1
PS8485D 09/22/04
Features
Dual 2x2 Crosspoint/Repeater Switch
Meets or Exceeds the Requirements of
ANSI TIA/EIA-644-1995
Designed for Signaling Rates up to 650 Mbit/s (325Mhz)
Operates from a single 3.3V Supply: 40C to 85C
Low-Voltage Differential Signaling with Output Voltages of
350mV into:
- 100 load (PI90LV044)
- 50 load Bus LVDS Signaling (PI90LVB044)
Accepts 350mV differential inputs
Wide common mode input range: 0.2V to 2.7V
Output drivers are high impedance when disabled or
when V
CC
1.5V
Inputs are open, short, and terminated fail safe
Propagation Delay Time: 3.5ns
ESD protection is 10kV on bus pins
Bus Pins are High Impedance when disabled or
with V
CC
less than 1.5V
TTL Inputs are 5V Tolerant
Power Dissipation at 400 Mbit/s of 250mW
Packaging (Pb-free & Green available):
- 28-pin QSOP (Q)
- 28-pin TSSOP (L)
Description
The PI90LV044 and PI90LVB044 are monolithic dual 2x2 asyn-
chronous crosspoint/repeater switches. The crosspoint function
is based on a multiplexer tree architecture. Each 2x2 switch can
be considered as a pair of 2:1 multiplexers that share the same
inputs. The signal path through each switch is fully differential
with minimal propagation delay. The signal path is unregistered,
so no clock is required for the data inputs. The signal line drivers
and receivers use Low Voltage Differential Signaling (LVDS) to
achieve signaling rates as high as 650Mbps.
The LVDS standard provides a minimum differential output volt-
age magnitude of 247 mV into a 100 load and receipt of 100
mV signals with up to 1V of ground potential difference between a
transmitter and receiver. The PI90LVB044 doubles the output drive
current to achieve LVDS levels with a 50 ohm load.
The intended application of these devices is for loop-through and
redundant channel switching for both point-to-point baseband
(PI90LV044) and multipoint (PI90LVB044) data transmissions
over controlled impedance media.
Block Diagram
Pin Configuration
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
V
CC
1Y
1Z
2DE
2Z
2Y
GND
V
CC
3Y
3Z
4DE
4Y
4Z
GND
1B
1A
S0
1DE
S1
2A
2B
3A
3B
S2
3DE
S3
4A
4B
28
27
26
25
24
23
22
21
20
19
18
17
16
15
1
2
3
4
5
6
7
8
9
10
11
12
13
14
1DE/2DE
1Y/1Z
2Y/2Z
3DE/4DE
3Y/3Z
4Y/4Z
S0,S1
1A/1B
2A/2B
S2/S3
3A/3B
4A/4B
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
2
PS8485D 09/22/04
Figure 1. Possible Signal Routing
MUX Truth Table
Input
Output
Function
S3, S1
S2, S0
1Y/1Z - 3Y/3Z
2T/2Z - 4Y/4Z
0
0
1A/1B - 3A/3B
1A/1B - 3A/3B
Splitter
0
1
2A/2B - 4A/4B
2A/2B - 4A/4B
Splitter
1
0
1A/1B - 3A/3B
1A/1B - 3A/3B
Router
1
1
2A/2B - 4A/4B
2A/2B - 4A/4B
Router
Note:
1. Setting nDE to 0 will set Ouput nY/nZ to High Impedance.
S1/S0
1A/1B
2A/2B
S3/S2
3A/3B
4A/4B
1DE/2DE
1Y/1Z
2Y/2Z
3DE/4DE
3Y/3Z
4Y/4Z
Cross Point
Router
Pass Through
Router
S1/S0
1A/1B
2A/2B
S3/S2
3A/3B
4A/4B
1DE/2DE
1Y/1Z
2Y/2Z
3DE/4DE
3Y/3Z
4Y/4Z
Splitter A
Splitter B
Splitter Options
Router Options
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
3
PS8485D 09/22/04
Supply Voltage Range, V
CC
(1).......................................................................
