Increasing S6BP202A Rated Output Current under Low Input Voltage Condition – KBA226161

Version 3

    Author: AtsushiT_61           Version: **

     

    Translation - Japanese: 低入力電圧条件下でのS6BP202A定格出力電流の増加 – KBA226161 - Community Translated (JA)

     

    Question:

    How can the rated output current of S6BP202A be increased under low input voltage condition?

     

    Answer:

    Lower the switching frequency to increase S6BP202A’s rated output current at low input voltage.

    Figure 1 shows the IVOUT vs VVIN graph for the default switching frequency of 2.1 MHz. For example, the rated output current is approximately 0.7 A when VVIN = 3.5V (Ta=+25°C).

     

    Figure 1. IVOUT vs VVIN Graph

    By setting the switching frequency to 200 kHz, the rated output current is increased to 1.2 A when VVIN = 3.5V (Ta=+25°C), as shown in Figure 2.

     

    Figure 2. IVOUT vs VVIN Graph

    To set the switching frequency to 200 kHz, use the following component values:

    • Setting Resistor (RT) = 270 kΩ
    • Inductor (L) = 22 μH (CLF12577NIT-220M-D)
    • Input Capacitor (CIN) = 10 μF
    • Select either of the option for Output Capacitor (COUT):

     

          Option 1

    Item

    Amount

    Ceramic CGA6P1X7R1C226M250AC

    8

     

    Option 2

    Item

    Amount

    Polymer electrolytic HHXD160ARA151MF80G

    1

    Ceramic CGA6P1X7R1C226M250AC

    1

     

    See section 2.1.3 in AN99497 Designing a Power Management System with S6BP201A, S6BP202A, and S6BP203A for details on how to set the switching frequency.