Share high voltage ultra low noise LDO test results

LDO The design requirements ：

Output 150V, load 0~500mA, The peak value of waveform is better than 2mVrms;

The following is the effective value measured by the audio analyzer RMS And peak to peak P-P. Test bandwidth 10Hz~1Mhz.

chart 1 Load current 500mA Effective value of waveform at rms

chart 2 load 500mA Peak to peak value of waveform p-p

chart 3 load 100mA At the time of the rms
​​​​

chart 4 load 100mA Peak to peak at p-p

          When empty , Output 150.42V, With load 500mA Time output 150.15V, It's lower than when it's empty 0.27V, Proportion 0.18%, Load stability 99.82%（1-0.18%）, The stability is ok . Output impedance ：0.27V / 500mA = 0.54Ω, Specific low pressure LDO Of IC High output impedance , But the high voltage built as a discrete device LDO, This output impedance is acceptable to me .

          In the whole load range (0-500mA） The peak and peak of output noise can be controlled within 500uVrms within , Meet the design requirements .

At output load 500mA when , There will be 2W The heat of , So we need to 2W Heat sink .

chart 5 A physical picture , For load rigol Load tester
​​​​