
9. REFERENCE: EXTERNAL CONNECTION EXAMPLES
S1F76540M0C Series Technical Manual
EPSON
31
(Rev.1.1)
Power-off method
Set the POFF2X pin to level LOW (VI); all circuits will be turned off.
For double boosting:
When performing double boosting, delete C2 and D1 shown in Figure 9.13, and connect the D2 anode
(positive pole) side to V
DD
.
Output voltage
In the positive voltage conversion, the diode characteristics directly affect the boosting characteristics.
Especially using the VF pin (forward voltage lowering) in a diode causes the boosting output voltage to be
reduced. In the example shown in Figure 9.11, three diodes are used; therefore, be sure to drop the voltage
by 3
×
VF as shown in Figure 9.12. The boosting power voltage is indicated in the following expression.
|
VO’
|
When increasing
|
VO’
|
, use a diode with the lower VF value.
|
VO’
|
= 3×
|
VI
|
-3×VF
・・・・・・・・
Expression (9.4)
Precautions
(1) Input and output current conditions
To keep the input and output current ratings, take care so that the input current does not exceed the
rating.
(2) Input voltage conditions
For positive voltage conversion, the input voltage rating is equal to for the negative double-boosting.
(See Table 7.1.)
Other setting conditions
(1) When using the high output mode
Connect the FC pin to VI.