Datasheet

Figure 165. Typical
Current vs Voltage
curves of a GPIO
output.
Figure 165 shows the effect on the output voltage as the current load on the pin increases. You can clearly see the effect
of the different drive strengths; the higher the drive strength, the closer the output voltage is to IOVDD (or 0V) for a given
current. The minimum V
OH
and maximum V
OL
limits are shown in red. You can see that at the specified current for each
drive strength, the voltage is well within the allowed limits, meaning that this particular device could drive a lot more
current and still be within V
OH
/V
OL
specification. This is a typical part at room temperature, there will be a spread of other
devices which will have voltages much closer to this limit. Of course, if your application doesn’t need such tightly
controlled voltages, then you can source or sink more current from the GPIO than the selected drive strength setting, but
experimentation will be required to determine if it indeed safe to do so in your application, as it will be outside the scope of
this specification.
5.3. Power Supplies
Table 652. Power
Supply Specifications
Power Supply Supplies Min Typ Max Units
IOVDD
a
Digital IO 1.62 1.8 / 3.3 3.63 V
DVDD Digital core 0.99 1.1 1.21 V
VREG_IOVDD Voltage regulator 1.62 1.8 / 3.3 3.63 V
USB_IOVDD USB PHY 3.135 3.3 3.63 V
ADC_IOVDD
b
ADC 1.62 3.3 3.63 V
a
If IOVDD <2.5V, GPIO VOLTAGE_SELECT registers should be adjusted accordingly. See Power Supplies for details.
b
ADC performance will be compromised at voltages below 2.97V
RP2040 Datasheet
5.3. Power Supplies 636