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IDTQS3251
HIGH-SPEED CMOS QUICKSWITCH 8:1 MUX/DEMUX INDUSTRIAL TEMPERATURE RANGE
FEBRUARY 2000
1999 Integrated Device Technology, Inc. DSC-5754/-c
IDTQS3251
INDUSTRIAL TEMPERATURE RANGE
QUICKSWITCH® PRODUCTS
HIGH-SPEED CMOS
QUICKSWITCH 8:1 MUX/DEMUX
DESCRIPTION:
The QS3251 is a high-speed CMOS TTL-compatible 8:1 multiplexer/
demultiplexer. The QS3251 has 3-state outputs. The QS3251 is a function
and pinout compatible version of the 74F251, 74FCT251 and the 74ALS/
AS/LS251 8:1 multiplexers. The low ON resistance of the QS3251 allows
inputs to be connected to outputs without adding propagation delay and
without generating additional ground bounce noise.
Mux/Demux devices provide an order of magnitude faster speed than
equivalent logic devices.
The QS3251 is characterized for operation at -40°C to +85°C.
S0
Y
I0
I1
I2
I3
I4
I5
I6
I7
S1
S2
E
FUNCTIONAL BLOCK DIAGRAM
FEATURES:
− Enhanced N channel FET with no inherent diode to Vcc
− 5Ω bidirectional switches connect inputs to outputs
− Pin compatible with the 74F251, 74FCT251, and 74FCT251T
− Zero propagation delay, zero ground bounce
− Undershoot clamp diodes on all switch and control inputs
− TTL-compatible control inputs
− Available in QSOP and SOIC Packages
APPLICATIONS
− Logic replacement
− Video, audio, graphics switching, muxing
− Hot-swapping, hot-docking
− Voltage translation (5V to 3.3V)
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INDUSTRIAL TEMPERATURE RANGE
IDTQS3251
HIGH-SPEED CMOS QUICKSWITCH 8:1 MUX/DEMUX
PIN CONFIGURATION
SOIC/ QSOP
TOP VIEW
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
I3
I2
I1
I0
Y
GND
VCC
S0
NC
ES1
S2
I4
I5
I6
I7
SO16-1
SO16-7
PIN DESCRIPTION
Pin Names I/O Description
I0 - I7I Data Inputs
S0 - S2I Select Inputs
EI Enable Input
Y O Data Output
ABSOLUTE MAXIMUM RATINGS (1)
Symbol Description Max. Unit
VTERM(2) Supply Voltage to Ground – 0.5 to +7 V
VTERM(3) DC Switch Voltage VS– 0.5 to +7 V
VTERM(3) DC Input Voltage VIN – 0.5 to +7 V
VAC AC Input Voltage (pulse width ≤20ns) -3 V
IOUT DC Output Current 120 mA
PMAX Maximum Power Dissipation (TA = 85°C) 0.5 W
TSTG Storage Temperature – 65 to +150 °C
NOTES:
1. Stresses greater than those listed under ABSOLUTE MAXIMUM
RATINGS may cause permanent damage to the device. This is a
stress rating only and functional operation of the device at these or
any other c onditions above t hose indic ated in t he operational sections
of this specification is not implied. Exposure to absolute maximum
rating condit i ons for extended periods may affect reliabilit y .
2. V cc Terminal s.
3. A l l terminals except V cc.
CAPACITANCE
(TA = +25OC, f = 1.0MHz, VIN = 0V, VOUT = 0V)
Pins Typ. Max. (1) Unit
Control Pins 4 5 pF
Quickswitch Channels Demux 5 7 pF
(Switch OFF) Mux 21 23 pF
NOTE:
