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(R)
74VHC257
QUAD 2 CHANNEL MULTIPLEXER (3-STATE)
s s
s
s s
s
s
s
s s
HIGH SPEED: tPD = 3.7 ns (TYP.) at VCC = 5V LOWPOWER DISSIPATION: ICC = 4 A (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.)
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.
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.
PIN CONNECTION AND IEC LOGIC SYMBOLS
June 1999
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INPUT EQUIVALENT CIRCUIT PIN DESCRIPTION
PIN No 1 2, 5, 14, 11 3, 6, 13, 10 4, 7, 12, 9 15 8 16 SYMBOL SELECT 1A to 4A 1B to 4B 1Y to 4Y OE GND VCC NAME AND FUNCT ION Common Data Select Input Data Input From Source A Data Inputs from Source B 3 State Multiplexer Outputs 3 State Output Enable Inputs (Active LOW) Ground (0V) Positive Supply Voltage
TRUTH TABLE
INPUT S OE H L L L L
X = DON'T CARE Z = HIGH IMPEDANCE
OUTPUTS A X L H X X B X X X L H Y Z L H L H
SELE CT X L L H H
LOGIC DIAGRAM
Thislogic diagram has notbe used to estimate propagation delays
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ABSOLUTE MAXIMUM RATINGS
Symbol VCC VI VO IIK IOK IO Tstg TL Supply Voltage DC Input Voltage DC Output Voltage DC Input Diode Current DC Output Diode Current DC Output Current Storage Temperature Lead Temperature (10 sec) Parameter Value -0.5 to +7.0 -0.5 to +7.0 -0.5 to VCC + 0.5 - 20 20 25 50 -65 to +150 300 Unit V V V mA mA mA mA
o o
ICC or IGND DC VCC or Ground Current
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 VI VO Top dt/dv Supply Voltage Input Voltage Output Voltage Operating Temperature Input Rise and Fall Time (see note 1) (VCC = 3.3 0.3V) (V CC = 5.0 0.5V) Parameter Valu e 2.0 to 5.5 0 to 5.5 0 to VCC -40 to +85 0 to 100 0 to 20 Unit V V V
o
C
ns/V ns/V
1) VIN from 30% to70%of VCC
DC SPECIFICATIONS
Symb ol Parameter T est Cond ition s V CC (V) VIH VIL VOH High Level Input Voltage Low Level Input Voltage High Level Output Voltage 2.0 3.0 to 5.5 2.0 3.0 to 5.5 2.0 3.0 4.5 3.0 4.5 VOL Low Level Output Voltage 2.0 3.0 4.5 3.0 4.5 IOZ High Impedance Output Leakage Current Input Leakage Current Quiescent Supply Current 5.5 0 to 5.5 5.5 I O =-50 A IO=-50 A IO=-50 A IO=-4 mA IO=-8 mA I O=50 A IO=50 A IO=50 A IO=4 mA IO=8 mA VI = VIH or VIL VO = VCC or GND VI = 5.5V or GND VI = VCC or GND 1.9 2.9 4.4 2.58 3.94 0.0 0.0 0.0 0.1 0.1 0.1 0.36 0.36 0.25 2.0 3.0 4.5
o
Value T A = 25 C Min. 1.5 0.7VCC 0.5 0.3VCC 1.9 2.9 4.4 2.48 3.8 0.1 0.1 0.1 0.44 0.44 2.5 Typ . Max. -40 to 85 C Min . 1.5 0.7VCC 0.5 0.3VCC Max.