0.5V to 4V
Voltage Range (DE, S0, S1)...............................................................0.5 to 6V
Input Voltage Range, V
I
(A or B)..................................... 0.5V to V
CC
+ 0.5V
Electrostatic Discharge: A, B, Y, Z, and GND
(2).........
Class 3, A: 16kV, B:600V
All Pins..................................................... Class 3, A: 7kV, B:500V
Storage Temperature Range ......................................................65C to 150C
Lead Temperature 1, 6 mm (1/16 inch) from case for 10 seconds........... 260C
Absolute Maximum Ratings Over Operating Free-Air Temperature
(1)
Notes:
1. Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "Recommended Operating Conditions" is not
implied. Exposure to Absolute-Maximum-Rated conditions for extended periods may affect device reliability.
2. All voltage values, except differential I/O bus voltages, are with respect to ground terminal.
3. Tested in accordance with MIL-STD-883C Method 3015.7
Recommended Operating Conditions
Min.
Nom.
Max.
Units
Supply Voltage, V
CC
3.0
3.3
3.6
V
High-Level input voltage, V
IH
S1 - S3, 1DE - 4DE
2
Low-Level input voltage, V
IL
0.8
Magnitude of Differential Input Voltage | V
ID
|
0.1
0.6
Common Mode input voltage, V
IC
(see figure 2)
| V
ID
|
2
2.4 - | V
ID
|
2
V
CC
- 0.8
Operating free-air Temperature, T
A
-40
85
C
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
4
PS8485D 09/22/04
Receiver Electrical Characteristics Over Recommended Operating Conditions
(unless otherwise noted)
Symbol
Parameter
Test Conditions
Min.
Typ.
(1)
Max.
Units
V
ITH+
Positive going differential input voltage threshold
VCM = 1.2V
100
mV
V
ITH-
Negative going differential input voltage threshold
-100
I
I
Input current (A or B inputs)
VI = 0V
-2
-20
A
VI = 2.4V
-1.2
I
I (OFF)
Power-off input current (A or B inputs)
VCC = 0V
20
Figure 2. Common-Mode Input Voltage vs. Differential Voltage
2.5
2
1.5
1
0.5
0
0.1
0.2
0.3
0.4
0.5
0.6
MAX at V
CC
> 3.15V
MAX at V
CC
= 3V
MIN
VID Differential Input Voltage V
V
IC
Common-Mode Input
V
o
l
t
a
g
e
V
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
5
PS8485D 09/22/04
Receiver/Driver Electrical Characteristics Over Recommended Operating Conditions
(unless otherwise noted)
Symbol
Parameter
Test Condition
Min.
Typ.
(1)
Max.
Units
V
OD
Differential Output voltage magnitude
R
L
= 100 (LV)
R
L
= 50 (LVB)
247
440
590
mV
V
OD
Change in differential Output voltage magnitude
between logic states
-50
50
V
OC(SS)
Steady-state common-mode output voltage
1.062
1.375
V
V
OC(SS)
Change in steady-state common-mode output
voltage between logic states
-50
3
50
mV
V
OC(PP)
Peak-to-peak common-mode output voltage
150
I
CC
Supply Current
No load
16
24
mA
R
L
= 100 (LV)
26
40
R
L
= 50 (LVB)
42
54
All Channels Disabled
6
12
I
IH
High level input current
DE
V
IH
= 5
40
nA
S1, S2, S3, S4
-3
A
I
IL
Low level input current
DE
V
IL
= 0.8V
-20
nA
S1, S2, S3, S4
10
A
I
OS
Short circuit output current
V
OY
or V
OZ
= 0V,
V
OD
= 0V
-10
mA
I
OZ
High impedence output current
V
OD
= 600mV
1.5
25
nA
V
O
- 0V or V
CC
1.5
25
I
O(OFF)
Power off output current
V
CC
= 0V, V
O
= 3.6V
1.5
40
C
IN
Input Capacitance
S0 - S3, 1DE - 4DE
3
pF
8
Note:
1. All typical values are at 25C and with a 3.3 supply
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
6
PS8485D 09/22/04
Differential Receiver to Driver Switching Characteristics Over Recommended Operating Conditions
(unless otherwise noted)
Symbol
Parameter
Test Condition
Min. Typ.
