Wearable devices, such as smart watches, are getting smarter and more power hungry. This is because more CPU processing is required for digital signal processing, such as for voice recognition. It causes an increase in the current consumed by even our ultra-low power RE01 CPU, affecting the battery life. Since the battery size of wearable devices is generally quite small (i.e., 120mAh), this winning combo reference design replaces the RE01 MCU’s internal LDOs with external ISL9123 buck regulators. With this reference design, the RE01 CPU processing current can be reduced by half, directly contributing to an extended battery life.​

System Benefits​

  • The ultra-low ISL9123 buck regulator enables extended battery life in wearable devices, which require very loaded CPU processing for features such as voice recognition​
  • ISL29125 light sensor controls the brightness of the backlight​
  • The READ2302 op amp amplitudes the output of the MEMS microphone to detect the voice from the RE01 14-bit ADC​
  • The ISL9205 battery charger charges the Li-ion battery


 

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