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DN06024/D
May 2007, Rev. 0 www.onsemi.com 1
Design Note – DN06024/D
Universal AC 40 W Programmable Output
Device Application Input Voltage Output Power Topology I/O Isolation
NCP1217
Programmable AC-
DC Adapter
Universal
88-269 Vac
40 Watt Flyback 3 kV
Circuit Description
This programmable output voltage adapter is designed
around the NCP1217 PWM switcher. This flyback
converter operated in the DCM for the full range of output
to 44 watts. This permits the primary current limit to
function as the secondary power limit.
The adapter is designed to provide an output of 9 Vdc
nominal with no jumper connections. This gives the
system the security of a low voltage default output. A
single jumper may be installed in only one of the three
positions shown to program the output.
The current/power sense resistor section has resistors
R10 and R11 to permit “break-off” trimming options.
The schematic shows optional Y caps in pink for systems
with a three-wire power cord. The earth return provides
additional margin for applications that require more EMI
filtering or earth ground safety connection.
Key Features
y Constant power limit of 44 watts.
y Output voltage is programmed with jumpers
y 100 kHz Switchmode controller.
y Frequency dithering reduces EMI signature.
y Low standby power consumption.
Other Specifications
Output 1 Output 2 Output 3 Output 4
Output Voltage
(4 Possible Configurations)
+9 Vdc ±5% +12 Vdc ±5% +16 Vdc ±5% +24 Vdc ±5%
Ripple (50 MHz BW)
<90 mVpp <120 mVpp <160 mVpp <240 mVpp
Nominal Current
4.0 A 3.33 A 2.5 A 1.70 A
Max Current
4.5 A 3.38 A 3.0 A 1.70 A
Min Current
0 0 0 0
PFC (Yes/No)
NO
Minimum Efficiency
80% Target
Inrush Limiting / Fuse
80 A max / 1 A fuse
Operating Temp. Range
0 to +40° C
Cooling Method/Supply Orientation
Case Convection
Output Voltage Control
Adapter Program Plug
Others
Leakage Current: <3.5mA at 115VAC/60Hz and at 230VAC/50Hz (refer to EN60950)
OVP: 25% above the Output Voltage specified.
OCP: The Max Current is short circuit current trip point. The unit must be capable of supplying up to
and including the Max Current for 10 minutes. The Nominal Current is the maximum continuous
operating current.
