Hallo

40mA pro Pin würde ich auch sagen. Außerdem darf der Gesamtstrom mehrerer Ports je nach Gehäuseform und verwedeten Ports bestimmte Summenwerte nicht überschreiten. Z.B. beim ATMega32:

DC Current per I/O Pin ............................................... 40.0 mA
DC Current VCC and GND Pins......................... 200.0 mA and
400.0 mA TQFP/MLF
3. Although each I/O port can sink more than the test conditions (20 mA at Vcc = 5V, 10 mA at Vcc = 3V) under steady state
conditions (non-transient), the following must be observed:
PDIP Package:
1] The sum of all IOL, for all ports, should not exceed 200 mA.
2] The sum of all IOL, for port A0 - A7, should not exceed 100 mA.
3] The sum of all IOL, for ports B0 - B7,C0 - C7, D0 - D7 and XTAL2, should not exceed 100 mA.
TQFP and QFN/MLF Package:
1] The sum of all IOL, for all ports, should not exceed 400 mA.
2] The sum of all IOL, for ports A0 - A7, should not exceed 100 mA.
3] The sum of all IOL, for ports B0 - B4, should not exceed 100 mA.
4] The sum of all IOL, for ports B3 - B7, XTAL2, D0 - D2, should not exceed 100 mA.
5] The sum of all IOL, for ports D3 - D7, should not exceed 100 mA.
6] The sum of all IOL, for ports C0 - C7, should not exceed 100 mA.
If IOL exceeds the test condition, VOL may exceed the related specification. Pins are not guaranteed to sink current greater
than the listed test condition.
(Das findet man unter "Electrical Characteristics")

Gruß

mic