35.1.8 Pin Driver Strength Figure 35-21. ATmega48PB/88PB: I/O Pin Output Voltage vs. Sink Current (VCC = 3V) Figure 35-22. ATmega48PB/88PB: I/O Pin Output Voltage vs. Sink Current (VCC = 5V) Figure 35-23. ATmega48PB/88PB: I/O Pin Output Voltage vs. Source Current (VCC = 3V) Figure 35-24. ATmega48PB/88PB: I/O Pin Output Voltage vs. Source Current (VCC = 5V)