Bluetooth Smart ICs reduce current demands

July 15, 2016 // By Graham Prophet
Toshiba’s latest integrated Bluetooth LE (low energy) ICs claim a 46% current reduction over prior products, extending operating life on power sources such as coin-battery powered devices.

For Bluetooth Low Energy (BLE) version 4.1, the TC35678FSG, TC35678FXG and TC35679FSG incorporate a high-efficiency DC-DC converter and a low-power circuit design for current reduction of nearly 46% when compared to prior products, such as the TC35667FTG. At a 3V voltage supply, the ICs achieve peak current consumption of 3.6 mA, in transmitting mode and 3.3 mA in receiver mode. In deep sleep mode, this is reduced to 100nA.


Both the TC35678FXG and TC35678FSG incorporate 256 kB of built-in flash ROM to store user programs and data in stand-alone operations without a need for an external host MCU. Dedicated memory capacity for user programs is now extended from 64 kB in previous products to 100 kB in both ICs, contributing to greater expansion options for application programs. This built-in flash ROM eliminates any need for external EEPROM.


The TC35678FXG is a repackaged version of the TC35678FSG, in a QFN60 package that extends the number of general purpose IOs from 16 to 32. It is suitable for use in equipment such as keyboards and remote controls that require a large number of control pins. In comparison, the TC35679FSG has no built-in flash ROM and can consequently achieve even lower current operation. It achieves long operating times for applications powered by small coin batteries. For example, using a CR2032 type coin battery, the new IC can carry out beacon operation for over a year [assumption; 220 mAh battery and 2-second beacon interval time].