TEST CIRCUITS (Continued)

External Com p onents

Tr : XP161A1355PR (N-ch Power MOSFET, TOREX) As the breakdown voltage of XP161A1355PR is 8V, take care with the power supply voltage. With output voltages over 6V, use the XP161A1265PR with a breakdown voltage of 12V. V
ST1 : XP161A1355PR = 1.2V (MAX.) XP161A1265PR = 1.5V (MAX.) L : 22 H (CR54, SUMIDA FOSC=300kHz) 47 H (CR75, SUMIDA FOSC=100, 180kHz) 10 H (CR54, SUMIDA FOSC=500kHz) SD : MA2Q735 (Schottky diode, MATSUSHITA) C
IN : 16V, 220 F (Aluminium Electrolytic Capacitor) CL : 16V, 47 F + 47 F (Tantalum capacitor, NICHICON MCE) NPN Tr type: Tr : 2SD1628 (SANYO) Rb : 500 (Adjust according to load and Tr. hFE levels) Cb : 2200pF (Ceramic Type) Set up so that CB < 1 (2 x RB x FOSC x 0.7) C, D, F type (soft-start externally set-up): C
SS : 0.1 F (Ceramic capacitor) R
SS : 470k (C, F Type), 220k (D Type) B, D type (FB versions) R
FB : Set up so that R
FB1 R
FB2 = V
OUT - 1 (V
OUT = setting output voltage), Please use with R
FB1 + R
FB2 2M C
FB : Set up so that fzfb = 1 (2 x x CFB x RFB1) is within the 0.1 to 20kHz range (10kHz conventional) Adjustments necessary in respect of L, C
L . e.g V
OUT = 3.0V R
FB1 = 400k , R
FB2 = 200k , C
FB = 47pF For using MOSFET, We recommend using TOREX MOSFETs, which has a gate protection diode built-in. GATE PROTECTION DIODE BUILT-IN MOSFET R
ds (ON) XP161A1355PR 0.15 @ Vgs=1.5V XP161A1265PR 0.095 @ Vgs=2.5V

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