I'm designing a product which requires total consumption as low as possible. I came across adxl362 with ultra-low power consumption. However, I didn't figure out how to power it efficiently.
There product will have a LiPo rechargeable battery as a system power. Its voltage will be between 2.7v ~ 4.7v . A main MCU with internal LDO and DCDC, which could work between 1.8v ~ 3.6v, but with recommended to work above 3.0v due to current leakage in lower power supply , an ADXL362 could act as a motion switch .
I intent to use a buck-boost regulator to power the main system under 3.0v, i.e. main MCU. But how to drive adxl362 efficiently ? adxl362 need to work when main MCU works or not. The buck-boost regulator's quiescent current is even higher than adxl362.
How about I use a voltage references as a power source ?
The power supply for the ADXL362 must be between 1.6 and 3.5V. Is it possible to use an ultra low power voltage reference such as ADP165 in your application? A quick glance at the spec table for this regulator seems to indicate that it should be a good alternative to power on the ADXL362 while the MCU is not on.