S-8363B-I6T1U2 Datasheet, PDF (19/50 Pages) Seiko Instruments Inc – PWM/PFM SWITCHABLE SWITCHING REGULATOR

STEP-UP, SUPER-SMALL PACKAGE, 1.2 MHz PWM/PFM SWITCHABLE SWITCHING REGULATOR
Rev.2.0_01
S-8363 Series
2. Diode
Use an externally mounted that meets the following conditions.
• Low forward voltage (Schottky barrier diode or similar types)
• High switching speed
• Reverse withstand voltage of VOUT + spike voltage or more
• Rated current of IPK or more
3. Input capacitor (CIN) and output capacitor (COUT)
To improve efficiency, an input capacitor (CIN) lowers the power supply impedance and averages the input current.
Select CIN according to the impedance of the power supply used. The recommended capacitance is 1 μF or more
for the S-8363 Series.
An output capacitor (COUT), which is used to smooth the output voltage, requires a capacitance larger than that of
the step-down type because the current is intermittently supplied from the input to the output side in the step-up
type. When the output voltage is low or the load current is large, enlarging an output capacitance value is required.
Moreover, when the output voltage is high, connecting a 0.1 μF ceramic capacitor in parallel is required. Mount
near a VOUT pin as possible.
The indication of an output capacitor to the setting value of VOUT voltage is shown in the table 10. Perform thorough
evaluation using an actual application to set the constant when selecting parts.
A ceramic capacitor can be used for both the input and output.
Table 10 Recommended Output Capacitance
VOUT voltage
< 2.5 V
2.5 V to 4.0 V
4.0 V <
Output capacitor (COUT)
10 μF × 2
10 μF
10 μF + 0.1 μF
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