diode such as the 1N5819. Motorola makes the
MBR0530 for surface mount. For lower output power a
1N4148 can be used although efficiency and start-up
voltage will suffer substantially.
COMPONENT POWER DISSIPATION
Operating in discontinuous mode, the power loss in
the winding resistance of the inductor is approximately
equal to
PDL
=
2 * TON * (RS) * VOUT + VD * (POUT )
3 L
VOUT
SS6639
where POUT=VOUT * IOUT ; RS=Inductor DC R;
VD = Diode drop.
The power dissipated in switching losses is
PDsw = 2 * TON * (RON ) * ( ) IOUT * (POUT )
3 L
The power dissipated in the rectifier diode is
PDD = VD * (POUT )
VOUT
Rev.2.01 6/26/2003
www.SiliconStandard.com
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