Power for Pentium Processors; Meeting VRE Requirements (AN63)
Application note detailing power supply designs for Pentium and Pentium VRE processors using LTC1266 switching controllers and LT1584 linear regulators.
Overview
This application note provides design solutions for meeting the stringent power requirements of Pentium and Pentium VRE processors. It focuses on the LTC1266 synchronous buck regulator for high-efficiency switching and the LT1584 for fast-transient linear regulation. The document addresses challenges including 3.5V VRE voltage tolerances and extreme load transients from 200mA to 4A within 20ns. Key circuits include a high-precision switcher utilizing the LT1431 shunt regulator for enhanced DC accuracy and remote sensing. Technical guidance is provided for decoupling capacitor selection, PCB layout to minimize inductance, and input capacitance to stabilize the 5V supply during transients.
Use Cases
- Pentium processor power supply
- VRE microprocessor voltage regulation
- 5V to 3.3V DC-DC conversion
- High-transient load regulation
- Desktop PC motherboard power design
Topics
Referenced Parts
LT1431
Linear Technology
The LT1431 however, does have a sufficiently accurate reference
LT1584
Linear Technology
LT1584 linear regulator to provide power
LT1584CT
Linear Technology
U1 LT1584CT
LTC1266
Linear Technology
new LTC1266 synchronous buck regulator control chip
MBR120T3
Motorola
D1, D2: MBR120T3
Si4410
Siliconix
FOR 10A USE Si4410
Si9410
Siliconix
FOR 5A OUTPUT USE Si9410
10V
AVX
minimum, use four pieces of a 100μF, 10V AVX type TPS
| MBRS320T3 | Motorola | D3 MBRS320T3 |
| 627V100 | BI Technologies | PRECISION DIVIDER NETWORK (BI TECH. 627V100) |
| LT1431 | Linear Technology | The LT1431 however, does have a sufficiently accurate reference |
| LT1584 | Linear Technology | LT1584 linear regulator to provide power |
| LT1584CT | Linear Technology | U1 LT1584CT |
| LTC1266 | Linear Technology | new LTC1266 synchronous buck regulator control chip |
| MBR120T3 | Motorola | D1, D2: MBR120T3 |
| Si4410 | Siliconix | FOR 10A USE Si4410 |
| Si9410 | Siliconix | FOR 5A OUTPUT USE Si9410 |
| 10V | AVX | minimum, use four pieces of a 100μF, 10V AVX type TPS |