Source drive chip having a power supply circuit and display apparatus

A display apparatus, comprising:

• a display panel;
• and
• a power supply circuit comprising:
• a charge pump configured to provide a negative voltage level based on an external positive voltage power supply and comprising:
• a first switch;
• a second switch;
• a third switch;
• a fourth switch;
• a first on-chip capacitor comprising:
• a first end configured to couple through the first switch to the external positive voltage power supply;
• and
• a second end coupled by the third switch to a ground;
• and
• a second on-chip capacitor comprising:
• a third end coupled in series to the second switch and to the ground;
• and
• a fourth end coupled in series with the fourth switch and configured to provide the negative voltage level to the reference source generation circuit;
• a reference source generation circuit coupled with the charge pump and configured to provide a reference voltage based on the negative voltage level;
• and
• a low-dropout (LDO) regulator coupled to the load circuit and to the reference source generation circuit and configured to output a power supply voltage to the load circuit based on the reference voltage and an external negative voltage power supply.