ST1S14 STMicroelectronics, ST1S14 Datasheet - Page 13

• Manufacturer Part Number: ST1S14
• Description: Up to 3 A step down switching regulator
• Manufacturer: STMicroelectronics

ST1S14
5.2
Minimum output voltage over V
The minimum regulated output voltage at a given input voltage is limited by the minimum
conduction time of the power element, that is 90nsec typical for the ST1S14:
Equation 1
which is plotted in
minimum V
Figure 8.
Figure 8
switching activity and a predictable output voltage ripple.
The regulator can anyway regulate the minimum input voltage over the entire input voltage
range but, given the 90ns minimum conduction time of the power element, it will skip some
pulses to keep the output voltage in regulation when
This operation is not recommended at the nominal input voltage of the application mainly
because it affects the output voltage ripple, but it is generally accepted during a line
transient event.
shows the minimum output voltage over input voltage range to have constant
O_SET
V
O_MIN
at low V
Figure
V
O_MIN
over input voltage range
14. The reference of the embedded error amplifier (1.22V) sets the
(
IN
V
IN
.
)
Doc ID 17977 Rev 1
=
V
IN
⋅
D
MIN
=
V
IN
IN
⋅
range
T
--------------------- -
ON_MIN
T
Equation 1
SW
Additional features and limitations
=
V
IN
is not satisfied.
⋅
------------------
1.18μs
90ns
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