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IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
INDUSTRIAL TEMPERATURE RANGE
NOVEMBER 1999
1999 Integrated Device Technology, Inc.
DSC-5578/-
c
IDTQS34XS257
INDUSTRIAL TEMPERATURE RANGE
QUICKSWITCH
PRODUCTS
HIGH-SPEED CMOS
SYNCHROSWITCHTM
32:16 MUX/DEMUX
DESCRIPTION:
The QS34XS257 is a high-speed CMOS quad 32:16 multiplexer/
demultiplexer. It is organized as four independent quad 2:1 mux/demux
blocks. Port selection and connection, controlled by SEL signals, can be
either asynchronous or synchronous. In the synchronous mode, the A or
B port to Y port connection is updated on the rising edge of the input clock
CLK. Once the port-to-port connection is made, data flow can be bi-
directional with a typical 250ps propagation delay through the switch. Clock
Enable, overriding Asynchronous Enable, and Asynchronous Select
controls provide additional design flexibility.
Synchronous controls ease timing constraints in many high speed data
mux/demux applications, such as bank interleaving. The QS34XS257 is
available in the space-saving, 80-pin dual-in-line MillipaQ package.
The QS34XS257 is characterized for operation at -40C to +85C.
SELn
CLKn
CLKENn
OEn
SYNCn
Yn
0
Yn
1
Yn
2
Yn
3
An
0
Bn
0
An
1
An
2
An
3
Bn
1
Bn
2
Bn
3
CONTROL
LOGIC
NOTE: One of four blocks shown.
FUNCTIONAL BLOCK DIAGRAM
FEATURES:
-
Enhanced N channel FET with no inherent diode to Vcc
-
Bidirectional signal flow
-
Flow-through pinout
-
Zero propagation delay, zero ground bounce
-
16 banks of 2:1 Mux/Demux
-
Port select synchronous to the clock
-
Clock enable and Asynchronous enable
-
Undershoot clamp diodes on all switch and control pins
-
Asynchronous SEL option
-
Break-before-make feature
-
Available in 80-pin MillipaQ (Q3)
-
Bus-hold eliminates floating bus lines and reduces static power
consumption
APPLICATIONS:
-
Memory Interleaving
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INDUSTRIAL TEMPERATURE RANGE
IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
NC
A
00
A
01
A
02
A
03
B
00
B
01
B
02
B
03
G ND
NC
A
10
A
11
A
12
A
13
B
10
B
11
B
12
B
13
NC
A
20
A
21
A
22
A
23
B
20
B
21
B
22
B
23
G ND
NC
A
30
A
31
A
32
A
33
B
30
B
31
B
32
B
33
G ND
G ND
2
3
4
5
6
7
8
73
74
75
76
77
78
79
80
1
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
56
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
39
38
37
36
35
34
33
32
31
30
29
28
27
26
40
25
58
59
60
61
62
63
64
65
66
67
68
69
70
71
57
72
Vcc
O E
0
SEL
0
Y
00
Y
01
Y
02
Y
03
CLKEN
0
CLK
0
SYN C
0
Vcc
O E
1
SEL
1
Y
10
Y
11
Y
12
Y
13
CLKEN
1
CLK
1
SYN C
1
Vcc
O E
2
SEL
2
Y
20
Y
21
Y
22
Y
23
CLKEN
2
CLK
2
SYN C
2
Vcc
O E
3
SEL
3
Y
30
Y
31
Y
32
Y
33
CLKEN
3
CLK
3
SYN C
3
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
Description
Max.
Unit
V
TERM(2)
Supply Voltage to Ground
0.5 to +7
V
V
TERM(3)
DC Switch Voltage V
S
0.5 to +7
V
V
TERM(3)
DC Input Voltage V
IN
0.5 to +7
V
V
AC
AC Input Voltage (pulse width
20ns)
-3
V
I
OUT
DC Output Current
120
mA
P
MAX
Maximum Power Dissipation (T
A
= 85
C)
1.16
W
T
STG
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 conditions above those indicated in the operational sections
of this specification is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect reliability.
2. Vcc Terminals.
3. All terminals except Vcc.
CAPACITANCE
(T
A
= +25
O
C, f = 1.0MHz, V
IN
= 0V, V
OUT
= 0V)
Pins
Typ.
Max.
