General Description

SY8859 is a high efficient 1.0MHz synchronous step

down DC/DC regulator capable of delivering up to 3A

output current. The SY8859 can operate over a wide

input voltage range from 2.7V to 5.5V and integrates

main switch and synchronous switch with very low

RDS(ON) to minimize the conduction loss.

The low output voltage ripple, the small external

inductor and the capacitor sizes are achieved with

1.0MHz switching frequency.

Features

• Low RDS(ON) for Internal Switches (Top/Bottom)

85mΩ /50mΩ

• 2.7~5.5V Input Voltage Range

• 55µA Low Quiescent Current

• Ultra Fast Load Transient Speed

• High Switching Frequency 1.0MHz Minimizes

the External Components

• Internal Soft-start Limits the Inrush Current

• Reliable Short Circuit Protection

• Output Auto Discharge Function

• RoHS Compliant and Halogen Free

• Compact Package: QFN1.5×1.5-7

Applications

• Smart Phone

• LCD TV

• Set Top Box

• Mini-Notebook PC

• Access Point Router