ACT334
Rev 2, 14-Nov-12
TM
High Performance ActivePSR Primary Switching Regulator
over temperature conditions.
FEATURES
TM
The ACT334 ActivePSR is optimized for high
Ultra Low Standby Power < 30mW
performance, cost-sensitive applications, and
Patented Primary Side Regulation
utilizes Active-Semis proprietary primary-side
Technology
feedback architecture to provide accurate constant
voltage, constant current (CV/CC) regulation
Suitable Operation Frequency up to 85kHZ
without the need of an opto-coupler or reference
Proprietary Fast Startup Circuit
device. Integrated line and primary inductance
compensation circuitry provides accurate constant
Integrated Line and Primary Inductance
current operation despite wide variations in line
Compensation
voltage and primary inductance. Integrated output
Integrated Programmable Output Cord
cord resistance compensation further enhances
Resistance Compensation
output accuracy. The ACT334 achieves excellent
regulation and transient response, yet requires less
Line Under-Voltage, Output Over-Voltage,
than 30mW of standby power.
Output Short-Circuit and Over-Temperature
Protection
The ACT334 is optimized for compact size 2W to
Complies with all Global Energy Efficiency 6W charger applications. It is available in space-
and CEC Average Efficiency Standards saving 6 pin SOT23-6 package.
Adjustable Power from 2W to 6W
Figure 1:
Minimum External Components
Simplified Application Circuit
Tiny SOT23-6 Package
APPLICATIONS
Chargers for Cell Phones, PDAs, MP3,
Portable Media Players, DSCs, and Other
Portable Devices and Appliances
RCC Adapter Replacements
Linear Adapter Replacements
Standby and Auxiliary Supplies
GENERAL DESCRIPTION
The ACT334 belongs to the high performance
TM
patented ActivePSR Family of Universal-input
AC/DC off-line controllers for battery charger and
adapter applications. It is designed for flyback
topology working in discontinuous conduction mode
(DCM). The ACT334 meets all of the global energy
efficiency regulations (CEC, European Blue Angel,
and US Energy Star standards) while using very
few external components.
The ACT334 ensures safe operation with complete
protection against all fault conditions. Built-in
protection circuitry is provided for output short-
circuit, output over-voltage, line under-voltage, and
TM
Innovative Power - 1 - www.active-semi.com
Copyright 2012 Active-Semi, Inc.
ACT334
Rev 2, 14-NoRev 2, 14-Nov-12v-12
ORDERING INFORMATION
PACKING
PART NUMBER TEMPERATURE RANGE PACKAGE PINS TOP MARK
METHOD
ACT334US-T -40C to 85C SOT23-6 6 TAPE & REEL FSTA
PIN CONFIGURATION
SOT23-6
ACT334US-T
PIN DESCRIPTIONS
PIN NAME DESCRIPTION
Switch Drive. Switch node for the external NPN transistor. Connect this pin to the external
1 SW
power NPNs emitter. This pin also supplies current to VDD during startup.
2 GND Ground.
3 BD Base Drive. Base driver for the external NPN transistor.
Power Supply. This pin provides bias power for the IC during startup and steady state
4 VDD
operation.
5 FB Feedback Pin. Connect this pin to a resistor divider network from the auxiliary winding.
Current Sense Pin. Connect an external resistor (R ) between this pin and ground to set
CS
6 CS peak current limit for the primary switch. The peak current limit is set by (0.396V 0.9) /
R . For more detailed information, see Application Information.
CS
TM
Innovative Power - 2 - www.active-semi.com
Copyright 2012 Active-Semi, Inc.