(1)
Unit
Control Inputs
4
5
pF
Quickswitch Channels
Demux
5
7
pF
(Switch OFF)
Mux
7
9
pF
NOTE:
1. This parameter is guaranteed at characterization but not tested.
PIN DESCRIPTION
Pin Names
I/O
Description
An
0
- An
3
I/O
Demux Port A
Bn
0
- Bn
3
I/O
Demux Port B
Yn
0
- Yn
3
I/O
Mux Port Y
SELn
I
Select Input
CLKn
I
Clock
CLKENn
I
Clock Enable
OEn
I
Output Enable
SYNCn
I
Synchronous Selection Enable
MILLIPAQ
TOP VIEW
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IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
INDUSTRIAL TEMPERATURE RANGE
FUNCTION TABLE
(1)
Control Inputs
Port Status
Function
SYNC
OEn
CLKn
CLKENn
SELn
Yn
0
Yn
1
Yn
2
Yn
3
L
L
L
L
An
0
An
1
An
2
An
3
Select Port A
L
L
L
H
Bn
0
Bn
1
Bn
2
Bn
3
Select Port B
L
H
L
X
No change in Mux connection
Switch OFF
(2)
L
L
H
X
No change in Mux connection
Hold Previous Mux connection
(3)
(Switch ON)
L
H
H
X
No change in Mux connection
Switch OFF
(4)
H
L
X
X
L
An
0
An
1
An
2
An
3
Select Port A
H
L
X
X
H
Bn
0
Bn
1
Bn
2
Bn
3
Select Port B
H
H
X
X
X
No change in Mux connection
Hold Previous Data (Switch OFF)
NOTES:
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don't Care
= Low-to-High Transition
2. Mux switches are turned off. The port connection can be changed by the SEL input.
3. The contents of the "Mux select register" are unchanged and the previous Mux connection is unchanged. The output (Mux port) data state will
depend on the present data state of the input (Demux port).
4. The contents of the "Mux select register" are unchanged.
1
2:1
M U X
0
SE Ln
C LK EN n
C LK n
SYN C n
O En
0
2:1
M U X
1
D
Q
To Port B Sw itches
To Port A Sw itches
CONTROL LOGIC
(1)
NOTE:
1. One of four blocks.
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INDUSTRIAL TEMPERATURE RANGE
IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
TYPICAL ON RESISTANCE vs V
IN
AT V
CC
= 5V
R
ON
(ohms)
V
IN
(Volts)
16
14
12
10
8
6
4
2
0
0.0
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: T
A
= -40C to +85C, V
CC
= 5.0V 10%
Symbol
Parameter
Test Conditions
Min.
Typ.
(1)
Max.
Unit
V
IH
Input HIGH Voltage
Guaranteed Logic HIGH for Control Pins
2
--
--
V
V
IL
Input LOW Voltage
Guaranteed Logic LOW for Control Pins
--
--
0.8
V
I
IN
Input Leakage Current (Control Inputs)
0V
V
IN
Vcc
--
0.1
1
A
R
ON
Switch ON Resistance
(2)
Vcc = Min., V
IN
= 0V
,
I
ON
= 30mA
--
7
9
Vcc = Min., V
IN
= 2.4V
,
I
ON
= 15mA
--
10
13
NOTES:
1. Typical values are at V
CC
= 5.0V, T
A
= 25C.
2. Measured by voltage drop between A/B and Y pin at indicated current through the switch.
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IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
INDUSTRIAL TEMPERATURE RANGE
POWER SUPPLY CHARACTERISTICS
Symbol
Parameter
Test Conditions
(1)
Max.
Unit
I
CCQ
Quiescent Power Supply Current
V
CC
= Max., V
CTRL
= GND or Vcc, f = 0
12
mA
I
CC
Power Supply Current per Control Input HIGH
(2)
V
CC
= Max., V
IN
= 3.4V, f = 0
1.5
mA
I
CCD
Dynamic Power Supply Current per MHz
(3)
V
CC
= Max., A/B and Y pins open
Control Input Toggling at 50% Duty Cycle
0.25
mA/MHz
NOTES:
1. For conditions shown as Min. or Max., use the appropriate values specified under DC Electrical Characteristics.
2. Per TLL driven control inputs. A/B and Y pins do not contribute 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 A/B
and Y inputs generate no significant AC or DC currents as they transition. This parameter is guaranteed but not production tested.
