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| 74VHC244 |
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 STMICROELECTRONICS
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4 page 
CAPACITIVE CHARACTERISTICS Symb ol Parameter T est Cond ition s Val ue Un it TA =25 oC -40 to 85 oC Min. Typ . Max. Min . Max. CIN Input Capacitance 4 10 10 pF COUT Output Capacitance 6 pF CPD Power Dissipation Capacitance (note 1) 19 pF 1) CPD isdefined as the value of the IC’sinternal equivalent capacitance which is calculated fromthe operating current consumption without load. (Referto Test Circuit).Average operating current can be obtained by the following equation. ICC(opr) = CPD • VCC • fIN +ICC/48(per Gate) TEST CIRCUIT T EST SW IT CH tPLH,tPHL Open tPZL,tPLZ VCC tPZH,tPHZ GND CL = 15/50 pF or equivalent (includes jig and probe capacitance) RL =R1 =1K Ω orequivalent RT =ZOUT of pulse generator (typically 50 Ω) DYNAMIC SWITCHING CHARACTERISTICS Symb ol Parameter T est Cond ition s Val ue Un it VCC (V) TA =25 oC -40 to 85 oC Min. Typ . Max. Min . Max. VOLP Dynamic Low Voltage Quiet Output (note 1, 2) 5.0 CL =50pF 0.6 0.9 V VOLV -0.9 -0.6 VIHD Dynamic High Voltage Input (note 1, 3) 5.0 3.5 VILD Dynamic Low Voltage Input (note 1, 3) 5.0 1.5 1) Worst case package. 2) Max number of outputs defined as (n). Data inputs are driven 0V to 5.0V, (n -1) outputs switching and one output at GND. 3) Max number of data inputs (n) switching. (n-1) switching 0V to5.0V. Inputs under test switching: 5.0V to threshold (VILD), 0V to threshold (VIHD), f=1MHz. 74VHC244 4/8 |