o
Un it
V V
V
V
A
II ICC
0.1 4
1.0 40
A A
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AC ELECTRICAL CHARACTERISTICS (Input t r = tf =3 ns)
Symb ol Parameter V CC (V) tPLH tPHL Propagation Delay Time A, B to Y Test Co ndition CL (pF ) 15 50 15 50 15 50 15 50 15 50 15 50 50 50 Value T A = 25 o C Min. Typ . Max. 5.8 9.3 8.3 3.6 5.1 7.0 9.5 4.0 5.5 6.7 9.2 3.6 5.1 8.6 5.7 12.8 5.9 7.9 11.0 14.5 6.8 8.8 10.5 14.0 6.8 8.8 12.0 7.9 Un it -40 to 85 o C Min . Max. 1.0 11.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 14.5 7.0 9.0 13.0 16.5 8.0 10.0 12.5 16.0 8.0 10.0 13.5 9.0 ns ns
3.3(*) 3.3(*) 5.0(**) 5.0(**) 3.3(*) 3.3(*) 5.0 5.0(**) 3.3 3.3(*) 5.0(**) 5.0(**) 3.3(*) 5.0
(**) (*) (**)
tPLH tPHL
Propagation Delay Time SELECT to Y
ns
tPZL tPZH
Output Enable Time
tPLZ tPHZ
Output Disable Time
ns
(*) Voltage range is 3.3V 0.3V (**) Voltage range is 5V 0.5V
CAPACITIVE CHARACTERISTICS
Symb ol Parameter T est Cond ition s Min. C IN COUT CPD Input Capacitance Output Capacitance Power Dissipation Capacitance (note 1) Typ . 4 6 23 Value T A = 25 o C Max. 10 -40 to 85 o C Min . Max. 10 pF pF pF Un it
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 V CC (V) VOLP VOLV VIHD VILD Dynamic Low Voltage Quiet Output (note 1, 2) Dynamic High Voltage Input (note 1, 3) Dynamic Low Voltage Input (note 1, 3) 5.0 -0.8 5.0 5.0 C L = 50 pF 3.5 1.5 Min. Typ . 0.3 -0.3 V Value T A = 25 o C Max. 0.8 -40 to 85 o C Min . Max. Un it
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.
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TEST CIRCUIT
T EST tPLH , tPHL tPZL , tPLZ tPZH , tPHZ
CL = 15/50 pF or equivalent (includes jig and probe capacitance) RL = R1 = 1K orequivalent RT = ZOUT of pulse generator (typically 50)
SW IT CH Open VCC GND
WAVEFORM 1: PROPAGATION DELAYS FOR INVERTING CONDITIONS (f=1MHz; 50% duty cycle)
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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)
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SO-16 MECHANICAL DATA
DIM. MIN. A a1 a2 b b1 C c1 D E e e3 F G L M S 3.8 4.6 0.5 9.8 5.8 1.27 8.89 4.0 5.3 1.27 0.62 8 (max.) 0.149 0.181 0.019 10 6.2 0.35 0.19 0.5 45 (typ.) 0.385 0.228 0.050 0.350 0.157 0.208 0.050 0.024 0.393 0.244 0.1 mm TYP. MAX. 1.75 0.2 1.65 0.46 0.25 0.013 0.007 0.019 0.004 MIN. inch TYP. MAX. 0.068 0.007 0.064 0.018 0.010
P013H
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TSSOP16 MECHANICAL DATA
mm MIN. A A1 A2 b c D E E1 e K L 0o 0.50 0.05 0.85 0.19 0.09 4.9 6.25 4.3 5 6.4 4.4 0.65 BSC 4o 0.60 8o 0.70 0o 0.020 0.10 0.9 TYP. MAX. 1.1 0.15 0.95 0.30 0.20 5.1 6.5 4.48 0.002 0.335 0.0075 0.0035 0.193 0.246 0.169 0.197 0.252 0.173 0.0256 BSC 4o 0.024 8o 0.028 0.004 0.354 MIN. inch TYP. MAX. 0.433 0.006 0.374 0.0118 0.0079 0.201 0.256 0.176
DIM.
A
A2 A1 b e K c L E
D
E1
PIN 1 IDENTIFICATION
1
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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. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a trademark of STMicroelectronics (c) 1999 STMicroelectronics - Printed in Italy - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - France - Germany - Italy - Japan - Korea - Malaysia - Malta - Mexico - Morocco - The Netherlands Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A. http://www.st.com .
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