A Product Line of
GREEN MODE PWM CONTROLLER
The AP3125B is a current mode PWM controller which is optimized
for high performance, low standby power and cost effective offline
The PWM switching frequency at normal operation is internally fixed
(about 65kHz). In middle load, the IC will enter green mode to
improve system efficiency with the help of frequency foldback. A
minimum switching frequency (about 20kHz) is set to avoid the
audible noise. In no load or light load, the IC will enter the burst mode
to minimize standby power. Furthermore, the frequency dithering
function is built-in to reduce EMI emission.
Internal slope compensation allows more stable Peak-Current Mode
control over wide range of input voltage and load conditions. Internal
line compensation ensures constant output power limit over entire
universal line voltage range.
Comprehensive protection features are included, such as cycle-by-
cycle current limit (OCP), VCC Over Voltage Protection (VOVP),
internal OTP, Over Load Protection (OLP) and pins’ fault protection.
Built-in Brownout (BNO) and Line Over Voltage Protection (LOVP)
are also integrated in AP3125B.
Pin 1 Mark
Very Low Start-up Current
Current Mode Control
Non-audible-noise Green-mode Control
Internal Slope Compensation
Soft Start During Startup Process
Frequency Fold Back for High Average Efficiency
Secondary Winding Short Protection with FOCP
Soft Switching for Reducing EMI
VCC Maintain Mode
Brownout Protection (BNO)
Line Over Voltage Protection (LOVP)
Useful Pin Fault Protection:
SENSE Pin Floating
SENSE Pin Short to Ground
Comprehensive System Protection Feature:
VCC Over Voltage Protection (VOVP)
Over Load Protection (OLP)
Mini Size with Packages
Pin to Pin Compatible with AP3105NA/NV/NL/NR
Totally Lead-free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
Switching AC-DC Adapter/Charger
ATX/BTX Auxiliary Power
Set-top Box (STB) Power Supply
Open Frame Switching Power Supply
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: DS36659 Rev. 3 - 2
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