12 volts to 8.5 volts
The TINY new PlayStation "Slim Line PSTwo" is small. And it is a perfect companion for your mobile entertainment system. Hook it up to your indash flip out LCD screen and play racing games all day long while in your car.
Skip class and go play a game with your buddies in the parking lot. Stuck in L.A. traffic? Play Grand Theft Auto: San Andreas.
The PSTwo uses 8.5 volts direct current (DC) and about 5.3 amps. Your car battery is around 12 volts DC.
You can't just take a resistor to drop the voltage down. The car's voltage is constantly fluctuating. While the engine is off, the voltage may be 12 volts, but as soon as it revs, the voltage could be 14 volts.
That precious PSTwo needs a pretty constant 8.5 volts to function.
Old School — Inefficient
You could spend fourty or fifty bucks on a 160 watt power inverter. Plug it into your car's 12 volt DC cigarette lighter, and it gives you a 110 volt AC power outlet. Plug in the power adapter from Sony, and bring that 110 volt alternating current (AC) down to 8.5 volt DC. Waste a lot of power, find a place to put a bulky inverter and adapter, and drain your battery quickly.
The Solution — Smaller than a Peach
Take that 12 directly to 8.5 with minimal energy (heat) loss. Do it in a very tiny package, and for not much money.
You need a variable voltage regulator, a heat sink, heat sink compound, 2 resistors, and an optional mounting/insulating kit.
Wiring Diagram
Parts List
- TO3 Heatsink - Mouser 567-680-125A
- LM138K TO3 Regulator - Mouser 511-LM138K
- R1 240 Ohm 1/4W - Mouser 71-CCF07-G-240/R
- R2 1.4 Kohm 1/4W - Mouser 71-RN60C-F-1.4K
- Insulating/Mounting Kit - Mouser 71-RN60C-F-1.4K
- Silicone-Base Heat Sink Compound - Mouser 526-NTE303