■
The adjustment of the rise time is possible by connecting C
SEQ
.
Fig.11.1.1
Example of
soft start circuitry
■
When the voltage is applied to the terminal SEQ , the output voltage tracks this voltage
until the output reaches the set-point voltage .
SEQ terminal voltage vs output voltage is calculated the following formula .
C
SEQ
[μF] = (0.284 ÷ Vo[V] - 0.06) × T[ms]
(Vo min
≦
Vo
≦
2.0V)
Vo min : 0.6V(only BRxS40) or 0.7V
C
SEQ
[μF] = (0.284 ÷ Vo[V] - 0.047) × T[ms]
(2.0
<
Vo
≦
3.63V only BRFS30)
Avoid SEQ terminal voltage is set below the set voltage output by Rtrim , the output voltage
dose not rise to set output voltage . Maximum applicable voltage of terminal SEQ is Vin .
When the function is not used , open terminal SEQ .
Fig.11.1.2
SEQ > Vout setting
Fig.11.1.3
SEQ < Vout setting
(not recommended)
BRFS/BRDS 11-1
11. Sequence
Applications manual
For BRFS/BRDS series