(1)
Max. Units
t
PLH
Differential propagation delay, low-to-high
C
L
= 10pF
4.0
6.0
ns
t
PHL
Differential propagation delay, high-to-low
4.0
6.0
t
sk(p)
Pulse skew ( | t
PHL
= t
PLH
| )
0.25
0.3
t
r
Transition, low-to-high
LV044
1.0
1.5
LVB044
0.8
1.3
t
f
Transition, high-to-low
LV044
1.0
1.5
LVB044
0.8
1.3
t
PHZ
Propagation delay time, high-level-to-high-impedence output
4.0
10
t
PLZ
Propagation delay time, low-level-to-high-impedance output
4.3
10
t
PZH
Propagation delay time, high-impedence to high-level output
3.0
10
t
PZL
Propagation delay time, high-impdeence tolow-level output
2.0
10
t
PHL
_R1_Dx
Channel-tochannel skew, receiver to driver
(2)
-
95
ps
t
PLH
_R1_Dx
-
95
t
PHL
_R2_Dx
-
95
t
PLH
_R2_Dx
-
95
Notes:
1. All typical values are at 25C and with a 3.3 supply
2. These parametric values are measured over supply voltage and temperature ranges recommended for the device
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
7
PS8485D 09/22/04
Parameter Measurement Information
Figure 3. Test Circuit and Voltage Definitions for the Differential Output Signal
Figure 4. Test Circuit and Definitions for the Driver Common-Mode Output Voltage
Y
Z
VOD
Input
(see Note A)
CL = 10 pF
(2 Places)
(see Note C)
RL (see Note B)
100%
80%
20%
0%
VOD
0
tf
tr
VI(B)
VI(A)
1.4 V
1 V
A
Pulse
Generator
B
R
D
DE
Notes: A. All input pulses are supplied by a generator having the following characteristics: tr or tf 1ns, pulse repetition rate (PRR) - 50 Mpps,
pulse width = 10 0.2ns.
B. R
L
= 100
or 50 1%.
C. C
L
includes instrumentation and fixture capacitance within 6mm of the D.U.T.
D. The measurement of V
OC(PP)
is made on test equipment with a 3dB bandwidth of at least 300 MHz.
Y
Z
Input
(see Note A)
CL = 10 pF
(2 Places)
(see Note C)
VOC
A
VCC
VOC(PP)
(see Note D)
VOC(SS)
VI(B)
VI(A)
Pulse
Generator
DE
B
R
D
1.4 V
1 V
RL (see Note B)
(2 Places)
Notes: A. All input pulses are supplied by a generator having the following characteristics: tr or tf 1ns, pulse repetition rate (PRR) - 50 Mpps,
pulse width = 10 0.2ns.
B. R
L
= 100
or 50 1%.
C. C
L
includes instrumentation and fixture capacitance within 6mm of the D.U.T.
D. The measurement of V
OC(PP)
is made on test equipment with a 3dB bandwidth of at least 300 MHz.
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
8
PS8485D 09/22/04
Figure 5. Differential Receiver to Driver Propagation Delay and Driver Transition Time Waveforms
R
D
10 pF
Pulse
Generator
80%
20%
0-V Differential
VOY VOZ
VIB
VIA
1.4 V
1 V
tPLH
tPHL
tr
tf
A
B
10 pF
VOZ
VOY
1.4 V
1 V
0-V Differential
0-V Differential
1.2-V CM
1.2-V CM
DE
RL (see Note A)
Y
Z
Notes: A. R
L
= 100
or 50 1%
B. All input pulses are supplies by a generator having the following characteristics:
pulse repetition rate (PPR) = 50 Mpps, pulse width = 10 0.2ns.
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
9
PS8485D 09/22/04
Figure 6. Enable and Disable Timing Circuit
A
B
R
D
Y
Z
DE
1.2 V
RL/2
(see Note A)
RL/2
(see Note A)
2 V
1.4 V
0.8 V
1.2 V
1.15 V
1 V
1.4 V
1.25 V
1.2 V
tPZH
tPHZ
tPZL
tPLZ
DE
1.2 V
1 V or 1.4 V
VOY or VOZ
VOY or VOZ
Notes:
A. RL = 100 or 50 1%
B. All input pulses are supplied by a generator having the following characteristics: pulse repetition rate (PRR) = 0.5 Mpps,
pulse width = 500
10ns.
