1. FAN5358 2MHz, 500mA, SC70 Synchronous Buck Regulator
Product Guide
Peter Khairolomour, Aug 11th 2010

2. What is the FAN5358?
FAN5358 is a 2MHz 500mA fixed output voltage step-down converter
Vin: 2.7V – 5.5V
Vout: 1.0V, 1.2V, 1.3V, 1.8V
2MHz Switching frequency
500mA Output current

3. Power in → Power out! Input sources Output loads:
Vin: 2.7V – 5.5V
Output loads:
Vout: 1.0V, 1.2V, 1.3V, 1.8V
USB Power 4.5V – 5.5V
Memory ICs (Flash, SDRAM)
Digital Asics
DC supply
FPGAs
Microcontroller/processor cores
Single cell Li-ion
FAN5358
Digital Signal Processors (DSP)
3 battery cells
Low Voltage LDOs
High Voltage regulator

4. FAN5358 2MHz 500mA SC70 step-down DC/DC
Features
2MHz Variable-Frequency Operation
500mA Output Current
24µA Typical Quiescent Current
VOUT = 1.0V, 1.2V, 1.3V, 1.8V
Up to 90% Efficiency
L = 2.2uH
CIN = 2.2μF
COUT = 4.7μF
2.7V to 5.5V Input Voltage Range
Synchronous Operation
Soft-Start Capability
UVLO, TSD, and SCP Protection
SC70-6
Applications
DMB, Mutimedia, Application processors
Cell Phones, Smart-Phones
WLAN DC-DC Converter Modules
PDA, DSC, PMP, and MP3 Players
Schedule
Samples: NOW(1.0, 1.2, 1.8V)
Production: Jun 2009 (1.8V)
pin-to-pin with MAX8640Y but with higher efficiency and better transient response

5. Efficiency Comparison
Both solutions are pin-to-pin compatible

6. Two type of loads: Digital and Analog
Before diving into FAN5358 product details it is important to understand that there are two major point of load categories in portable applications
Digital loads
application processors
baseband processors
memory
digital TV processors
GPS processors
graphics processors
I/O rails
Analog loads
audio amplifiers
RF amplifiers
camera sensors
PLL/FLL/VCO
GPS receivers
FAN5358 is targeted towards digital loads

7. Digital vs. Analog loads
Digital Loads…
Because of the inherent binary nature of digital loads, they are not as sensitive to power supply behavior such as ripple noise, thermal noise, or noise interference.
They have fast dynamics as the application load can vary quickly and substantially so parameters such as power supply transient response and Iq during standby become critical
They operate at low voltages due to fine geometries used in core processors. In addition, power is reduced by operating off lower voltage rails. Typical range is 1V to 1.8V.
Analog Loads…
Because of the inherent sensitive nature of analog loads, noise issues that were not so much a concern for digital loads can now create problems
ripple and noise feed through are typically less tolerable for sensitive analog loads
analog loads typically do not share power supply inputs in order to preserve signal integrity
each analog IC may have different voltage levels optimized for performance and tend to operate at a higher voltage and lower current than digital ICs.

8. Many digital loads in cell phones!
BaseBand Processor (BB)
Keyboard controller
Bluetooth transceiver with baseband processor
Graphics Processing Unit (GPU)
Digital Base Band Processor with Main Central Processor (CPU) and Digital Signal Processor (DSP)
Image Sensor Processor (ISP)

9. Ultra-portables
Example: Media Player

10. Computer accessories
Example: Access card

11. Computer peripherals:
Example: Printer

12. Industrial
Example: Bar Code Scanner

13. Medical
Example: Electronic Stethoscope

14. Instrumentation
Example: National Instruments Data Acquisition card (Labview)

15. FAN5358 Value Proposition…
SC70 package easy to pick and place
Low cost total solution
High performance in terms of efficiency and mode transition smoothness. The former extends battery life and the latter generates less system noise.

16. Design-In support FAN5358 Datasheet
FAN5358 Product Overview
Evaluation Boards
Request via Sales Center or contact product line
Samples
Available from samples warehouse or contact product line

17. Contacts Marketing contacts Application support
Cell phones and data cards
Peter Khairolomour
All other customers
Stephen Stella
Application support
George Petre

18. Follow us on Twitter twitter.com/fairchildSemi
View product and company videos, listen to podcasts and comment on our
Visit us on