1. This paramet er i s guaranteed but not produc tion tested.
FUNCTION TABLE(1)
Select
ES
2S
1S
0Y Function
H X X X Hi-Z Disable
LL L L I
0S
2 - S 0 = 0
LL LH I
1S
2 - S 0 = 1
LL HL I
2S
2 - S 0 = 2
LL HH I
3S
2 - S 0 = 3
LH L L I
4S
2 - S 0 = 4
LH L H I
5S
2 - S 0 = 5
LH H L I
6S
2 - S 0 = 6
LH HH I
7S
2 - S 0 = 7
NOTE:
1. H
=
HIGH Volta
g
e Level
L
=
LOW Volta
g
e Level
X
=
Don’t Care
Z
=
Hi
g
h-Impedence
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IDTQS3251
HIGH-SPEED CMOS QUICKSWITCH 8:1 MUX/DEMUX INDUSTRIAL TEMPERATURE RANGE
RON
(ohms)
VIN
(Volts)
TYPICAL ON RESISTANCE vs VIN AT VCC = 5V
16
14
12
10
8
6
4
2
00.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: TA = -40°C to +85°C, VCC = 5.0V ± 5%
Symbol Parameter Test Conditions Min. Typ.(1) Max. Unit
VIH Input HIGH Voltage Guaranteed Logic HIGH for Control Pins 2 — — V
VIL Input LOW Voltage Guaranteed Logic LOW for Control Pins — — 0.8 V
IIN Input Leakage Current (Control Inputs) (2) 0V ≤ VIN ≤ Vcc ——±1
µA
I
OZ Off-State Current (Hi-Z) 0V ≤ VOUT ≤ Vcc ——±1
µA
R
ON Switch ON Resistance Vcc = Min., VIN = 0V, ION = 30mA —5 7Ω
R
ON Switch ON Resistance Vcc = Min., VIN = 2.4V, ION = 15mA —1015Ω
V
PPass Voltage (2) VIN = Vcc = 5V, IOUT = -5µA3.7 4 4.2 V
NOTES:
1. Typical values are at V CC = 5.0V, TA = 25°C.
2. P ass vol tage is guarant eed but not producti on tested.
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INDUSTRIAL TEMPERATURE RANGE
IDTQS3251
HIGH-SPEED CMOS QUICKSWITCH 8:1 MUX/DEMUX
POWER SUPPLY CHARACTERISTICS
Symbol Parameter Test Conditions(1) Max. Unit
ICCQ Quiescent Power Supply Current VCC = Max., VIN = GND or Vcc, f = 0 3 µA
∆ICC Power Supply Current per Control Input HIGH (2) VCC = Max., VIN = 3.4V, f = 0 1.5 mA
ICCD Dynamic Power Supply Current per MHz(3) VCC = Max., I and Y pins open
Control Inputs Toggling at 50% Duty Cycle 0.25 mA/MHz
NOTES:
1. For conditions shown as M i n. or Max. , use the appropri at e values s pecified under DC Elect ri cal Charact eri s tics .
2. Per TLL driven input (VIN = 3.4V, control i nput s only). I and Y pins do not contri bute to ∆Icc.
3. This current applies to the control inputs only and represents the current required to switch internal capacitance at the specified frequency. The I
and Y inputs generate no significant AC or DC currents as they transiti on. This param et er i s guaranteed but not producti on t ested.
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
TA = -40°C to +85°C, VCC = 5.0V ± 5%
CLOAD = 50pF, RLOAD = 500Ω unless otherwise noted.
Symbol
Parameter Min. (1) Typ. Max. Unit
tPLH
tPHL Data Propagation Delay (2,3)
In to Y — — 0.25 ns
tPZL
tPZH Switch Turn-on Delay
Sn to Y 0.5 — 6.6 ns
tPZL
tPZH Switch Turn-on Delay
E to Y 0.5 — 6 ns
tPLZ
tPHZ Switch Turn-off Delay (2)
E to Y, Sn to Y 0.5 — 6 ns
NOTES:
1. M i ni m um s are guaranteed but not production t ested.
2. This parameter i s guaranteed but not production t ested.
3. The bus switc h contributes no propagation del ay other than the RC del ay of the ON res i stance of the swi t ch and the load c ap acitanc e. The time
const ant for the swi t ch alone is of the order of 0.25ns for CL = 50pF. Since this t i m e constant is much smal l er t han the rise and f al l times of typi cal
driving s i gnal s, it adds very li t tle propagation del ay to the system. Propagation delay of the bus switc h, when used in a system, is determined by the
driving c i rcuit on t he dri v i ng side of t he switc h and i t s interac tion with the load on the driven side.
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IDTQS3251
HIGH-SPEED CMOS QUICKSWITCH 8:1 MUX/DEMUX INDUSTRIAL TEMPERATURE RANGE
ORDERING INFORMATION
IDTQS XXXXX XX
Package
D e vice Ty pe
Small Outline IC (SO1 6-1 )
Qua rter S ize Outline P ackage (SO 16-7)
S1
Q
3251 H igh Sp eed C MO S Q uickswitch 8:1 Mux/Demux
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