POWER

Table of Contents

• Features Supported
• SysConfig Features
• Features NOT Supported
• Example Flow Diagram
• API
• Power Optimization Techniques Appnote

Power management offers significant extension of the time of batteries used to power an embedded application. The Power module is the Radar Power Management Framework which allows the device to optimize power consumption by reaching different low power modes as configured by the application.

Features Supported

• Entry to different low power states based on available idle time, thresholds and latencies for various low power states. In current version of SDK, following modes are supported :
  
  • Low Power Deep Sleep (LPDS) mode: This is the most power optimized state where most of the power domains are OFF. Check reference manual for more details.
    
  • Idle mode: Idle mode is a low power state where power consumption is reduced by disabling unused domains either by powering down the domain or clock gating etc. This mode
    is not as power efficient as LPDS but used when there is no enough time to get to LPDS or not efficient to get into LPDS. What all can be done in this mode
    is upto to the users based on their application and can be configured inside idle3 entry and exit hook functions.
    The power driver/example implements Idle3 state which is a TI defined idle state where all the peripherals are clock gated, FECSS and HWA are powered down (in hook functions)
    and APPSS core is put to deep sleep state(in power_idle3()). The core is waken-up using an RTI timer interrupt
    
• Programmable wakeup sources from LPDS
• Programmable hooks for LPDS entry and exit
• Programmable hooks for Idle3 entry and exit

SysConfig Features

Note

It is strongly recommend to use SysConfig where it is available instead of using direct SW API calls. This will help simplify the SW application and also catch common mistakes early in the development cycle.

• POWER instance name
• Enable / Disable option to use/not to use the framework
• Hook functions to add own sleep policy and init policy functions
• Configurablity for LPDS mode
  • Selection of wakeup sources from LPDS
  • Selection of wakeup pin if GPIO/SYNC_IO is configured as wakeup source
  • Selection of SRAM retention regions during LDPS
  • LPDS entry and exit hooks
  • Idle3 entry and exit hooks
  • State of debug module during LPDS
  • Option to park pins during LPDS (When a pin is parked, input and output are disabled)
• Threshold for different low power modes: Minimum time required to enter that particular low power mode
• Latency for different low power modes: Time required for entry and exit of that particular low power mode
  **Note: Threshold has to be always greater than latency.

Features NOT Supported

• Sleep mode is not supported

Example Flow Diagram

The driver init sequence is as below:

Driver Initialization

Driver execution flow is as below:

Driver Flow

API

APIs for POWER Module

Power Optimization Techniques Appnote

Application note on Power Optimization Techniques for xWRL6432 Low Power Radar can be found at https://www.ti.com/lit/an/swra754/swra754.pdf