AN718 Datasheet: Powering The Pentium Vre With The Si9145 Voltage Mode Controlled PWM Converter





AN718 Powering The Pentium Vre With The Si9145 Voltage Mode Controlled PWM Converter Datasheet

Part Number AN718
Description Powering The Pentium Vre With The Si9145 Voltage Mode Controlled PWM Converter
Manufacture Vishay Intertechnology
Total Page 8 Pages
PDF Download Download AN718 Datasheet PDF

Features: AN718 Vishay Siliconix AN718 Powering t he Pentium™ VRE with the Si9145 Volta ge Mode Controlled PWM Converter BENEFI TS • First and only Intel-approved sw itching converter solution to provide s tatic and dynamic voltage regulation fo r the Pentium VRE microprocessor. • L ow cost • Efficiency greater than 89% at 7 A • Eliminates the need for hea t sinks • Supplies maximum currents r equired by P54C • High operating freq uency (recommended 375 kHz) allows use of the smallest possible inductors and capacitors, resulting in lowest voltage ripple and best transient response • Easily adjustable output voltage to me et the different specs of P54C family. • PCB layout available • Available in SO-16 surface-mount package The Si91 45BY consistently satisfies Pentium VRE voltage regulation limits within gener ous margins. Worst-case assumptions for voltage regulation, as provided by Int el, are displayed in Figure 2. REGULAT ION REQUIREMENTS FOR THE VRE PENTIUM CONVERTER The Pentium VRE microprocessor has b.

Keywords: AN718, datasheet, pdf, Vishay Intertechnology, Powering, The, Pentium, Vre, With, The, Si9145, Voltage, Mode, Controlled, PWM, Converter, stock, pinout, distributor, price, schematic, inventory, databook, Electronic, Components, Parameters, parts, cross reference, chip, Semiconductor, circuit, Electric, manual, substitute, Equivalent

AN718
Vishay Siliconix
AN718
Powering the Pentium™ VRE with the Si9145 Voltage Mode
Controlled PWM Converter
BENEFITS
• First and only Intel-approved switching converter solution to
provide static and dynamic voltage regulation for the
Pentium VRE microprocessor.
• Low cost
• Efficiency greater than 89% at 7 A
• Eliminates the need for heat sinks
• Supplies maximum currents required by P54C
• High operating frequency (recommended 375 kHz) allows
use of the smallest possible inductors and capacitors,
resulting in lowest voltage ripple and best transient
response
• Easily adjustable output voltage to meet the different specs
of P54C family.
• PCB layout available
• Available in SO-16 surface-mount package
A PROVEN SOLUTION FOR THE PENTIUM™
CONVERTER
Siliconix has developed the first and only Intel-approved
switching power supply solution for the Pentium VRE
microprocessor. Built on a leading-edge CBiC/D process, the
Si9145BY is the only voltage-mode controlled PWM IC
capable of switching up to 2 MHz and providing a 25-MHz
error amplifier. For the first time, a 100-kHz closed-loop
bandwidth switching converter can be designed to meet the
dynamic transient requirements of the Pentium
microprocessor, without adding numerous output capacitors.
The Si9145BY consistently satisfies Pentium VRE voltage
regulation limits within generous margins. Worst-case
assumptions for voltage regulation, as provided by Intel, are
displayed in Figure 2.
REGULATION REQUIREMENTS FOR THE VRE
PENTIUM CONVERTER
The Pentium VRE microprocessor has been designed to
operate faster and more efficiently than any of its
predecessors. To save power, a CPU clock has been
implemented with start/stop features, requiring an ultra-fast
response from the power supply. To obtain higher clock
speeds and to enhance manufacturing yields, the Pentium
requires specific output voltage levels with tight voltage
regulations (Figure 3). Within this stringent voltage regulation
limit, no overshoot or undershoot are permitted to exceed the
regulation limit, irrespective of their duration. Not surprisingly,
these new demands have overwhelmed the capabilities of
existing power supply designs based on conventional PWM
ICs.
Meeting the tight static and transient regulation demands of
the Pentium VRE microprocessor requires a certain amount of
decoupling capacitance both at the processor and at the
output of the power supply. Obviously, the greater the
decoupling capacitance, the easier it is to meet the transient
regulation. Since cost and space limit the amount of
capacitance one can use, Intel has recommended the use of
six 100-µF low-ESR tantalum capacitors and twenty-five 1-µF
ceramic capacitors.
FIGURE 1. Typical Application Circuit
Pentium™ is a trademark of Intel Corporation.
FaxBack 408-970-5600, request 70588
www.siliconix.com
FIGURE 2. Intel Measured Transient Response
1

                    
  






Index : 0  1  2  3   4  5  6  7   8  9  A  B   C  D  E  F   G  H  I  J   K  L  M  N   O  P  Q  R   S  T  U  V   W  X  Y  Z
@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)