexus GB has launched Datakey Electronics’ new GammaSafe memory token for the UK medical device manufacturing sector. The token is a non-volatile, reprogrammable, portable memory device that survives gamma sterilization with no loss of data. The GammaSafe system also allows medical device manufacturers to easily add anti-counterfeit and limit-use capabilities to disposable attachments that are sterilized using gamma radiation.

The GammaSafe memory token contains four kilobits of non-volatile, re-writable memory. This is accessed using an SPI bus and is functionally similar to an SPI EEPROM. But unlike actual EEPROM devices, which experience data loss and even device failure when exposed to significant doses of gamma radiation, GammaSafe memory tokens have been proven to withstand up to 45kGy (4.5Mrad) of gamma radiation with no data loss.
Medical device manufacturers who produce single-use or limited-use disposable attachments, such as catheters, filters, tubing and medical lasers that plug in to a base controller, can now add a non-volatile memory device to the attachment, even if their attachments contain no active electronics.

The GammaSafe memory token can store an encrypted product authentication code to protect against counterfeit disposables. The disposable's model number and associated parameters, along with calibration information can be written to the GammaSafe token during production; then, in the field, this data can be automatically transferred to the base controller unit, eliminating the chance for human error from incorrect data entry.

"Our rugged SlimLine memory tokens have been used with disposable medical devices for more than fifteen years," explained Victoria Barrett, PR and marketing director for Nexus GB. "Our traditional SlimLine tokens survive both EtO and autoclave sterilization methods. With the addition of the GammaSafe line, we have a portable memory solution for OEMs of medical disposables no matter which sterilization method they use; EtO, autoclave or gamma."

In addition to the memory token, the GammaSafe product line includes a line of mating receptacles. The GammaSafe receptacles are based on Datakey Electronics' proven SlimLine receptacle design and are available in through-hole (GR4220PCB), surface-mount (GR4220SMT), and panel mount (GR4310 and GR4410) models. The panel-mount receptacles are available in splash-proof (IP65-rated), immersion (IP67-rated), and EMI-reduction versions, supporting a variety of medical device applications, especially those with wash-down requirements. GammaSafe receptacles accept both GammaSafe and SlimLine memory tokens.

Unlike RFID solutions that require OEMs to integrate complicated RF transceiver circuitry and an antenna into their embedded designs, integrating the GammaSafe memory system requires only the addition of a simple receptacle. No complex circuitry is needed; he contacts of the GammaSafe receptacle simply connect directly to the microcontroller's SPI port. When the GammaSafe memory token is inserted into the receptacle, the microcontroller can read and write to it just as if it was an SPI EEPROM IC soldered to the board. Furthermore, because the GammaSafe system is contact-based, as opposed to wireless, there is no ambiguity as to which memory device is being read, a frequent concern with RFID and other wireless systems.

The GammaSafe memory token is offered with an optional integrated tether. The optional tether consists of a 5-inch (12.7 cm) cable-tie that has been pre-looped and integrated into the head of the memory token. This allows OEMs an easy way to attach the GammaSafe token to their disposable devices.

The GammaSafe memory token also features an optional sterilization indicator, which is housed within a recessed window on the front side of the token. Before sterilization, the indicator is orange in colour. After gamma sterilization (10kGy dosage or more) the indicator changes to a vivid red colour. This optional feature enables medical personnel to confirm at a glance that the sealed medical device they are about to open has undergone gamma sterilization.

Nexus GB