IOZ Off-State (High-Impedance State) Output Current (of a 3-State Output)
JEDEC – no definition offered
TI – The current flowing into an output with the input conditions applied that, according to the product specification, establishes the high-impedance state at the output
TI data sheets specify currents flowing out of a device as a negative value. The electrical characteristic, IOZ, is verified utilizing the IOZH and IOZL tests. Two tests are required to verify the integrity of both the p- and n-channel transistors.
For bidirectional I/O that have bus hold on the data input/output pins, there should not be an IOZ specification because the bus-hold output supplies enough current to overcome any internal output leakage.
An exception to this is an IOZH specification for an overvoltage-tolerant bus-hold output with a test condition of VO >> VCC. This is used to indicate that the overvoltage-tolerant bus-hold output has a Schottky blocking diode in series with the output p-channel pullup transistor to VCC and Ioff circuitry, preventing the upper p-channel from turning on, which prevents current from flowing from the output back into the VCC supply. See II(hold) and Ioff for more information.