ncp1282 ON Semiconductor, ncp1282 Datasheet - Page 12

• Manufacturer Part Number: ncp1282
• Description: High-performance Active Clamp/reset Pwm Controller Featuring Hv Start-up
• Manufacturer: ON Semiconductor

500
450
400
350
300
250
200
150
100
90
85
80
75
70
65
60
55
50
45
40
900
800
700
600
500
400
300
200
100
50
0
-50
0
10
0
C
C
-25
T
T
= 470 pF
R
= 150 pF
R
R
T
Figure 24. Oscillator Frequency
T
TRAILING
T
Figure 28. Overlap Time Delay
T
= 11.8 kW, C
80
30
= 15.8 kW, C
J
= 20 kW, C
, JUNCTION TEMPERATURE (°C)
vs. Junction Temperature
0
R
Figure 26. Duty Cycle
C
R
D
vs. Timing Resistor
vs. Delay Resistor
T
T
, DELAY RESISTOR (kW)
, TIMING RESISTOR (kW)
= 220 pF
25
LEADING
160
50
T
T
T
= 150 pF
= 470 pF
= 220 pF
50
240
70
75
V
R
100
AUX
V
T
D
AUX
J
= 69.8 kW
V
T
320
= 25°C
AUX
J
= 12 V
90
= 25°C
= 12 V
125
= 12 V
http://onsemi.com
150
400
NCP1282
110
12
25
24
23
22
21
20
19
18
17
16
15
-50
400
350
300
250
200
150
100
Figure 27. Soft-Start/Stop Charge and Discharge
50
90
85
80
75
70
65
60
55
50
45
40
0
-50
10
-25
C
T
Currents vs. Junction Temperature
T
= 470 pF
-25
J
, JUNCTION TEMPERATURE (°C)
0
C
30
T
Figure 29. Overlap Time Delay
T
DISCHARGE (V
t
t
t
CHARGE
t
t
t
D(lead)
D(lead)
D(lead)
J
D(trail)
D(trail)
D(trail)
= 150 pF
, JUNCTION TEMPERATURE (°C)
vs. Junction Temperature
0
25
R
T
Figure 25. Duty Cycle
C
, TIMING RESISTOR (kW)
vs. Timing Resistor
T
25
= 220 pF
50
50
UVOV
50
75
= 0 V)
70
75
V
100
AUX
V
T
R
V
AUX
J
D
= 12 V
100
R
AUX
R
= 25°C
125
= 69.8 kW
D
D
90
R
= 12 V
= 69.8 kW
= 200 kW
D
= 12 V
= 20 kW
125
150
150
140
130
120
110
100
90
80
70
60
50
110
150