Hello,
This is my first message on this forum. I am making a dual power supply -12V +12V based on LM2576. The schematic is based on the constructor datasheet. Everything works fine if the current load on the +12V does not exceed 500mA (approximately). When the load current exeeds 500mA at the +12V, the supply voltage (from a bench power supply at 15V limited at 6A) starts oscilating: 1Volt amplitude at around 33Hz , the waveform is a kind of smooth sawtooth). The +12V is stable, just the supply is oscillating. It seems the -12V doe not generate this problem, it works fine at least untill 600 mA (did'nt test it on loads superior to 600mA).
Any idea about what is happening ?
Thank for your help.
This is my first message on this forum. I am making a dual power supply -12V +12V based on LM2576. The schematic is based on the constructor datasheet. Everything works fine if the current load on the +12V does not exceed 500mA (approximately). When the load current exeeds 500mA at the +12V, the supply voltage (from a bench power supply at 15V limited at 6A) starts oscilating: 1Volt amplitude at around 33Hz , the waveform is a kind of smooth sawtooth). The +12V is stable, just the supply is oscillating. It seems the -12V doe not generate this problem, it works fine at least untill 600 mA (did'nt test it on loads superior to 600mA).
Any idea about what is happening ?
Thank for your help.
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