74VHC244 OCTAL BUS BUFFER WITH 3 STATE OUTPUTS (NON INVERTED) ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ HIGH SPEED: tPD = 3.9 ns (TYP.) at VCC = 5V LOW POWER DISSIPATION: ICC = 4 µA (MAX.) at TA = 25 oC HIGH NOISE IMMUNITY: VNIH = VNIL = 28% VCC (MIN.) POWER DOWN PROTECTION ON INPUTS SYMMETRICAL OUTPUT IMPEDANCE: |IOH| = IOL = 8 mA (MIN) BALANCED PROPAGATION DELAYS: tPLH ≅ tPHL OPERATING VOLTAGE RANGE: VCC (OPR) = 2V to 5.5V PIN AND FUNCTION COMPATIBLE WITH 74 SERIES 244 IMPROVED LATCH-UP IMMUNITY LOW NOISE VOLP = 0.9V (Max.) DESCRIPTION The 74VHC244 is an advanced high speed CMOS OCTAL BUS BUFFER (3-STATE) fabricated with sub-micron silicon gate and double-layer metal wiring C2MOS technology. G output enable governs four BUS BUFFERs. M (Micro Package) T (TSSOP Package) ORDER CODES : 74VHC244M 74VHC244T This device is designed to be used with 3 state memory address drivers, etc. Power down protection is provided on all inputs and 0 to 7V can be accepted on inputs with no regard to the supply voltage. This device can be used to interface 5V to 3V. All inputs and outputs are equipped with protection circuits against static discharge, giving them 2KV ESD immunity and transient excess voltage. PIN CONNECTION AND IEC LOGIC SYMBOLS June 1999 1/8 74VHC244 INPUT EQUIVALENT CIRCUIT PIN DESCRIPTION PIN No SYMBOL 1 1G NAME AND FUNCT ION 2, 4,6, 8 1A1 to 1A4 Data Inputs 9, 7,5, 3 2Y1 to 2Y4 Data Outputs 11, 13, 15, 17 2A1 to 2A4 Data Inputs 18, 16, 14, 12 1Y1 to 1Y4 Data Outputs Output Enable Input 19 2G 10 GND Ground (0V) Output Enable Input 20 VCC Positive Supply Voltage TRUTH TABLE INPUT G OUTPUT An Yn L L L L H H H X Z X:”H” or ”L” Z: High impedance ABSOLUTE MAXIMUM RATINGS Symbol VCC Parameter Supply Voltage VI DC Input Voltage VO DC Output Voltage Value Unit -0.5 to +7.0 V -0.5 to +7.0 V -0.5 to VCC + 0.5 V IIK DC Input Diode Current - 20 mA IOK DC Output Diode Current ± 20 mA IO DC Output Current ± 25 mA DC VCC or Ground Current ± 75 mA ICC orIGND Tstg TL Storage Temperature Lead Temperature (10 sec) -65 to +150 o 300 o C C Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. RECOMMENDED OPERATING CONDITIONS Symbol VCC Parameter Supply Voltage Unit V VI Input Voltage 0 to 5.5 V VO Output Voltage 0 to VCC V Top Operating Temperature dt/dv Input Rise and Fall Time (see note 1) (VCC = 3.3 ± 0.3V) (V CC = 5.0 ± 0.5V) 1) VIN from 30% to70%of VCC 2/8 Valu e 2.0 to 5.5 -40 to +85 0 to 100 0 to 20 o C ns/V ns/V 74VHC244 DC SPECIFICATIONS Symb ol VIH VIL VOH VOL IOZ II ICC Parameter T est Cond ition s Value T A = 25 o C V CC (V) Min. Typ . Un it -40 to 85 o C Max. Min . Max. High Level Input Voltage 2.0 1.5 1.5 3.0 to 5.5 0.7VCC 0.7VCC Low Level Input Voltage 2.0 0.5 0.5 3.0 to 5.5 0.3VCC 0.3VCC High Level Output Voltage Low Level Output Voltage High Impedance Output Leakage Current Input Leakage Current Quiescent Supply Current 2.0 IO=-50 µA 1.9 2.0 1.9 3.0 IO=-50 µA 2.9 3.0 2.9 4.5 IO=-50 µA 4.4 4.5 4.4 3.0 IO=-4 mA 2.58 2.48 4.5 IO=-8 mA 3.94 3.8 V V V 2.0 IO=50 µA 0.0 0.1 