I_BHL and I_BHH are the bus-hold low and bus-hold high sustaining currents. These currents are the guaranteed maximum currents that the input can endure without changing state. At input current which is ≤ I_BHL, the voltage level at the input pin V_I ≤ V_IL. At input current which is ≤ I_BHH, the voltage level at the input pin V_I ≥ V_IH. I_BHLO and I_BHHO are the bus-hold low and bus-hold high overdrive currents. These currents are the guaranteed minimum currents required to overdrive the inputs and force a change of logic state. At input current ≥ I_BHLO, the input state changes from a logic LOW to a logic HIGH. At input current ≥ I_BHHO, the input state changes from a logic HIGH to a logic LOW. In multipoint applications where several inputs are on the same bus-line, it is important to choose a driver that can overdrive all of the bus-hold cells. The output drive should exceed n x I_BHHO and n x I_BHLO; where n is the number of bus-hold cells on the bus-line.