MAXIM MAX4890EETJ

19-0624; Rev 0; 8/06
1000 Base-T, ±15kV ESD Protection LAN Switches
The MAX4890E/MAX4892E meet the needs of high-speed
differential switching. The devices handle the needs of
Gigabit Ethernet (10/100/1000) Base-T switching as
well as LVDS and LVPECL switching. The MAX4890E/
MAX4892E provide enhanced ESD protection up to
±15kV, and excellent high-frequency response, making
the devices especially useful for interfaces that must go to
an outside connection.
Both devices provide extremely low capacitance
(CON), as well as low resistance (RON), for low-insertion
loss and very wide bandwidth. In addition to the four
pairs of DPDT switches, the MAX4892E provides LED
switching for laptop computer/docking station use.
The MAX4890E/MAX4892E are pin-for-pin equivalents
to the MAX4890/MAX4892 and can replace these
devices for those applications requiring the enhanced
ESD protection. Both devices are available in spacesaving TQFN packages and operate over the standard
-40°C to +85°C temperature range.
Applications
Notebooks and Docking Stations
Servers and Routers with Ethernet Interfaces
Board-Level Redundancy Protection
SONET/SDH Signal Routing
T3/E3 Redundancy Protection
LVDS and LVPECL Switching
1B2
20
SEL
2B1
3B1
2B2
3B2
4B1
5B1
4B2
19
5B2
1
27
2
26
A3
LED0
0LED1
0LED2
3
25
4
24
A4
A5
A6
7
23
MAX4892E
6
22
21
8
*EP
16
17
18
7B1
6B1
15
14
11
13
10
A7
GND
LED1
1LED1
1LED2
7B2
6B2
9
12
♦ Ultra-Low On-Capacitance (CON): 8pF (typ)
♦ -23dB Return Loss (100MHz)
♦ -3dB Bandwidth: 650MHz
♦ Optimized Pin Out for Easy Transformer and PHY
Interface
♦ Built-In LED Switches for Switching Indicators to
Docking Station (MAX4892E)
♦ Low 450µA (max) Quiescent Current
♦ Bidirectional 8 to 16 Multiplexer/Demultiplexer
♦ Standard Pin Out, Matching the MAX4890 and
MAX4892
♦ Space-Saving Lead-Free Packages
32-Pin, 5mm x 5mm, TQFN Package
36-Pin, 6mm x 6mm, TQFN Package
Ordering Information
PART
PINPACKAGE
LED
SWITCHES
PKG
CODE
MAX4890EETJ+
32 TQFN-EP*
—
T-3255-4
MAX4892EETX+
36 TQFN-EP*
3
T-3666-3
+Denotes lead-free package.
Note: All devices are specified over the -40°C to +85°C operating
temperature range.
*EP = Exposed pad.
Eye Diagram
A1
A2
5
♦ ±15kV ESD Protected Per MIL-STD-883, Method
3015
♦ Single +3.0V to +3.6V Power-Supply Voltage
♦ Low On-Resistance (RON): 4Ω (typ), 6.5Ω (max)
28
29
0B1
1B1
0B2
30
31
32
33
34
A0
36
+
35
TOP VIEW
V+
LED2
2LED1
2LED2
Pin Configurations
Features
CH2: 4B2, 100mV/div
CH1: 5B2, 100mV/div
f = 125MHz
TQFN
*EXPOSED PAD CONNECTED TO GND.
Pin Configurations continued at end of data sheet.
