High flexibility and high performance give rise to a new generation of digital power controllers

In the field of power supply controllers, digital power supplies face two major challenges. The first is flexibility, which is actually what engineers expect from digital power supplies. They always hope to obtain the greatest flexibility through digital power supply controllers, and use software to enable digital controllers to achieve various power supply requirements required in the design. Secondly, today's switching power supplies, especially isolated switching power supplies, are full of very fast changes inside, so the power supply controller must be able to quickly process these high-speed signals, and the programmability of software and the detection and processing of high-speed signals are often a contradiction. Texas Instruments (TI) has a complete series of analog and digital power management and MCU optimization solutions that can fully meet the needs of all digital power supply designs and solve this contradiction well.

In the field of digital power supply, TI has a very wide range of product categories. As shown in Figure 1, from left to right, TI's products cover the entire product series from analog to semi-analog to full digital control. On the left is the analog solution that plays an important role in isolated and non-isolated power supplies. In the middle is a hybrid solution, whose core is the analog circuit, but the digital interface has been integrated with the internal analog core. On the right is a pure digital power supply solution, including TI's latest product, the isolated digital power supply UCD3000 series. In this product series, UCD3138 is mainly launched to meet the needs of Chinese server and communication manufacturers.

Figure 1 TI's overall digital power product line

UCD3138 is a highly integrated and configurable digital power management controller that can improve power density and reliability for various power topologies in servers, telecom rectifiers, and high-power DC/DC modules. In the UCD3138 digital power architecture shown in Figure 2, the upper part is fully programmable hardware. Its foundation is hardware, which is optimized for power application architecture. This hardware is a pair of state machines, which can achieve high flexibility when combined with the ARM7 located below. Since the foundation of the state machine is hardware processing, the upper and lower parts are combined together, and engineers can flexibly set its functions through programming.

In isolated power supplies, whether for servers or communications applications, the requirements for power supplies are getting higher and higher, with higher efficiency, integration and overall performance. The digital control function of UCD3138 can help designers further leverage the power system, including reusing hardware designs on multiple platforms, adjusting performance and controlling parameters for each application to achieve multi-functions, thereby accelerating the product's time to market. In particular, UCD3138 integrates a powerful 32-bit microprocessor, high-speed and high-precision data converters, multiple programmable hardware control loops, and different communication engines in a small 6 mm x 6 mm package, fully meeting all the requirements of the isolated power supply mentioned above.

Simple and easy-to-use graphical user interfaces (GUIs) and development tools are the key to the rapid promotion of digital power supplies. After all, most engineers today are accustomed to the design of analog power supplies. Digital power supply development tools, including feature-rich full-voltage evaluation boards, development kits, reference designs, application firmware source code, programmers' manuals, and Code Composer Studio software development environments, allow designers to easily transition to the new usage habits.

Figure 2 UCD3138 optimized power architecture