Help in Bandgap waveform....

[vijay_nag]

Hello,

I a m designing Bandgap reference voltage with 1.3V supply,i getting trouble in accurate output waveform,output waveform should parabolic but i am getting different shape...i attched waveform and schematic ....please anybody can me help me....Bias current is 50ua, iam using single stage diff pair.

 

[vijay_nag]

Please any body can help me......

 

[keith1200rs]

I cannot really read the circuit, but your output voltage is low suggesting the resistor ratios are not quite right. Also, you mention a 1.3V supply but is the circuit really capable of producing a 1.22V output from a 1.3V supply? It might be worthwhile trying at a higher supply to see if that is part of the problem.

Keith.

 

[gevy]

Adjust resistor ratio for needed bandgap waveform.

 

[frankliner]

Did you intend to have m0[0:3] diode connected?