www.national.com

24

Revision 1.0

2.2.7

Output, Open-Drain Buffer

Output, TTL Compatible Open-Drain output buffer capable of sinking n mA. Output from these signals is open-drain and

is never forced high.

2.2.8

Output, PCI 3.3V

2.2.9

Output, Open-Drain, PCI 3.3V

2.2.10

Exceptions

3. The following pins have an internal static pull-up resistor (when enabled) and therefore may have leakage current to

GPIO00-07, GPIOE10-17, GPIO20-27, GPIO30-37, GPIOE40-47, GPO50-57 and GPIO60-63.

4. The following strap pins have an internal static pull-up resistor enabled during Power-Up reset and therefore may have

2.2.11

Terminology

Back-Drive Protection. A pin that is back-drive protected does not sink current into the supply when an input voltage higher

than the supply, but below the pin’s maximum input voltage, is applied to the pin. This is true even when the supply is inac-

tive. Note that active pull-up resistors and active output buffers are typically not back-drive protected.

5-Volt Tolerance. An input signal that is 5V tolerant can operate with input voltage of up to 5V even though the supply to

the device is only 3.3V. The actual maximum input voltage allowed to be supplied to the pin is indicated by the maximum

high voltage allowed for the input buffer. Note that some pins have multiple buffers, not all of which are 5V tolerant. In such

cases, there is a note that indicates at what conditions a 5V input may be applied to the pin; if there is no note, the low max-

imum voltage among the buffers is the maximum voltage allowed for the pin.

Symbol

Parameter

Conditions

Min

Max

Unit

Output Low Voltage

0.4

V

0.2

V

Symbol

Parameter

Conditions

Min

Max

Unit

Output High Voltage

V

Output Low Voltage

V

Symbol

Parameter

Conditions

Min

Max

Unit

Output Low Voltage

V