Car Laptop Power Supply Adaptor


The laptop adaptor described here plugs into a car cigarette lighter socket and produces a 19V nominal output voltage adjustable by + - 0.5V. 

The input voltage range is from 9.2V to 15V and the output voltage shows good regulation even with large fluctuations of the input voltage. The output can supply 5A continuosly with brief excursions up to 10A. 

The laptop power supply described here plugs into a car cigarette lighter socket and produces a 19V nominal output voltage adjustable by + - 0.5V. The input voltage range is from 9.2V to 15V and the output voltage shows good regulation even with large fluctuations of the input voltage. 

The output can supply 5A continuosly with brief excursions up to 10A. The power semiconductor heatsinks of this laptop power supply are dimensioned fo 5A continuous so extended operation up to 10A will increase dissipation in the adapter and in extreme cases will cause the input fuse to complain.


Laptop PSU Adaptor Parts List 


Resistors: R1 = 5k6 
R2 = 51k (51k1) 
R3 = 9k1 (9k1) 
R4 = 1M 
R5 = 4k7 
R6,R8 = 15k 
R7 = 27k 
R9,
R10 = 6,8 
R11 = 10k 
R12 = 100 
P1 = 5k preset 

Capacitors: 

C1-C4 = 3300µF 16V, radial, low ESR, diam. 12.5 mm, e.g. Panasonic EEUFC1C332 (Farnell) 
C5,C10 = 1µF MKT, lead pitch 5mm or 7.5mm (larger version preferred) 
C12 = 1µF MKT, lead pitch 5 mm 
C6-C9 = 2200µF 25V radial, low ESR, diam. 12.5mm, e.g., EEUFC1E222 (Farnell) 
C11 = 22nF, lead pitch 5mm 
C13 = 2nF2, lead pitch 5mm 
C14,C15 = 100nF ceramic, lead pitch 5mm 
C16 = 10µF 63V radial 

Inductors: 

L1 = 56µH, 21 turns 10 x 0.5 mm ECW, parallel 
1 x ETD 29 coil forner, vertical mounting, Epcos B66359X1014T1 (Schuricht # 331622) 2 x ETD 29 clamp, Epcos B66359-A2000 (Schuricht # 333862) 
2 x ETD 29 core half, material # N67, air gap 0.5mm, Epcos B66358-G500-X167 (Schuricht # 333840) 

Semiconductors: 

D1 = MBR1645 (International Rectifier) (e.g. Reichelt, Segor) 
T1 = IRL2505 (International Rectifier) TO-220AB case, (e.g., RS Components)  
T2 = BD139 
T3 = BD140 IC1 = UC3843N (Texas Instruments) (e.g. Reichelt, Segor) 

Miscellaneous: 

K1-K4 = 2-way spade terminal, vertical, PCB mount 
F1 = fuse, 10A/T (slow) 6.3 x 32 mm (¼ x 1¼ inch) + 2 fuse holders for 6.3 mm diameter and PCB mounting 
2 x heatsink type SK104-STC (or STS) TO220 38.1mm, 11K/W (Fischer Electronic) 
Isolating washers for T1 and D1 (TO-220AB) + isolating bushes PCB 

Source : Magazine Elektor January 2006

Test Run your circuit

3 Comments

Please Select Embedded Mode To Show The Comment System.*

Previous Post Next Post