technology insights and blood pressure monitors
Technology insights are not just there for the taking. If they were easy the area would not be filled with gee-whiz and i-candy. They require background, context and “looking around”. The latter includes consuming multiple sources or types of information. The whole picture is rarely in one location.
back to Omron
An article from last fall discussed the role of semiconductors in medical devices in general and the Omron HEM-790ITCAN in particular. It could have accomplished so much more. Instead of looking around it focused on one source and got lost in terminology. Where does the Omron HEM-790ITCAN fit? Does the meaning of sphygmomanometer matter?
looking around and asking questions
Q: What does Omron say about the HEM-790ITCAN and how is it being marketed?
A: The device’s page on the Omron website discusses the detection of hypertension and an irregular heartbeat. A glance at figures in the manual suggests these functionalities are available on the device itself, so there is logic and software operating on it. It is also indicated that up to 200 readings, in total, can be stored between two patients, so there has to be memory. This memory would have to be non-volatile to maintain this data when the device is turned off. This might take the form of a battery backed SRAM or maybe EEPROM. The device page also highlights two trademarked terms “Intellisense” and “Comfit”, with the former being combined with the terms accurate and comfortable, while the latter is used to describe a cuff. Both phrases suggest there must be advances in the cuff. We are starting to see what technology Omron considers important.
Q: Are there any patents around technology that might be in this device?
A: Yes. A very basic search of issued patents in the USPTO found 16 patents assigned to Omron containing “blood pressure” in the title. Within these are US 7,018,335 and 7,775,984 entitled “Blood Pressure and Cardiovascular Disease Risk Analyzing Program” and “Electronic Blood Pressure Monitor and Data Processing Apparatus”, respectively. There are also numerous patents related to a cuff. The presence of issued US patents associated with both the cuff and the monitor support the above marketing message. Again, we are given glimpses of what Omron considers important.
Q: What does the reverse engineering tell us in terms of the use of the implemented integrated circuits?
A: The Cypress and Toshiba ICs are shown in the board level photographs on page 55 of the article. Otherwise the pressure sensor, USB port, two TSOPs, what appear to be some high voltage parts and discretes are visible. At this level the various die markings are unclear but at least one of the 8-pin TSOPs might be non-volatile memory. There will also some software for running the various data processing algorithms stored somewhere. Whether it is in the second TSOP or onboard one or both of the micro-controllers is unclear. What is clear is that a system to collect, manipulate and store data is provided by the device. Finally, it is somewhat interesting that the two die markings have a 1999 copyright, indicating they are older designs. In the end that is fine as not much computing power is needed for this application.
While only the surface has been scratched here there is a much more interesting story to be told when you look around, explore available information and pull it together.