9.2.2 Detailed Design Procedure

1. Recommended Input Conditions
   • For specified high and low levels, see V_IH and V_IL in the Electrical Characteristics table.
   • Inputs are overvoltage tolerant allowing them to go as high as V_I(max) in the Absolute Maximum Ratings table at any valid V_CC.
2. Recommended Output Conditions
   • Output voltage must not exceed V_O(max) as specified in the Absolute Maximum Ratings table.
   • Pull-up resistor (R) selection depends on three primary factors: desired output high voltage (V_OH), which is directly related to total leakage current into the SN74AUP1G240 and the peripheral device's input (I_L), desired 0 to 90% rising edge time (t_r), which is directly related to the parasitic line capacitance (C_P), and the maximum current during low output (I_OL), which is directly related to the supply value. These three equations govern pull-up resistor selection:
     • R ≤ ( V_CC – V_OH ) / I_L
     • R ≤ t_r / ( 2.3 * C_P)
     • R ≥ V_CC / I_OL(max)