Active-Semi
ACT8309/8310/8311
Rev PrA, 24-Jan-08
Advanced Product Information – All Information Subject to Change
1.5A, PWM Step-Down DC/DCs in TDFN
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
GENERAL DESCRIPTION
The patent-pending ACT8309/ACT8310/ACT8311
are current-mode, fixed-frequency PWM, synchro-
nous 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 requir-
ing 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 out-
put voltages that are programmable down to 1.2V.
Contact Active-Semi for custom fixed output voltage
availability.
SYSTEM BLOCK DIAGRAM
2.7V to 5.0V
ON
OFF
Power-OK
Output
Active-Semi
IN
SW
ACT8311
EN
FB
POK
GP G
VOUT
Up to 1.5A
Pb-free
Innovative Products. Active Solutions.
-1-
www.active-semi.com
Copyright © 2008 Active-Semi, Inc.