jano2358
Newbie level 4
hi!
I making a dual power supply (+-12V) with a pair of DC-DC converters taking feed from 18V brick.
The positive side regulates with a L7987 to 13V and a LDL212 to 12V, I added a bit more of protection with a resistor (1ohm on the test, planed 0.3 later) in series with the LDO, differentiator and comparator, if the compared value rises over the reference the EN pin of LDL212 is shorted.
This works well with overcurrent and short circuit to against GND, but if i short the output against the negative rail, the LDL212 is destroyed even if the EN pin is lowered by the protection.
The datasheet says this device output should not be less than -0.3V and I guess this is the problem, but how I can protect the device from this condition? or is better option to choose other LDO? if yes: any recommendation (less than 0.6V and 1.5A). Thanks!
I making a dual power supply (+-12V) with a pair of DC-DC converters taking feed from 18V brick.
The positive side regulates with a L7987 to 13V and a LDL212 to 12V, I added a bit more of protection with a resistor (1ohm on the test, planed 0.3 later) in series with the LDO, differentiator and comparator, if the compared value rises over the reference the EN pin of LDL212 is shorted.
This works well with overcurrent and short circuit to against GND, but if i short the output against the negative rail, the LDL212 is destroyed even if the EN pin is lowered by the protection.
The datasheet says this device output should not be less than -0.3V and I guess this is the problem, but how I can protect the device from this condition? or is better option to choose other LDO? if yes: any recommendation (less than 0.6V and 1.5A). Thanks!