NCP1000_06 Datasheet, PDF (13/14 Pages) ON Semiconductor – Integrated Off−Line Switching Regulator

NCP1000, NCP1001, NCP1002
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Hysteretic Regulation
Startup Circuit
V_CC Limiter
(Pin 1)
On Off On Off On Off On Off
I_start I_CC1 I_start I_CC2 I_start I_CC2 I_start I_CC1
35% 65%
Startup MOSFET
Duty Cycle
During Auto Restart
Power Switch
Circuit Voltage
(Pin 5)
Eight Cycles
Power Switch Circuit Duty Cycle During Auto Restart
5%
95%
Switching Disabled Switching
Startup
Switching Disabled Switching Switching Disabled Switching
Auto Restart Operation with Overloaded or Shorted Output
Figure 20. Auto Restart Operation Timing Diagram
8.6 V
7.5 V
0V
Flyback Voltage
Rectified Line Voltage
0V
APPLICATIONS INFORMATION
APPLICATION #1: Offline Converter Provides
5.0 V, 1.0 A Output for Small Electronic Equipment
ON Semiconductor’s NCP1000 series of offline converters
offers a low cost, high efficiency power source for low power,
electronic equipment. It serves the same function as small, line
frequency transformers, but with the added benefits of line and
load regulation, transient suppression, reduction in weight, and
operation across the universal input voltage range.
This kit provides a 5.0 V, 1.0 A output, which is derived from
an input source of 85 to 265 Vac, and 50 Hz to 60 Hz. This range
of input voltages will allow this circuit to function virtually
anywhere in the world without modification. The output is
regulated and current limited, and EMI filters are included on
both the input and output.
Converter Test Data
Parameter
Conditions
Line Regulation
85 v v Vin v 265 v
Load Regulation 0 A v lo v 1.0 A
Combined Line/
Load Regulation
85 v v Vin v 265 v
.09 A v lo v 1.0 A
Output Ripple
lo = 1.0 A
Input Power
Power Factor
Efficiency
V_in = 115 v, lo = 1.0 A
V_in = 220 v, lo = 1.0 A
V_in = 115 v, lo = 1.0 A
V_in = 220 v, lo = 1.0 A
V_in = 115 v, lo = 1.0 A
V_in = 220 v, lo = 1.0 A
Data
DVo = 6.0 mV
DVo = 8.0 mV
DVo = 10 mV
100 mV_pp
7.75 watts
7.88 watts
−.57
−.49
h = 66%
h = 64%
F1
Vin
C1
RS _{D1 − D4}
6.8
+
+
C2a C2b
R7
6.8
R1
L2 ^D5
R2
C6
C3
D6
5 V, 1 A
C7
R3
R4
p/o U2
C10
p/o U2
C5
C4
1
NCP
1000
C8
U3
R5
RETURN
C9
Figure 21. Wall Adapter Schematic
For additional information on this application, please order application note AND8019/D from the Literature Distribution Center or download
from our website at http://onsemi.com.
http://onsemi.com
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