Zotac Z68-ITX WiFi Motherboard

Voltage Regulator

The CPU voltage regulator circuit of the Zotac Z68-ITX WiFi has six phases for the CPU main voltage (Vcc a.k.a. Vcore), two for the CPU VTT voltage (integrated memory controller and L3 memory cache), and one for the CPU VAXG voltage (integrated video controller). Therefore, it uses a “6+2+1” configuration.

Figure 9: Voltage regulator circuit

Figure 10: Voltage regulator circuit

Each phase is controlled by a Renesas R2J20651NP integrated circuit, which combines the three required transistors (“high side,” “low side,” and “driver”) in a single chip. It also allows the switching clock to be at 1 MHz, which allows efficiency to be over 90%. (Usually, voltage regulator circuits switch at 250 kHz.) Integrated circuits with those characteristics are known as “DrMOS.”

This motherboard uses high-end solid ferrite-core coils, which present less energy loss than iron-core coils (i.e., they improve efficiency) and SMD (surface mount device) capacitors, also known as highly-conductive polymerized or simply Hi-c.

If you want to learn more about the voltage regulator circuit, please read our tutorial on the subject.