RC5035

· Dual 3.3V/2.8V power supply for Intel Pentium P55C and Cyrix^® processors requiring separate voltage planes
· Programmable dual power supply for high current loads

The RC5035 combines a switch-mode DC-DC converter with a low-dropout linear regulator. In addition, it integrates the circuitry required to switch the DC-DC converter output between 3.5V and a user-selectable voltage from 1.5V to 3.6V as well as an enable function to allow the linear regulator to be turned off when not required. Using minimal external components, the RC5035 can be conÞgured to directly implement the two supply situations required in a P54/P55 ßexible motherboard application. In one mode, the DC-DC converter provides the 3.5V VRE level required by the P54 processor. The linear regulator can provide 3.3V for peripheral components. The RC5035 can also be conÞgured to provide a 2.8V CPU core supply from the DC-DC converter and a 3.3V I/O supply from the linear regulator.

With the appropriate external components, the DC-DC converter can deliver load current as high as 10A and the linear regulator can provide 5A. The RC5035 DC-DC converter and the linear regulator can be set independently using two external resistors each to any value between 1.5V and 3.6V.The factory trimmed internal reference achieves tight tolerance voltage regulation on both outputs. Independent short circuit protection is also provided.