TC78B002FNG
2013-10-17
19
<PWM change during soft switching>
Soft switching after conducting phase switch:
It changes gradually from 4% to 100% of output PWM duty determined by the voltage of VSP pin. Its number
of steps is 16 in maximum.
Soft switching before conducting phase switch:
It changes gradually from 100% to 4% of output PWM duty determined by the voltage of VSP pin. Its number
of steps is 16 in maximum.
In case the term of soft switching operation is 22.5° or less, number of steps is less than16 in the soft switching
term.
The relation of steps of soft switching and the output PWM duty ratio is shown below.
Step
Output ratio (%)
Step
Output ratio (%)
Step
Output ratio (%)
1
4
7
59
13
94
2
14
8
67
14
97
3
25
9
74
15
99
4
34
10
80
16
100
5
42
11
86
6
52
12
91
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Term of soft switching operation