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
T
A
= -40C to +85C, V
CC
= 5.0V 10%
C
LOAD
= 50pF, R
LOAD
= 500
unless otherwise noted.
Symbol
Parameter
Min.
Typ.
Max.
Unit
t
PLH
t
PHL
Data Propagation Delay
(1,2)
A/B to Y, Y to A/B
--
0.25
--
ns
t
SEC
Clock Enable to Clock Setup Time
3
--
--
ns
t
HEC
Clock Enable to Clock Hold Time
0
--
--
ns
t
CSO
Clock to A, B Switch Turn-On Delay
(3)
0.5
--
7
ns
t
ASO
Asynchronous Select to A, B Switch Turn-On Delay
(3)
0.5
--
7
ns
t
W
Clock Pulse Width HIGH
3
--
--
ns
t
SCS
Clock to SEL Setup Time
3
--
--
ns
t
HCS
Clock to SEL Hold Time
0
--
--
ns
t
PZL
t
PZH
Asynchronous Enable to Switch Turn-On Delay
(3)
1.5
--
5.2
ns
t
PLZ
t
PHZ
Asynchronous Enable to Switch Turn-Off Delay
(1,3)
1.5
--
4.8
ns
NOTES:
1. This parameter is guaranteed but not tested.
2. The bus switch contributes no propagation delay other than the RC delay of the ON resistance of the switch and the load capacitance. The time
constant for the switch alone is of the order of 0.25ns for C
L
= 50pF. Since this time constant is much smaller than the rise and fall times of typical
driving signals, it adds very little propagation delay to the system. Propagation delay of the bus switch, when used in a system, is determined by the
driving circuit on the driving side of the switch and its interaction with the load on the driven side.
3. Minimums guaranteed but not tested.
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INDUSTRIAL TEMPERATURE RANGE
IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
TIMING WAVEFORMS - SYNCHRONOUS MODE, DEMUX FUNCTION
SY NC
CLK EN
CLK
SE L
O E
Port Y
Port A
Port B
HO LD PR EVIO US DAT A, DATA 1
HO LD PR EVIO US DAT A, DATA 2
DAT A 1
DAT A 2
IN V ALID D ATA
DAT A
1
DAT A 0
IN V ALID D ATA
t
SEC
t
H EC
t
SC S
t
H CS
t
SC S
t
H CS
t
PLH ,
t
PH L
t
C SO
t
PLH ,
t
PH L
t
C SO
DAT A 1
DAT A 2
DAT A 0
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IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
INDUSTRIAL TEMPERATURE RANGE
TIMING WAVEFORMS - SYNCHRONOUS MODE, MUX FUNCTION
SY NC
CLKEN
CLK
SEL0, SE L1
Port A
Port D
Port Y
D AT A1
DAT A2
INVALID D ATA
DATA3
DAT A4
t
SE C
t
H EC
t
SC S
t
H CS
t
SC S
t
H CS
DAT A1
DAT A2
INV ALID D ATA
DAT A3
DAT A4
t
C SO
t
PLH ,
t
PH L
t
C SO
t
PLH ,
t
PH L
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INDUSTRIAL TEMPERATURE RANGE
IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
TIMING WAVEFORMS - ASYNCHRONOUS MODE, MUX FUNCTION
SY NC
SEL
O E
Port A
Port B
Port Y
INV ALID
DATA
DATA1
DATA2
INV ALID D ATA
DATA3
INV ALID D ATA
DATA1
DATA2
DATA3
DATA3
t
PLH ,
t
PH L
t
PLH ,
t
PH L
t
AS O
t
PLZ,
t
PH Z
t
PZL,
t
PZH
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IDTQS34XS257
HIGH-SPEED CMOS SYNCHROSWITCH 32:16 MUX/DEMUX
INDUSTRIAL TEMPERATURE RANGE
IDTQ S
XXXXX
XX
Package
Device Type
Blank
Industrial (-40C to +85C)
150 m il M illipaQ
Q 3
34XS257
High Speed CM O S SynchroSwitch 32:16 M ux/Dem ux
X
Process
ORDERING INFORMATION
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for SALES:
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Santa Clara, CA 95054
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www.idt.com*
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The IDT logo, QuickSwitch, and SynchroSwitch are registered trademarks of Integrated Device Technology, Inc.
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