12-to-24 V Converter

This DC-to-DC converter delivers a maximum power of about 36 watts at an efficiency of 90%. Apart from a modern FET and a Schottky diode, this circuit is comprised entirely of familiar and inexpensive parts. In spite of this, the specifications are excellent:– Efficiency: approx 90%– Ripple voltage: max. 10 mV– Output current: max. 1.5 A– Switching frequency: 40 kHz– Input voltage: 12 V– Output voltage: 24 V regulatedThe switching element is a fast power FET (T8). This FET has a relatively high input capacitance and is switched on and off by a push/pull stage consisting of two RF transistors (T5/T6). Schottky-diode D2 increases turn-off speed even further, which is crucial here because we are aiming to obtain the highest possible efficiency.

Continue reading this Elektor article?

Try a digital membership (Green) for 6 months for only €5.33 per month.

Unlimited access to online Member Only articles
3 new editions Elektor Magazine (digital)
More than 5000 Gerber files
20% member discount on e-books (at elektor.com)
10% member discount on Products (at elektor.com)

Try for 6 months.
Stops Automatically.

What is Elektor Exclusive?

Materials

014025-PCB.pdf

Component list

Resistors:
R1,R2 = 68kOhm
R3,R4 = 1kOhm 2
R5 = 2kOhm 2
R6 = 3kOhm 3
R7 = 15kOhm
R8 = 1kOhm
R9 = 4Ohm k7
R10 = 6kOhm 8
Capacitors:
C1 = 470pF
C2 = 270pF
C3 = 33pF
C4 = 100nF
C5 = 1000µF 16V radial
C6,C7 = 470µF 35V radial
Inductors:
L1 = 25 turns 0.5 dia. ECW, 10 mm dia., no core