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MITSUBISHI MICROCOMPUTERSMSM82C43PINPUT/OUTPUT EXPANDERExample:To use the 20mAsinking capability at port7, find the effectson the sinking capabilities of the other I/O lines. Assumethe M5M82C43P is driving loads as shown below:3 lines: 20mA (VOL = 1.OV max, port 7 only)4 lines: 4mA (VOL = 0.45V max)9 lines: 1.6mA (VOL = 0.45V max)Is this within the allowable limit?I IOL = (20mA X 3) + (4mA X 4) + (1.6mA X 9) =90.4mAFrom the curve it is seen that with respect to IOL = 4mA, IOLis 93mA (point B) and that the above load of 90.4mA is withinthe limit of 93mA.Note: The sinking current of port 4 -- 7 must not exceed30mA regardless of the value of VOL.M5M80C49-XXXPFig.2PROGir-----------~------------~------------~----------~Expansion Interface exampleII• MITSUBISHI..... ELECTRIC6-37