74VHC257 QUAD 2 CHANNEL MULTIPLEXER (3-STATE) ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ HIGH SPEED: tPD = 3.7 ns (TYP.) at VCC = 5V LOWPOWER 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 257 IMPROVED LATCH-UP IMMUNITY LOWNOISE VOLP = 0.8V (Max.) DESCRIPTION The 74VHC257 is an advanced high-speed CMOS QUAD 2 CHANNEL MULTIPLEXER (3-STATE) fabricated with sub-micron silicon gate and double-layer metal wiring C2MOS technology. It is composed of four independent 2 channel multiplexers with common SELECT and ENABLE INPUT. M (Micro Package) T (TSSOP Package) ORDER CODES : 74VHC257M 74VHC257T The 74VHC257 is a non inverting multiplexer. When the ENABLE INPUT is held ”High”, all outputs become high impedance state. If SELECT INPUT is held ”Low”, ”A” data is selected, when SELECT INPUT is ”High”, ”B” data is chosen. 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 1/9 74VHC257 INPUT EQUIVALENT CIRCUIT PIN DESCRIPTION PIN No SYMBOL NAME AND FUNCT ION 1 SELECT Common Data Select Input 2, 5, 14, 11 1A to 4A Data Input From Source A 3, 6, 13, 10 1B to 4B Data Inputs from Source B 4, 7, 12, 9 1Y to 4Y 3 State Multiplexer Outputs 15 OE 8 GND Ground (0V) 16 VCC Positive Supply Voltage 3 State Output Enable Inputs (Active LOW) TRUTH TABLE INPUT S OE SELE CT A B Y H X X X Z L L L X L L L H X H L H X L L L H X H H X = DON’T CARE Z = HIGH IMPEDANCE LOGIC DIAGRAM Thislogic diagram has notbe used to estimate propagation delays 2/9 OUTPUTS 74VHC257 ABSOLUTE MAXIMUM RATINGS Symbol VCC Parameter Value Unit -0.5 to +7.0 V -0.5 to +7.0 V -0.5 to VCC + 0.5 V Supply Voltage VI DC Input Voltage VO DC Output Voltage IIK DC Input Diode Current - 20 mA IOK DC Output Diode Current ± 20 mA IO DC Output Current ± 25 mA ± 50 mA ICC or IGND DC VCC or Ground Current Tstg Storage Temperature TL 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 VI Input Voltage VO Output Voltage Top Operating Temperature dt/dv Valu e Supply Voltage Unit 2.0 to 5.5 V 0 to 5.5 V 0 to VCC V o -40 to +85 Input Rise and Fall Time (see note 1) (VCC = 3.3 ± 0.3V) (V CC = 5.0 ± 0.5V) C 0 to 100 0 to 20 ns/V ns/V 1) VIN from 30% to70%of VCC DC SPECIFICATIONS Symb ol VIH VIL VOH VOL IOZ II ICC Parameter T est Cond ition s Value o Min. Typ . Un it o T A = 25 C V CC (V) -40 to 85 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 V I O =-50 µA IO=-50 µA 1.9 2.0 1.9 3.0 2.9 3.0 2.9 4.5 IO=-50 µA 4.4 4.5 4.4 3.0 IO=-4 mA 2.58 4.5 IO=-8 mA 3.94 2.0 I O=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 2.0 V V 2.48 3.8 V 3.0 IO=4 mA 0.36 0.44 4.5 IO=8 mA 0.36 0.44 VI = VIH or VIL VO = VCC or GND ±0.25 ±2.5 µA 5.5 0 to 5.5 VI = 5.5V or GND ±0.1 ±1.0 µA 5.5 VI = VCC or GND 4 40 µA 3/9 74VHC257 AC ELECTRICAL CHARACTERISTICS (Input t r = tf =3 ns) Symb ol Parameter 3.3(*) 15 Value T A = 25 o C Min. Typ . Max. 5.8 9.3 3.3(*) 5.0(**) 5.0(**) 3.3(*) 3.3(*) 50 15 50 15 50 8.3 3.6 5.1 7.0 9.5 12.8 5.9 7.9 11.0 14.5 1.0 1.0 1.0 1.0 1.0 14.5 7.0 9.0 13.0 16.5 5.0 5.0(**) (**) 15 50 4.0 5.5 6.8 8.8 1.0 1.0 8.0 10.0 3.3 3.3(*) 5.0(**) 5.0(**) 3.3(*) (*) 15 50 15 50 50 6.7 9.2 3.6 5.1 8.6 10.5 14.0 6.8 8.8 12.0 1.0 1.0 1.0 1.0 1.0 12.5 16.0 8.0 10.0 13.5 (**) 50 5.7 7.9 1.0 9.0 V CC (V) tPLH tPHL Propagation Delay Time A, B to Y tPLH tPHL Propagation Delay Time SELECT to Y tPZL tPZH Output Enable Time tPLZ tPHZ Output Disable Time 5.0 Test Co ndition CL (pF ) Un it -40 to 85 o C Min . Max. 1.0 11.0 ns ns ns ns (*) Voltage range is 3.3V ± 0.3V (**) Voltage range is 5V ± 0.5V 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. 10 Min . Max. Input Capacitance 4 COUT Output Capacitance 6 pF CPD Power Dissipation Capacitance (note 1) 23 pF C IN 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/4 (per Channel) 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. -0.8 C L = 50 pF Un it -40 to 85 o C Typ . Max. 0.3 0.8 Min . Max. -0.3 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. 4/9 74VHC257 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) WAVEFORM 1: PROPAGATION DELAYS FOR INVERTING CONDITIONS (f=1MHz; 50% duty cycle) 5/9 74VHC257 WAVEFORM 2: PROPAGATION DELAYS FOR NON-INVERTING CONDITIONS (f=1MHz; 50% duty cycle) WAVEFORM 3: OUTPUT ENABLE AND DISABLE TIME (f=1MHz; 50% duty cycle) 6/9 74VHC257 SO-16 MECHANICAL DATA mm DIM. MIN. TYP. A a1 inch MAX. MIN. TYP. 1.75 0.1 0.068 0.2 a2 MAX. 0.004 0.007 1.65 0.064 b 0.35 0.46 0.013 0.018 b1 0.19 0.25 0.007 0.010 C 0.5 0.019 c1 45 (typ.) D 9.8 10 0.385 0.393 E 5.8 6.2 0.228 0.244 e 1.27 e3 0.050 8.89 0.350 F 3.8 4.0 0.149 0.157 G 4.6 5.3 0.181 0.208 L 0.5 1.27 0.019 0.050 M S 0.62 0.024 8 (max.) P013H 7/9 74VHC257 TSSOP16 MECHANICAL DATA mm DIM. MIN. inch TYP. A MAX. MIN. 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 0.20 0.0035 0.0079 D 4.9 5 5.1 0.193 0.197 0.201 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 e K c E1 PIN 1 IDENTIFICATION 1 L E D 8/9 TYP. 74VHC257 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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