Hi I've been building a power supply. Step down 120 60hz to 28v. Put threw bridge rectifier. Then put threw regulator. 2 1k uf capacitorsand a .1 cap are in parrallel with the input of the regulator lm317. Then 100 ohms resistor from. The output connects with a potentiometer of 5000 ohms which connects to adjust of regulator and ground. Then on the output there's a1ohm capacitor in parrallel.
The problem is I'm trying to hit 19 volts but everytime I raise itusing potentiometer it hits 14 volts then jumps to 5volts.
I think its most likely because I don't have a heat sink (radioshack didn't have ithad to buy from jamco). But I thought that it gets hotter when the difference from input voltage to output was higher, so it. Seemed strange to me that it would jump from the. High output to. Low output voltage.
Any ideas as to problem ? Also I want 1.5 amps and I hink lm317 is for less anyone know a better regulator to order ?
The problem is I'm trying to hit 19 volts but everytime I raise itusing potentiometer it hits 14 volts then jumps to 5volts.
I think its most likely because I don't have a heat sink (radioshack didn't have ithad to buy from jamco). But I thought that it gets hotter when the difference from input voltage to output was higher, so it. Seemed strange to me that it would jump from the. High output to. Low output voltage.
Any ideas as to problem ? Also I want 1.5 amps and I hink lm317 is for less anyone know a better regulator to order ?