SP6659 Datasheet, PDF (1/10 Pages) Sipex Corporation – 1.5MHz, 600mA Synchronous Buck Regulator

®
Preliminary
SP6659
1.5MHz, 600mA Synchronous Buck Regulator
FEATURES
■ 94% Efficiency Possible
■ 600mA Output Current at V_IN = 3V
■ 2.5V to 5.5V Input Voltage Range
■ 1.5MHz constant frequency operation
■ No Schottky Diode Required
■ Output Voltages as low as 0.6V
■ Slope Compensated Current Mode
Operation for Excellent Line and Load
Transient Response
■ 100 % Duty Cycle in LDO Mode
■ <1µA Shutdown Current, Quiescent
Current of 300 µA
■ Over-temperature protected
■ Offered in Low Profile TSOT-23
package
VFB
VIN
VOUT
VIN
5
4
5
4
SP6659
5 Pin TSOT-23
SP6659
5 Pin TSOT-23
1
2
3
RUN
GND
SW
Adjustable
1
2
3
RUN
GND
SW
Fixed
Now Available in Lead Free Packaging
APPLICATIONS
■ Cell Phones
■ Wireless and DSL Modems
■ DSC's
■ Portable Instruments
DESCRIPTION
The SP6659 is a 600mA synchronous buck regulator using a constant frequency, current mode
architecture. The output voltage can be programmed using an external resistor divider. The 2.5V
to 5.5V input voltage range is ideal for portable applications that use a Li-Ion battery. Switching
frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and
capacitors. The internal synchronous switch increases efficiency and eliminates the need for an
external Schottky diode. The output voltage can be programmed using an external resistor
divider. Low output voltages are easily supported with the 0.6V feedback reference voltage. The
SP6659 is available in a low profile 5 pin TSOT-23 package.
TYPICAL APPLICATION SCHEMATICS
V _IN
4.7µF
Ceramic
®
SW
4
3
SP6659
RUN
1
V _FB
5
2.2µH
R2
2
R1
GND
V _OUT
V _IN
C2
22pF
10µF
Ceramic
4.7µF
Ceramic
®
4 SP6659 3 ^SW
2.2µH
RUN 1
5 ^VOUT
2
GND
Adjustable
Fixed
V _OUT
10µF
Ceramic
Date: 07/20/05
SP6659 1.5MHz, 600mA Synchronous Buck Regulator
1
© Copyright 2005 Sipex Corporation