NCP1239
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27
Figure 46.
+
−
IN
2
3
Cbulk
47uF
IC = 40
Bload
Current
VBulk
V(CMP) > 3, 35/V (bulk) : 0
bulk
Rupper
2.4Meg
Rlower
10k
Cfil
220n
+
−
5
Bbrown
Voltage
cmp
BrownOut
V(CMP) > 3, 250m : 500m
V1
B1
Voltage
line
V2
timing
V(line)*V(timing)
Vline
bulk
V2 timing 0 PWL 0 0.2 3s 1 7s 1 10s 0.2
V1 line 0 SIN 0 150 50
PSpice:
EBbrown Value = { IF ( V(CMP) > 3, 250m, 0) }
PSpice:
EBload Value = { IF ( V(CMP)>3, 35/V(bulk), 0) }
A simple simulation configuration helps to tailor the right value for Cfil
Figure 47.
Typical signals obtained from the simulator
8.156
8.175
8.195
8.215
8.235
0
4.0
8.0
12.0
16.0
−200
−100
0
100
200
Turn−off voltage occurs at:
VinRMS = 72.3 volts
Vbrown−out
