A Product Line of
LOW-POWER OFF-LINE PRIMARY SIDE REGULATION CONTROLLER
The AP3771 is a high performance AC/DC power supply controller for
battery charger and adapter applications. The device uses Pulse
Frequency Modulation (PFM) method to build discontinuous
conduction mode (DCM) flyback power supplies.
The AP3771 provides accurate constant voltage, constant current
(CV/CC) regulation without requiring an opto-coupler and the
secondary control circuitry. It also eliminates the need of loop
compensation circuitry while maintaining good stability. The AP3771
can achieve excellent regulation and high average efficiency, yet
meets no-load consumption less than 30mW. It can also achieve
excellent dynamic performance while maintaining 30mW standby
power with AP4340.
Pin 1 Mark
The AP3771 has a built-in fixed cable voltage drop compensation
function. The cable compensation voltage is set as 7% and 3% of the
rated output voltage. It also has an adjustable built-in line
compensation function to achieve tight CC.
The AP3771 drives MOSFET to achieve the high switching frequency
and high efficiency.
The AP3771 is available in SOT26 package.
Adapters/Chargers for Cell/Cordless Phones, PDAs, MP3 and
Other Portable Devices
Standby and Auxiliary Power Supplies
Primary Side Control for Tight Constant Current and Constant
30mW No-load Input Power
Excellent Dynamic Performance with AP4340 (For 5V
Proprietary Adjustable Line Compensation for CC Variation
Constant and Built-in 7% and 3% Voltage Drop Compensation
Enhanced Audio Noise Suppression
Open Circuit Protection
Over Voltage Protection
Short Circuit Protection
Totally Lead-free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
Document number: DS37281 Rev. 1 - 2
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© Diodes Incorporated