TNY274_09 POWERINT [Power Integrations, Inc.], TNY274_09 Datasheet - Page 6

• Manufacturer Part Number: TNY274_09
• Description: Energy-Effi cient, Off-Line Switcher With Enhanced Flexibility and Extended Power Range
• Manufacturer: POWERINT [Power Integrations, Inc.]

Rev. I 01/09
all of its clock cycles (Figure 6). At slightly lower load, it will
“skip” additional cycles in order to maintain voltage regulation at
the power supply output (Figure 7). At medium loads, cycles
will be skipped and the current limit will be reduced (Figure 8).
At very light loads, the current limit will be reduced even further
At near maximum load, TinySwitch-III will conduct during nearly
200
100
400
200
Figure 10. Power Up with Optional External UV Resistor (4 MΩ)
200
100
400
300
200
100
10
Figure 12. Normal Power Down Timing (without UV).
0
5
0
0
0
0
6
0
0
V
V
V
Connected to EN/UV Pin.
DC-INPUT
DRAIN
BYPASS
TNY274-280
Time (ms)
Time (s)
.5
1
V
V
DC-INPUT
DRAIN
2
1
(Figure 9). Only a small percentage of cycles will occur to satisfy
the power consumption of the power supply.
The response time of the ON/OFF control scheme is very fast
compared to PWM control. This provides tight regulation and
excellent transient response.
200
100
Figure 13. Slow Power Down Timing with Optional External (4 MΩ) UV Resistor
200
100
Figure 11. Power Up Without Optional External UV Resistor
400
200
400
300
200
100
10
0
5
0
0
0
0
0
0
V
Connected to EN/UV Pin.
Connected to EN/UV Pin.
V
V
DC-INPUT
DRAIN
BYPASS
Time (ms)
Time (s)
2.5
1
V
DC-INPUT
V
DRAIN
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