Universal AC input, Primary Side Regulation
AP3981B 12V-500mA EV2 Board User Guide
AP3981B EV2 Page 1 of 13 11
– 12 - 2019
Rev1.0 www.diodes.com
General Description
Based on Flyback topology, the Primary side
Regulated AP3981B EV board is designed to
serve as an example for High Efficiency, low
cost & less components consumer home
appliance systems. Also a 650V N MosFet is
integrated within control IC for easy fitting in a
flexible & small size power system design.
During the valley on operating & work at PFM
region the high efficiency and low standby
function can be achieved, by mean of using
multi-mode controlling skill the accurate constant
voltage and constant current can be easy meet.
Its output power is rated at 6W with 12V-0.5A. It
can meet DOE VI and CoC Tier 2 energy
efficiency requirement.
Key Features
90 ~264V
AC
input range
Using the Primary side control for eliminating the
Opto-coupler.
Multi-Mode
PFM
method
operations,
the
switching
frequency between 24kh ~80Khz.
With Valley on detection the switching stay at
Valley on region so that will improve power
converting efficiency & EMI performance, the
82% Efficiency can be reached at full load.
During the burst mode operation and Low start-
up operating quiescent currents the 75mW low
standby input power can be achieved.
Dynamic response is improved during work at
three mode operation as well as benefiting the
accurate constant voltage (CV) regulation &
constant current (CC) performance.
There is a Soft start during startup process.
Built-in Jittering Frequency function which is the
EMI emission can be improved
.
Internal Auto Recovery OCP, OVP, OLP, OTP
Power Protection, cycle by cycle current limit,
also with DC polarity protection
Built
–in Cable Compensation mode.
With a Brown out Protection.
Applications
Switching AC-DC Adaptor & Charger
Power home Appliances systems
The auxiliary Vcc power supply for bigger power
system.
Universal AC input PSR
12
V-
500m
A Power
Specifications (CV & CC mode)
Parameter
Value
Input Voltage
90 to 264V
AC
Input standby power
75mW
Main output Vo / Io
12V
– 500mA
Efficiency
~ 82.0%
Total Output Power
6W
Protections
OCP, OVP, OLP,OTP
XYZ Dimension
34 x 51 x 10 mm
ROHS Compliance
Yes
Evaluation Board Picture:
Figure 1:
Top View
Figure 2:
Bottom View