SC46208

Setting The Output Voltage

For voltage adjustable version, SC46208 adjusts the output voltage through two serial resistors, refer to fig.

below. We can calculate the output voltage through the following equation:

)X0.6V

R2

R1

(1

+

=

The selection of resistor R1, R2 should give attention to the quiescent power and external interfere. Higher

impedance reduces the quiescent current (I=0.6V/R2), and lower resistance gives better noise immunity, and is

less sensitive to interference, layout parasitics and FB node leakage current. A proper value of feed-forward

capacitor C1 can improve the noise immunity of the feedback loops, especially in an improper layout.

HANGZHOU SILAN MICROELECTRONICS CO.,LTD

REV:1.1

2008.09.10

Http://www.silan.com.cn

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