Voltage  reference  and  bandgap  circuits  

Basic  blocks  for  voltage  reference  circuits  

Characteris8cs  of  bipolar  transistors  

Temperature  dependence  of  BJT  characteris8cs  

Temperature  dependence  of  ΔVBE  

Temperature-­‐compensa8on  of  VBE  voltage  

Temperature-­‐constant  Reference  Voltage:  “Bandgap-­‐Reference”  

Opera8on  of  Bandgap-­‐Reference  Circuit  

Bandgap-­‐Reference  Circuit  

Gummel  plot  of  BJT  

Startup-­‐Problem  of  Bandgap-­‐Reference  Circuit  

Adjustment  of  bandgap  reference  voltage  

Undervoltage  detec8on  circuit  based  on  the  bandgap  reference  principle  

Undervoltage  detec8on  circuit  

CMOS  Compa8ble  Bandgap  Reference  

Bandgap  reference  with  all  npn-­‐collectors  connected  to  VDD  

Bandgap  reference  in  a  n-­‐well  CMOS  technology  

„Widlar“  Bandgap  –  Reference  

Current  -­‐  Reference  based  on  ΔVBE  

Cross-­‐coupled  current  source  based  on  ΔVBE  

Adjustable  Z-­‐diode  

Z-­‐diode  voltage  mul8plier