NCP1011AP130 ON Semiconductor, NCP1011AP130 Datasheet - Page 12

• Manufacturer Part Number: NCP1011AP130
• Description: IC OFFLINE SWIT SMPS CM OVP 8DIP
• Manufacturer: ON Semiconductor
• Type: Self-Supplied Monolithic Switcherr

Specifications of NCP1011AP130

• Output Isolation: Isolated
• Frequency Range: 117 ~ 143kHz
• Voltage - Input: 8.5 ~ 10 V
• Voltage - Output: 700V
• Power (watts): 19W
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 8-DIP (0.300", 7.62mm), 7 Leads
• Input Voltage Range: - 0.3 V to + 10 V
• Mounting Style: Through Hole
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Lowering the Standby Power with Skip- -Cycle
power by skipping unwanted cycles at light loads.
However, the recurrent frequency in skip often enters the
audible range and a high peak current obviously generates
acoustic noise in the transformer. The noise takes its origins
in the resonance of the transformer mechanical structure
Skip- -cycle offers an efficient way to reduce the standby
Figure 18. A more detailed view of the NCP101X offers better insight on how to
Permanent
Figure 19. The burst frequency becomes so low that it is difficult to keep
Latch
Vclamp = 8.7 V typ.
VCC
VCC
ON
OFF
= 8.5 V
= 7.5 V
an adequate level on the auxiliary V
+
+
properly wire an auxiliary winding.
+
--
--
+
>30 ms
--
+
http://onsemi.com
+
12
I > 7.4m
(Typ.)
Startup Source
Ground
which is excited by the skipping pulses. A possible
solution, successfully implemented in the NCP1200 series,
also authorizes skip- -cycle but only when the power
demand has dropped below a given level. At this time, the
peak current is reduced and no noise can be heard.
Figure 20 pictures the peak current evolution of the
NCP101X entering standby.
V
CC
Drain
+
CVcc
Rlimit
CC
. . .
+
Caux
D1
Laux