FEATURE MEDICAL ELECTRONICS WHEN CHIPS ARE GOOD FOR YOUR HEALTH
Heiner Tendyck, system LSI marketing department at Toshiba Electronics Europe discusses how the latest Bluetooth LE chips are providing a fully integrated low power solution for modern medical devices The TC35678 incorporates 256KB of
B
luetooth is clearly a leading connectivity technology for modern
medical devices as it requires incredibly little energy to operate. Bluetooth low energy (Bluetooth LE) having evolved out of the mobile phone sector now includes various highly secure encryption techniques, which secure sensitive personal data during transmission so again well suited to the medical market. The new Bluetooth standard (BT4.2) adds a lot of security features. Inbuilt privacy features mean that Bluetooth devices are difficult to track, and new elliptic curve algorithm combined with intelligent key management form a significant barrier to eavesdropping and data manipulation. The Bluetooth frequency-hopping radio virtually eliminates network interference and provides high levels of RF noise immunity, thereby ensuring a strong and reliable connection at all times. By combining Near-Field
Communication (NFC) technology with Bluetooth it is now possible to realise a secure pairing and a secure data connection. Although, at first, this may seem to be complex, in practice it is quite simple and intuitive. Firstly, the healthcare device is placed close to the NFC-enabled smartphone or tablet. Energy coming from the mobile device will “wake” the Bluetooth device up, which transmits its credentials securely via NFC.
As the healthcare device detects that the smartphone is present, it accepts a pairing request and exchanges a passkey securely via NFC. This secure transfer via NFC prevents the passkey being intercepted. The pairing is immediately complete and the devices’ are able to open a secure Bluetooth data communication that starts via the Bluetooth antenna. Apart from the obvious security, this approach also saves power. NFC power consumption is negligible and Bluetooth is only turned on once the NFC connection is detected.
BLUETOOTH SEMICONDUCTORS Two new ICs that support Bluetooth low energy version 4.2 communications have been developed by Toshiba. The
14 SEPTEMBER 2017 | ELECTRONICS
built-in Flash ROM to store user programs and data without a need for an external host MCU. Dedicated memory capacity for user programs is now extended to 83KB, giving greater expansion options for application programs. This built-in Flash ROM eliminates any need for external EEPROM and contributes to reductions in both cost and mounting-area, by reducing the number of external parts. In comparison, the TC35679 has no
built-in Flash ROM and can consequently achieve even lower current operation. This device can also be combined with almost any external host MCU, so you can choose and scale the MCU to the required calculation performance. One of the most useful features of these devices is the on-chip RF matching network. By removing the need for a matching circuit a total of six LC elements are removed from the external PCB. This reduces the PCB area required by around 20% as well as reducing the BOM cost. The company offers a complete hardware and software development ecosystem. From a hardware perspective, host-mode starter kits are available as well as a standalone development kit that includes USB and SWD interfaces.
TC35678 and TC35679 achieve low current consumption and are ideal for use in healthcare devices. A highly efficient DC-DC converter and
low-power circuit reduce current by nearly 46% when compared to previous products. With a 3V supply, the ICs achieve peak current consumption of 3.3mA, in both the transmitting and receiver mode. In deep sleep mode, this is reduced to 50nA. This is (at the moment) the lowest peak current in the market, allowing devices to run up to four years+ on a single CR2032 coin cell battery.
Figure 1: Block diagram of the TC35678 and TC35679 ultra low power Bluetooth Low Energy chips
Figure 2: On-chip RF matching saves PCB area and reduces BOM cost
Figure 3: The comprehensive SDK supports Bluetooth Low Energy and NFC
A CONNECTED HEALTHCARE NETWORK Healthcare is a rapidly growing market with new devices and new functionality constantly being developed. Bluetooth, especially Bluetooth Low Energy, plays a pivotal role in connecting these healthcare devices to the Internet via smartphones and tablets bringing unprecedented levels of convenience for users and healthcare professionals. There are however significant
challenges relating to power consumption, secure pairing, reduced size and reduced cost. A new generation of BLE devices is helping to meet those challenges.
Toshiba Electronics Europe
www.toshiba.semicon-storage.com T: +49 (0) 211 52960
/ ELECTRONICS
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64
