S-8550AA-M5T1X Datasheet, PDF (1/31 Pages) Seiko Instruments Inc – RECTIFICATION, PWM CONTROL SWITCHING REGULATORS

S-8550 Series
www.sii-ic.com
STEP-DOWN, BUILT-IN FET, SYNCHRONOUS
RECTIFICATION, PWM CONTROL SWITCHING REGULATORS
© SII Semiconductor Corporation, 2007-2015
Rev.5.0_01
The S-8550 Series is a CMOS synchronous rectification step-down switching regulator which mainly consists of a
reference voltage circuit, an oscillator, an error amplifier, a phase compensation circuit, a PWM controller, an under
voltage lockout circuit (UVLO), a current limit circuit, and a power MOS FET. The oscillation frequency is high at 1.2 MHz,
so a high efficiency, large output current, step-down switching regulator can be achieved by using small external parts.
The built-in synchronous rectification circuit makes achieving high efficiency easier compared with conventional step-down
switching regulators. A ceramic capacitor can be used as an output capacitor. High-density mounting is supported by
adopting packages small SOT-23-5 and super-small and thin SNT-8A.
 Features
• Oscillation frequency:
1.2 MHz
• Input voltage range:
2.0 V to 5.5 V
• Output voltage range:
Arbitrarily settable by external output voltage setting resistor
• Output current:
600 mA
• Reference voltage:
0.6 V ±2.0%
• Efficiency:
92%
• Soft-start function:
1 ms typ.
• Shutdown function:
Shutdown current consumption : 1.0 μA max.
• Built-in current limit circuit
• Pch power MOS FET on-resistance:
0.4 Ω typ.
• Nch power MOS FET on-resistance:
0.3 Ω typ.
• Constant continuous mode operation (no light load mode)
• Lead-free, Sn 100%, halogen-free^*1
*1. Refer to “ Product Name Structure” for details.
 Applications
• Mobile devices, such as mobile phones, Bluetooth devices, wireless devices, digital audio players, digital still
cameras, portable DVD players, and portable CD players
 Packages
• SOT-23-5
• SNT-8A
1