Power integrations TinySwitch-III Series User Manual

6
E
2/06
TNY274-280
Figure 12. Normal Power-Down Timing (without UV).
Figure 13. Slow Power-Down Timing with Optional External
(4 M
Ω) UV Resistor Connected to EN/UV Pin.
Figure 10. Power-Up with Optional External UV Resistor (4 MΩ)
Connected to EN/UV Pin.
Figure 11. Power-Up Without Optional External UV Resistor
Connected to EN/UV Pin.
PI-2661-082305
V
DRAI
N
V
EN
CLOCK
DC
DRAIN
I
MAX
Figure 9. Operation at Very Light Load.
At near maximum load, TinySwitch-III will conduct during
nearly 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 (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.
PI-2395-030801
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2.5 5
Time (s)
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400
300
0
100
200
V
DC-INPUT
V
DRAIN
0
1 2
Time (ms)
0
200
400
5
0
10
0
100
200
PI-2383-030801
V
DC-INPUT
V
BYPASS
V
DRAIN
PI-2381-1030801
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1 2
Time (ms)
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400
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DC-INPUT
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BYPASS
V
DRAIN
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.5 1
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V
DC-INPUT
V
DRAIN

Power integrations TinySwitch-III Series Specifications

General

Brand	Power integrations
Model	TinySwitch-III Series
Category	Switch
Language	English