I'm building a symmetrical buffer supply.
crc-lm317/337 to +/- 13.1V then crc then two of those miniature boards from ebay: TPS7A3301 -5V -9 -12 -15V -18V 1A Ultra Low Noise LDO Negative Voltage Regulator
Then a little more CRC and then the buffer preamp.
Plus side works normaly, but negative ldo regulator slowly jumps to Vin and after I set it to -12v it stars slowly dropping to minimum around -1 v
Input voltage check, shorts and bad wires after regulator checked, checked if EN boltage is too high cause datasheet says 10V max but its dropping on smaller voltages too. Tried a second board and its the same.
Thanks!
Tried with a 250k load resistor too
crc-lm317/337 to +/- 13.1V then crc then two of those miniature boards from ebay: TPS7A3301 -5V -9 -12 -15V -18V 1A Ultra Low Noise LDO Negative Voltage Regulator
Then a little more CRC and then the buffer preamp.
Plus side works normaly, but negative ldo regulator slowly jumps to Vin and after I set it to -12v it stars slowly dropping to minimum around -1 v
Input voltage check, shorts and bad wires after regulator checked, checked if EN boltage is too high cause datasheet says 10V max but its dropping on smaller voltages too. Tried a second board and its the same.
Thanks!
Tried with a 250k load resistor too
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Well, the board has a few smd bugs on it so I presumed some would be stability caps mentioned in datasheet. Wrong. Problem solved with a few ceramics and lytics directly to pins.
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