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Details, datasheet, quote on part number:74VHC157MTCX
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Datasheet text preview:
74VHC157 Quad 2-Input Multiplexer
November 1992 Revised April 1999
74VHC157 Quad 2-Input Multiplexer
General Description
The VHC157 is an advanced high speed CMOS Quad 2Channel Multiplexer fabricated with silicon gate CMOS technology. It achieves the high speed operation similar to equivalent Bipolar Schottky TTL while maintaining the CMOS low power dissipation. It consists of four 2-input digital multiplexers with common select and enable inputs. When the ENABLE input is held "H" level, selection of data is inhibited and all the outputs become "L" level. The SELECT decoding determines whether the I0x or I1x inputs get routed to their corresponding outputs. An Input protection circuit ensures that 0V to 7V can be applied to the input pins without regard to the supply voltage. This device can be used to interface 5V to 3V systems and on two supply systems such as battery back up. This circuit prevents device destruction due to mismatched supply and input voltages.
Features
s High Speed: tPD = 4.1 ns (typ) at VCC = 5V s Low power dissipation: ICC = 4 µA (max.) at TA = 25°C s High noise immunity: VNIH = VNIL = 28% VCC (min.) s Power down protection is provided on all inputs s Low noise: VOLP = 0.8V (max.) s Pin and function compatible with 74HC157
Ordering Code:
Order Number 74VHC157M 74VHC157SJ 74VHC157MTC 74VHC157N Package Number M16A M16D MTC16 N16E Package Description 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150" Narrow 16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide 16-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide
Surface mount packages are also available on Tape and Reel. Specify by appending the suffix letter "X" to the ordering code.
Logic Symbols
Connection Diagram
IEEE/IEC
Pin Descriptions
Pin Names I0aI0d I1aI1d E S ZaZd Description Source 0 Data Inputs Source 1 Data Inputs Enable Input Select Input Outputs
© 1999 Fairchild Semiconductor Corporation
DS011536.prf
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74VHC157
Truth Table
Inputs E H L L L L S X H H L L I0 X X X L H I1 X L H X X Outputs Z L L H L H
Functional Description
The VHC157 is a quad 2-input multiplexer. It selects four bits of data from two sources under the control of a common Select input (S). The Enable input (E) is active-LOW. When E is HIGH, all of the outputs (Z) are forced LOW regardless of all other inputs. The VHC157 is the logic implementation of a 4-pole, 2-position switch where the position of the switch is determined by the logic levels supplied to the Select input. The logic equations for the outputs are shown below: Za = E · (I1a · S + I0a · S) Zb = E · (I1b · S + I0b · S) Zc = E · (I1c · S + I0c · S) Zd = E · (I1d · S + I0d · S) A common use of the VHC157 is the moving of data from two groups of registers to four common output busses. The particular register from which the data comes is determined by the state of the Select input. A less obvious use is as a function generator. The VHC157 can generate any four of the sixteen different functions of two variables with one variable common. This is useful for implementing gating functions.
H = HIGH Voltage Level L = LOW Voltage Level X = Immaterial
Logic Diagram
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.
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74VHC157
Absolute Maximum Ratings(Note 1)
Supply Voltage (VCC) DC Input Voltage (VIN) DC Output Voltage (VOUT) Input Diode Current (IIK) Output Diode Current (IOK) DC Output Current (IOUT) DC VCC /GND Current (ICC ) Storage Temperature (TSTG) Lead Temperature (TL) (Soldering, 10 seconds) 260°C -0.5V to +7.0V -0.5V to +7.0V -0.5V to VCC + 0.5V -20 mA ±20 mA ±25 mA ±50 mA -65°C to +150°C
Recommended Operating Conditions (Note 2)
Supply Voltage (VCC) Input Voltage (VIN) Output Voltage (VOUT) Operating Temperature (TOPR) Input Rise and Fall Time (tr, tf) VCC = 3.3V ± 0.3V VCC = 5.0V ± 0.5V 0 100 ns/V 0 20 ns/V 2.0V to +5.5V 0V to +5.5V 0V to VCC -40°C to +85°C
Note 1: Absolute Maximum Ratings are values beyond which the device may be damaged or have its useful life impaired. The databook specifications should be met, without exception, to ensure that the system design is reliable over its power supply, temperature, and output/input loading variables. Fairchild does not recommend operation outside databook specifications. Note 2: Unused inputs must be held HIGH or LOW. They may not float.
