Boost DC-DC help

[crutschow]

i input my requirements for Vf for diode to be 0.95V and transistor voltage drop be 2.6V (using power mos BUZ11) and got the following results. the Inductor Current Ripple and Output Voltage Ripple were set to 5%.

Volts In 18 V
Volts Out 50 V
Load Current 1 A
Freq. 300 KHz
Vripple 2.5 V
Duty Cycle 68.148914167528 %
Ipp Inductor 2 A
Ipk Inductor 2 A
Irms 0.577 A
L 17.49 uH
C 0.908 uF

4. Btw, Are there any parameters I need to calculate? before i get my components?

Your component values look okay for that frequency.

You might want to drop the operating frequency. (The reference circuit you mentioned uses 44kHz). Operating at 300kHz will increase your switching losses.

You may want to increase your capacitor size to reduce the ripple, although it's probably not a problem since it's going to a battery.

Is that diode drop from one or two diodes? Are you using schottky diodes to minimize the diode power loss?

The 2.6V drop for the transistor is much too high. The BUZ11 has a maximum on resistance of 0.04 ohms with 10V Vgs, so it's drop should be much lower than that.