REGULATOR CONTROLLER. S-8533 Datasheet
© ABLIC Inc., 2002-2010
STEP-DOWN, SYNCHRONOUS PWM CONTROL
SWITCHING REGULATOR CONTROLLER
The S-8533 Series is a synchronous PWM control CMOS step-down switching regulator controller that includes a reference
voltage source, synchronous circuit, oscillation circuit, error amplifier, phase compensation circuit, and PWM controller.
An efficient step-down switching regulator can be realized simply by adding external P-channel and N-channel power MOS
FETs, one coil, and three capacitors.
Since the oscillation frequency is a high 300 kHz, the S-8533 can be used to configure a high efficiency step-down switching
regulator capable of driving high output current using small external parts and a 3 to 10% increase in efficiency is obtained
compared to conventional step-down switching regulators.
The 8-Pin TSSOP package and high oscillation frequency make the S-8533 ideal as the main power supply for portable
Synchronous rectification system realizing high efficiency (typ. 94%)
Use at maximum duty ratio = 100% and use of a battery up to maximum life is possible by using P-channel and N-
channel power MOS FETs externally.
Oscillation frequency : 300 kHz typ.
Input voltage :
2.7 to 16.0 V
Output voltage :
1.3 to 6.0 V, selectable in 0.1 V steps
Output voltage accuracy : 2.0%
Soft-start function set by an external capacitor (CSS)
Lead-free, Sn 100%, halogen-free*1
*1. Refer to “ Product Name Structure” for details.
Constant voltage power supply for hard disks and DVD drivers
Power supplies for portable devices, such as digital cameras, PDAs, electronic organizers, and cellular phones
Main or sub power supply for notebook PCs and peripherals
Constant voltage power supply for cameras, video equipment, and communication equipment
STEP-DOWN, SYNCHRONOUS PWM CONTROL SWITCHING REGULATOR CONTROLLER
PWM control circuit
source with soft start
Remark All the diodes in the figure are parasitic diodes.
ON / OFF