The figure below provides conceptual illustrations of the development processes for a digital power supply and for a conventional analog power supply.
It is possible to modify the operation of a digital power supply simply by making changes to the software (parameters). Reusability of existing resources is high, and it is easy to derive new products from existing ones. In addition, there is a high affinity with communication functions, making it possible to develop products that match market needs in a short period of time.
Differences Between Digital Power Supply and Conventional Analog Power Supply
A digital power supply can also reduce costs. The shorter development time lowers the cost of development, and since the specifications can be modified in software, multiple related products can be developed based on the same board platform. In addition, the Renesas RL78/I1A microcontroller for digital power supplies integrates essential peripheral functions on-chip, so the cost of external IC devices is greatly reduced.
Example of Cost Reduction by Using Digital Power Supply
Digitizing the power supply makes it possible to boost power supply performance. The figure below shows contrasting examples of feedback control using analog and digital means. When a sudden change in load occurs, the output variation is smaller with a digital configuration than with an analog one. This means that there is no longer any need for capacitors to suppress LED flicker when dimming the brightness or as a countermeasure for ripple currents. Finally, digital power supply technologies such as variable gain and auto-tuning can be used to increase responsiveness, maintain stability, and suppress variability in ways that are not possible using analog devices.
Digitizing the Power Supply for Improved Performance