Is it a fixed 5V (LT1175-5) or an adjustable (LT1175)?
If it is a fixed one, the resistors set output voltage to -20V which cannot work. If it is an adjustable, output voltage is set to -15V.
Which output voltage do you expect ?
According to datasheet :
You have to install an output capacitor; ie. a 10uF ecap and also an input one not less then 33uF ecap, good quality one.
Shtdn should left open, this will enable the regulator.
If it is a fixed one, the resistors set output voltage to -20V which cannot work. If it is an adjustable, output voltage is set to -15V.
Which output voltage do you expect ?
According to datasheet :
You have to install an output capacitor; ie. a 10uF ecap and also an input one not less then 33uF ecap, good quality one.
Shtdn should left open, this will enable the regulator.
adjustable lt1175, I would like to get -15v on the output, I tried to leave the SHDN open but nothing comes out of the regulator, maybe I didn't understand something that's why I ask for help
Thanks all, problem solved. in reality even if with the multimeter I measured 18.5v on the Vin in reality it had a ripple that brought it above the near 20v by turning off the regulator