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
10
PS8485D 09/22/04
IOH High-Level Output Current mA
PI90LV044
PI90LVB044
PI90LVB044
PI90LV044
HIGH-LEVEL OUTPUT VOLTAGE
vs
HIGH-LEVEL OUTPUT CURRENT
1
.5
0
2
1
3
4
1.5
VCC = 3.3 V
TA = 25C
2
2.5
0
3
V
OH
High-Le
vel Ouptut V
o
l
t
a
g
e
V
3.5
IOL Low-Level Output Current mA
LOW-LEVEL OUTPUT VOLTAGE
vs
LOW-LEVEL OUTPUT CURRENT
1
0
4
0
2
VCC = 3.3 V
TA = 25C
3
6
2
V
OL
Lo
w-Le
vel
Output V
o
l
t
a
g
e
V
4
IOH High-Level Output Current mA
HIGH-LEVEL OUTPUT VOLTAGE
vs
HIGH-LEVEL OUTPUT CURRENT
1
.5
0
4
2
3
8
1.5
VCC = 3.3 V
TA = 25C
2
2.5
0
6
V
OH
High-Le
vel Output V
o
l
t
a
g
e
V
3.5
IOL Low-Level Output Current mA
LOW-LEVEL OUTPUT VOLTAGE
vs
LOW-LEVEL OUTPUT CURRENT
1
0
8
0
2
VCC = 3.3 V
TA = 25C
3
12
4
V
OL
Lo
w-Le
vel
Output V
o
l
t
a
g
e
V
4
6
10
2
Typical Characteristics
Figure 7
Figure 8
Figure 9
Figure 10
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
11
PS8485D 09/22/04
.386
.394
.053
.069
.004
.010
SEATING
PLANE
.025
BSC
.007
.010
.228
.244
0.150
0.157
1
28
.016
.050
X.XX
X.XX
DENOTES DIMENSIONS
IN MILLIMETERS
0.635
9.804
10.009
1.35
1.75
5.79
6.19
0.41
1.27
0.101
0.254
.008
.012
0.203
0.305
3.81
3.99
0.178
0.254
.033
0.84
.015 x 45
REF
Detail A
Detail A
.008
0.20
MIN.
Guage Plane
.010
0.254
.041
1.04
REF
.016
.035
0.41
0.89
0-6
.008
.013
0.20
0.33
.378
.386
.047
1.20
.002
.006
SEATING
PLANE
.0256
BSC
.018
.030
.252
BSC
1
28
.169
.177
X.XX
X.XX
DENOTES CONTROLLING
DIMENSIONS IN MILLIMETERS
0.05
0.15
6.4
0.45
0.75
0.09
0.20
4.3
4.5
9.6
9.8
0.65
0.19
0.30
.007
.012
.004
.008
Max
Packaging Mechanical: 28-Pin QSOP (Q)
Packaging Mechanical: 28-Pin TSSOP (L)
PI90LV044, PI90LVB044
LVDS Dual 2x2 Crosspoint/Repeater Switch
12
PS8485D 09/22/04
Ordering Information
Ordering Code
Package Code
Package Type
PI90LV044Q
Q
28-Pin 150-mil QSOP
PI90LV044QE
Q
Pb-free & Green, 28-Pin 150-mil QSOP
PI90LV044L
L
28-pin 170-mil TSSOP
PI90LV044LE
L
Pb-free & Green, 28-pin 170-mil TSSOP
PI90LVB044Q
Q
28-Pin 150-mil QSOP
PI90LVB044QE
Q
Pb-free & Green, 28-Pin 150-mil QSOP
PI90LVB044L
L
28-pin 170-mil TSSOP
PI90LVB044LE
L
Pb-free & Green, 28-pin 170-mil TSSOP
Notes:
1. Thermal characteristics can be found on the company web site at www.pericom.com/packaging/
2. Number of Transistors = TBD
Pericom Semiconductor Corporation 1-800-435-2336 www.pericom.com
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