0.1 3.0 IO=50 µA 0.0 0.1 0.1 4.5 IO=50 µA 0.0 0.1 0.1 V 3.0 IO=4 mA 0.36 0.44 4.5 IO=8 mA 0.36 0.44 ±0.25 ±2.5 µA 5.5 VI = VIH orVIL VO = VCC orGND 0 to 5.5 VI = 5.5V or GND ±0.1 ±1.0 µA 5.5 VI = VCC orGND 4 40 µA AC ELECTRICAL CHARACTERISTICS (Input t r = tf =3 ns) Symb ol Parameter V CC (V) Test Co ndition CL (pF ) Value o T A = 25 C Min. Typ . Max. 5.8 8.4 8.3 11.9 3.9 5.5 5.4 7.5 Un it o -40 to 85 C Min . Max. 1.0 10.0 1.0 13.5 1.0 6.5 1.0 8.5 tPLH tPHL Propagation Delay Time 3.3(*) 3.3(*) 5.0(**) 5.0(**) 15 50 15 50 tPZL tPZH Output Enable Time 3.3 3.3(*) (*) 15 50 RL = 1KΩ RL = 1KΩ 6.6 9.1 10.6 14.1 1.0 1.0 12.5 16.0 5.0(**) 5.0(**) 3.3(*) 5.0(**) 3.3(*) 5.0(**) 15 50 50 50 50 RL = 1KΩ RL = 1KΩ RL = 1KΩ RL = 1KΩ 4.7 6.2 10.3 6.7 7.3 9.3 14.0 9.2 1.5 1.0 1.0 1.0 1.0 1.0 8.5 10.5 16.0 10.5 1.5 1.0 tPLZ tPHZ Output Disable Time tOSLH tOSHL Output to Output Skew Time (note 1) 50 ns ns ns ns (*) Voltage range is 3.3V ± 0.3V (**) Voltage range is 5V ± 0.5V Note 1: Parameter guaranteed by design. tsoLH = |tpLHm- tpLHn|, tsoHL = |tpHLm - tpHLn| 3/8 74VHC244 CAPACITIVE CHARACTERISTICS Symb ol Parameter T est Cond ition s Value T A = 25 o C Min. Un it -40 to 85 o C Typ . Max. Input Capacitance 4 10 COUT Output Capacitance 6 pF CPD Power Dissipation Capacitance (note 1) 19 pF CIN Min . Max. 10 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) DYNAMIC SWITCHING CHARACTERISTICS Symb ol Parameter T est Cond ition s Dynamic Low Voltage Quiet Output (note 1, 2) 5.0 VIHD Dynamic High Voltage Input (note 1, 3) 5.0 VILD Dynamic Low Voltage Input (note 1, 3) 5.0 VOLP VOLV Value T A = 25 o C V CC (V) Min. -0.9 CL = 50 pF Un it -40 to 85 o C Typ . Max. 0.6 0.9 Min . Max. -0.6 3.5 V 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. TEST CIRCUIT T EST tPLH , tPHL SW IT CH Open tPZL , tPLZ VCC tPZH , tPHZ GND CL = 15/50 pF or equivalent (includes jig and probe capacitance) RL = R1 = 1KΩ orequivalent RT = ZOUT of pulse generator (typically 50Ω) 4/8 74VHC244 WAVEFORM 1: PROPAGATION DELAYS (f=1MHz; 50% duty cycle) WAVEFORM 2: OUTPUT ENABLE AND DISABLE TIME (f=1MHz; 50% duty cycle) 5/8 74VHC244 SO-20 MECHANICAL DATA mm DIM. MIN. TYP. A a1 inch MAX. MIN. TYP. 2.65 0.10 0.104 0.20 a2 MAX. 0.004 0.007 2.45 0.096 b 0.35 0.49 0.013 0.019 b1 0.23 0.32 0.009 0.012 C 0.50 0.020 c1 45 (typ.) D 12.60 13.00 0.496 0.512 E 10.00 10.65 0.393 0.419 e 1.27 0.050 e3 11.43 0.450 F 7.40 7.60 0.291 0.299 L 0.50 1.27 0.19 0.050 M S 0.75 0.029 8 (max.) P013L 6/8 74VHC244 TSSOP20 MECHANICAL DATA mm DIM. MIN. inch TYP. MAX. A MIN. TYP. MAX. 1.1 0.433 A1 0.05 0.10 0.15 0.002 0.004 0.006 A2 0.85 0.9 0.95 0.335 0.354 0.374 b 0.19 0.30 0.0075 0.0118 c 0.09 0.2 0.0035 0.0079 D 6.4 6.5 6.6 0.252 0.256 0.260 E 6.25 6.4 6.5 0.246 0.252 0.256 E1 4.3 4.4 4.48 0.169 0.173 0.176 e 0.65 BSC 0.0256 BSC K 0o 4o 8o 0o 4o 8o L 0.50 0.60 0.70 0.020 0.024 0.028 A A2 A1 b K e L E c D E1 PIN 1 IDENTIFICATION 1 7/8 74VHC244 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. 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