Electric circuit and electronic apparatus

An electric circuit comprising:

• a first power-supply line;
• a second power-supply line;
• a ground line;
• a first circuit including a first circuit element configured to transmit a first digital signal, the first circuit being configured to be electrically connected to the first power-supply line via a first power-supply terminal and electrically connected to the ground line via a first ground terminal;
• a second circuit including a second circuit element configured to transmit a second digital signal whose transmission rate is lower than a transmission rate of the first digital signal, the second circuit being configured to be electrically connected to the second power-supply line via a second power-supply terminal and electrically connected to the ground line via a second ground terminal;
• an RC series circuit disposed between the first power-supply terminal and the first ground terminal;
• a capacitor disposed between the second power-supply terminal and the second ground terminal;
• and
• a noise filter disposed between the first power-supply line and the second power-supply line.