general description
the patent-pending act8309/act8310/act8311
are current-mode, fixed-frequency pwm, synchronous
step-down dc/dc converters that are capable
of delivering 1.5a with efficiency of up to 95%.
these devices operate with a fixed frequency of
1.35mhz, minimizing noise in sensitive equipment
as well as optimizing both efficiency and component
size and cost.
these devices feature very low-resistance power
mosfet and 100% duty cycle operation, making
them ideal choices for portable applications requiring
a 3.0v or 3.3v rail to be generated from a li+
battery.
the act8311 is capable of supplying up to 1.5a of
output current, while the act8309 and act8310
are capable of supplying up to 900ma and 1.2a,
respectively. all three devices have adjustable output
voltages that are programmable down to 1.2v.
contact active-semi for custom fixed output voltage
availability.

features
• multiple patents pending
• up to 95% high efficiency
• up to 1.5a guaranteed output current (act8311)
• 1.35mhz constant frequency operation
• internal synchronous rectifier eliminates
schottky diode
• act8309: up to 900ma
• act8310: up to 1.2a
• act8311: up to 1.5a
• 100% duty cycle low-dropout operation
• 0.1μa shutdown current
• small tdfn33-8 package
− rohs-compliant
• independent enable/disable control
• minimal external components
applications
• wireless handhelds
• portable devices
• gps/pnd equipment

www.szkxw.com