74VHCT257A QUAD 2 CHANNEL MULTIPLEXER (3-STATE) PRELIMINARY DATA ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ HIGH SPEED: tPD = 5.8 ns (TYP.) at VCC = 5V LOWPOWER DISSIPATION: ICC = 4 µA (MAX.) at TA = 25 oC COMPATIBLE WITH TTL OUTPUTS: VIH = 2V (MIN), VIL = 0.8V (MAX) POWER DOWN PROTECTION ON INPUTS & OUTPUTS SYMMETRICAL OUTPUT IMPEDANCE: |IOH| = IOL = 8 mA (MIN) BALANCED PROPAGATION DELAYS: tPLH ≅ tPHL OPERATING VOLTAGE RANGE: VCC (OPR) = 4.5V to 5.5V PIN AND FUNCTION COMPATIBLE WITH 74 SERIES 257 IMPROVED LATCH-UP IMMUNITY LOWNOISE: VOLP = 0.8V (Max.) DESCRIPTION The 74VHCT257A 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. SOP TSSOP ORDER CODES PACKAGE T UBE T& R SOP 74VHCT257AM 74VHCT257AMTR TSSOP 74VHCT257ATTR The 74VHCT257A 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 output 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 March 2000 1/9 74VHCT257A 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 Inputs 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 Input (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 74VHCT257A ABSOLUTE MAXIMUM RATINGS Symbol VCC Parameter Supply Voltage Value Unit -0.5 to +7.0 V VI DC Input Voltage -0.5 to +7.0 V VO DC Output Voltage (see note 1) -0.5 to +7.0 V VO DC Output Voltage (see note 2) -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 ± 50 mA ICC or IGND DC VCC or Ground Current 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. 1) Output in OFF State 2) High or Low State RECOMMENDED OPERATING CONDITIONS Symbol VCC Parameter Supply Voltage Valu e Unit 4.5 to 5.5 V VI Input Voltage 0 to 5.5 V VO Output Voltage (see note 1) 0 to 5.5 V VO Output Voltage (see note 2) Top Operating Temperature dt/dv Input Rise and Fall Time (see note 3) (V CC = 5.0 ± 0.5V) 0 to VCC -40 to +85 0 to 20 V o C ns/V 1) Output in OFF State 2) High or Low State 3)VIN from0.8V to 2 V 3/9 74VHCT257A DC SPECIFICATIONS Symb ol Parameter T est Cond ition s Min. 2 VIH High Level Input Voltage 4.5 to 5.5 VIL Low Level Input Voltage 4.5 to 5.5 VOH High Level Output Voltage VOL IOZ II Value T A = 25 o C V CC (V) Typ . Un it -40 to 85 o C Max. Min . Max. 2 0.8 V 0.8 V 4.5 I O =-50 µA 4.4 4.5 IO=-8 mA 3.94 Low Level Output Voltage 4.5 I O=50 µA 0.1 0.1 4.5 IO=8 mA 0.36 0.44 High Impedance Output Leakage Current 4.5 to 5.5 VI = VIH or VIL VO = 0V to 5.5V ±0.25 ±2.5 µA 0 to 5.5 VI = 5.5V or GND ±0.1 ±1.0 µA Input Leakage Current 4.5 4.4 V 3.8 0.0 V ICC Quiescent Supply Current 5.5 VI = VCC or GND 4 40 µA ∆ICC Additional Worst Case Supply Current 5.5 One Input at 3.4V, other input at VCC or GND 1.35 1.5 mA IOPD Output Leakage Current 0 VOUT = 5.5V 0.5 5.0 µA AC ELECTRICAL CHARACTERISTICS (Input t r = tf =3 ns) Symb ol Parameter V CC (V) (*) tPLH tPHL Propagation Delay Time A, B to Y 5.0 5.0(*) 15 tPLH tPHL Propagation Delay Time SELECT to Y 5.0(*) 5.0(*) 15 tPZL tPZH Output Enable Time tPLZ tPHZ Output Disable Time (*) Voltage range is 5V ± 0.5V 4/9 Test Co ndition CL (pF ) Value T A = 25 o C Min. Typ . Max. Un it -40 to 85 o C Min . Max. 5.8 8.3 9.3 12.8 1.0 1.0 11.0 14.5 ns 50 7.0 9.5 11.0 14.5 1.0 1.0 13.0 16.5 ns 5.0(*) 15 6.7 10.5 1.0 12.5 5.0(*) 5.0(*) 50 9.2 8.6 14.0 12.0 1.0 1.0 16.0 13.5 50 50 ns ns 74VHCT257A 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) 23 pF C IN 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/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 o Min. -0.8 C L = 50 pF Un it o T A = 25 C V CC (V) -40 to 85 C Typ . Max. 0.3 0.8 Min . Max. -0.3 2.0 V 0.8 1) Worst case package. 2) Max number of outputs defined as (n). Data inputs are driven 0V to 3.0V, (n -1) outputs switching and one output at GND. 3) Max number of data inputs (n) switching. (n-1) switching 0V to3.0V. Inputs under test switching: 3.0V 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) 5/9 74VHCT257A WAVEFORM 1: PROPAGATION DELAYS FOR INVERTING CONDITIONS (f=1MHz; 50% duty cycle) WAVEFORM 2: PROPAGATION DELAYS FOR NON-INVERTING CONDITIONS (f=1MHz; 50% duty cycle) 6/9 74VHCT257A WAVEFORM 3: OUTPUT ENABLE AND DISABLE TIME (f=1MHz; 50% duty cycle) 7/9 74VHCT257A 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 8/9 74VHCT257A TSSOP16 MECHANICAL DATA mm DIM. MIN. inch TYP. A MAX. 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 0.20 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 L E D E1 PIN 1 IDENTIFICATION 1 9/9 74VHCT257A Information furnished is believed to be accurate and reliable. However, STMicroelectronic s 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. STMicroelectronics products are not authorized for use as critical components in life support devices or systems withoutexpress written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics 2000 STMicroelectronics – Printed in Italy – All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com . 10/9