simple front end design from 1v to 400v peak to peak

[santlaha]

front end simplified.
** input impedance increased to >1Meg
** accidental over voltage protection upto 600V
**single point voltage selection
** linearity adjustment
mode 0 ==>3v peak to peak(-1.5v to +1.5v)
mode 1 ==>12v peak to peak(-6v to +6v)
mode 2 ==>100v peak to peak(-50v to +50v)
mode 3 ==>400v peak to peak (-200 to +200V)

mode 1

sim_12vmax.zip

mode 3
tinadiag 400v.zip

[gilesp1729]

Hi,
Could you publish a web-readable schematic?