SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
SmartReflex is a power-management technique used to control the operating voltage of a device to reduce its active power consumption.
With SmartReflex, the power supply voltage is adapted to the silicon performance in one way:
SmartReflex achieves optimal performance/power trade-off for all devices across the technology process spectrum.
The static correction of the device voltage level (see Figure 3-14) is based on the desired performance level and silicon performance characteristics of the device. As a result of process dispersion, each die has its specific silicon performance. The range of the process distribution defines the weak devices (low-performance silicon) and the strong devices (high-performance silicon).
A weak device is a device with the lowest performance tolerated for a process distribution; that is, at the typical voltage, the inherent maximum frequency is the lowest frequency of the chip distribution. Considered as the worst case, weak devices are used to constrain the target frequency of all the chips (OPP definition).
A strong device is a device with the highest performance tolerated for a process distribution. The inherent maximum frequency at the typical voltage is greater than the targeted frequency.
Figure 3-14 shows that with the SmartReflex voltage-control architecture, it is possible to compensate for the device silicon characteristics and obtain optimal performance characteristics. Based on the device characteristics, the device voltage level can be adjusted for specific performance level.
Figure 3-15 is a functional overview of the SmartReflex voltage-control architecture of the device connected to an external power IC.
SmartReflex voltage control consists of the following modules:
The SmartReflex module senses the frequency of internal ring oscillator and generates an error value that identifies the difference between the desired optimal voltage and the actual value and outputs this directly on dedicated hardware interface. This error value is set in an internal register (for software read, if necessary) and is also generated an interrupt to indicate error values outside acceptable limits.
The processor converts the error value to a command that defines the change in the output voltage required to bring it to the desired voltage level.
The device supports one operational mode for SmartReflex voltage control: