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AN-937 (v.Int)
Input: 5V/div
Output : 5V/div
Horiz: 500ns/div
Figure 15b: Waveforms of the circuit in Figure 21a
when loaded with 100nF
FILE: 01A-POL.DAT
VBATT1 5V/div
Output: 5V/div
Horiz: 20ms/div
File: 01-UV.dat
Figure 16. Start-up waveforms for the
circuit of Figure 15a.
Gate Voltage: 10V/div
C2 ripple voltage: 0.5V/div
Q1 drain voltage: 200V/div
Horiz: 5
µ
µs/div
File: GPS-1.plt
Figure 17b. Waveforms of the circuit in Figure
23a.C1 = 100 pF, R3 = 5.6 k, f = 50 kHz
Figure 17a. Drive supply developed from the drain voltage
+15V
D3
15V
15VRTN
C2
0.1
R3
D2
1N4148
C1
R2
100
D1
1N4148
Q1
IRF840
R1
10
Q2
IRF840
R4
R
G2
DRVRTN
DRIVE
VCC(300V)
20
30
40
50
60
70
80
90
100
0
1
2
3
Frequency (kHz)
Figure 18. Zener current (max output current)
for the circuit in Figure 23a.
Figure 19. Start-up voltage at 50 kHz
for the circuit in Figure 23a.
Horiz.: 500
µ
µs/div
File: GPS-3.PLT
C2 voltage: 5V/div.
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