DC Electrical Characteristics
Symbol VIH VIL VOH Parameter HIGH Level Input Voltage LOW Level Input Voltage HIGH Level Output Voltage V CC (V) 2.0 3.0 - 5.5 2.0 3.0 - 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 IIN ICC Input Leakage Current Quiescent Supply Current 0 - 5.5 5.5 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 ±0.1 4.0 2.0 3 .0 4.5 TA = 25°C Min 1 .50 0.7 VCC 0.50 0.3 VCC 1 .9 2.9 4 .4 2 .48 3 .80 0 .1 0.1 0 .1 0 .44 0 .44 ±1.0 40.0 V µA µA IOL = 4 mA IOL = 8 mA VIN = 5.5V or GND VIN = VCC or GND V V IOH = -4 mA IOH = -8 mA VIN = VIH IOL = 50 µA or VIL V Typ Max TA = -40°C to +85°C M in 1 .50 0.7 VCC 0 .50 0.3 VCC Max Units V V VIN = VIH IOH = -50 µA or VIL Conditions
Noise Characteristics
Symbol VOLP (Note 3) VOLV (Note 3) VIHD (Note 3) VILD (Note 3) Parameter Quiet Output Maximum Dynamic VOL Quiet Output Minimum Dynamic VOL Minimum HIGH Level Dynamic Input Voltage Maximum LOW Level Dynamic Input Voltage 5.0 1.5 V CL = 50 pF 5.0 3.5 V CL = 50 pF 5 .0 -0.3 -0.8 V CL = 50 pF V CC (V) 5 .0 TA = 25°C Typ 0.3 Limits 0.8 Units V CL = 50 pF Conditions
Note 3: Parameter guaranteed by design.
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74VHC157
AC Electrical Characteristics
Symbol tPLH tPHL Parameter Propagation Delay In to Zn 5.0 ± 0.5 tPLH tPHL Propagation Delay S to Zn 5.0 ± 0.5 tPLH tPHL Propagation Delay E to Zn 5.0 ± 0.5 CIN CPD Input Capacitance Power Dissipation Capacitance
Note 4: CPD is defined as the value of the internal equivalent capacitance which is calculated from the operating current consumption without load. Average operating current can be obtained by the equation: ICC (opr.) = CPD * VCC * fIN + ICC.
VCC (V) 3.3 ± 0.3
TA = 25°C Min Typ 6 .2 8.7 4 .1 5 .6 8 .4 10.9 5 .3 6.8 8 .7 11.2 5 .6 7.1 4 20 Max 9.7 13.2 6.4 8 .4 13.2 16.7 8.1 10.1 13.6 17.1 8.6 10.6 10
TA = -40°C to +85°C M in 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Max 11.5 15.0 7.5 9 .5 15.5 19.0 9.5 11.5 16.0 19.5 10.0 12.0 10
Units ns ns ns ns ns ns pF pF
Conditions CL = 15 pF CL = 50 pF CL = 15 pF CL = 50 pF CL = 15 pF CL = 50 pF CL = 15 pF CL = 50 pF CL = 15 pF CL = 50 pF CL = 15 pF CL = 50 pF VCC = Open (Note 4)
3.3 ± 0.3
3.3 ± 0.3
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74VHC157
Physical Dimensions inches (millimeters) unless otherwise noted
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150" Narrow Package Number M16A
16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide Package Number M16D
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