Typical Operating Circuit and Functional Diagrams appear
at end of data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX4890E/MAX4892E
General Description
MAX4890E/MAX4892E
1000 Base-T, ±15kV ESD Protection LAN Switches
ABSOLUTE MAXIMUM RATINGS
V+ ……………………………………………………… -0.3V to +4V
All Other Pins………………………………….. -0.3V to (V+ + 0.3V)
Continuous Current (A_ to _B_) ......................................±120mA
Continuous Current (LED_ to _LED_) .…………………… ±40mA
Peak Current (A_ to _B_)
(pulsed at 1ms, 10% duty cycle) ……………………. ±240mA
Current into Any Other Pin................................................±20mA
Continuous Power Dissipation (TA = +70°C)
32-Pin TQFN (derate 34.5mW/°C above +70°C) …….. 2.76W
36-Pin TQFN (derate 35.7mW/°C above +70°C) …….. 2.85W
ESD Protection, Human Body Model .............................±15kV
Operating Temperature Range …………………. -40°C to +85°C
Junction Temperature.……………………………………. +150°C
Storage Temperature Range .…………………. -65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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 in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V+ = +3V to +3.6V, TA = TJ = TMIN to TMAX, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
4
5.5
UNITS
ANALOG SWITCH
On-Resistance
On-Resistance LED Switches
On-Resistance Match
Between Channels
On-Resistance Flatness
Off-Leakage Current
RON
RONLED
∆RON
RFLAT(ON)
V+ = 3V,
IA_ = -40mA,
VA_ = 0, 1.5V, 3V
TA = +25°C
Ω
TMIN to TMAX
6.5
V+ = 3V, I_LED_ = -40mA, VLED_ = 0, 1.5V, 3V
(MAX4892E)
V+ = 3V,
IA_= -40mA,
VA_ = 0, 1.5V, 3V
(Note 2)
40
TA = +25°C
0.5
Ω
1.5
Ω
TMIN to TMAX
2
V+ = 3V, IA_ = -40mA, VA_ = 1.5V, 3V
ILA_(OFF)
V+ = 3.6V, VA_ = 0.3V, 3.3V;
V_B1 or V_B2 = 3.3V, 0.3V
ILA_(ON)
V+ = 3.6V, VA_= 0.3V, 3.3V;
V_B1 or V_B2 = 0.3V, 3.3V or floating
Ω
0.01
-1
+1
µA
On-Leakage Current
-1
+1
ESD PROTECTION
ESD Protection
Human Body Model (spec MIL-STD-883,
Method 3015)
±15
kV
SWITCH AC PERFORMANCE
Insertion Loss
ILOS
RS = RL = 50Ω, unbalanced, f = 1MHz,
(Note 2)
0.6
dB
Return Loss
RLOS
f = 100MHz
-23
dB
2
_______________________________________________________________________________________
1000 Base-T ±15kV ESD Protection LAN Switch
MAX4890E/MAX4892E
ELECTRICAL CHARACTERISTICS (continued)
(V+ = +3V to +3.6V, TA = TJ = TMIN to TMAX, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
VCT1
Crosstalk
VCT2
CONDITIONS
Any switch to any
switch; RS = RL =
50Ω, unbalanced,
Figure 1
MIN
TYP
f = 25MHz
-50
f = 125MHz
-26
MAX
UNITS
dB
SWITCH AC CHARACTERISTIC
-3dB Bandwidth
BW
Off-Capacitance
On-Capacitance
Turn-On Time
Turn-Off Time
Propagation Delay
Output Skew Between Ports
RS = RL = 50Ω, unbalanced
650
MHz
COFF
f = 1MHz, _B_, A_
3.5
pF
CON
f = 1MHz, _B_, A_
6.5
tON
VA_ = 1V, RL, 100Ω, Figure 2
tOFF
VA_ = 1V, RL, 100Ω, Figure 2
pF
50
50
ns
ns
tPLH, tPHL
RS = RL = 50Ω, unbalanced, Figure 3
0.1
ns
tSK(o)
Skew between any two ports, Figure 4
0.01
ns
SWITCH LOGIC
Input-Voltage Low
VIL
V+ = 3.0V
Input-Voltage High
VIH
V+ = 3.6V
Input-Logic Hysteresis
VHYST
V+ = 3.3V
Input Leakage Current
ISEL
Operating Supply-Voltage Range
V+
Quiescent Supply Current
I+
V+ = 3.6V, VSEL = 0 or V+
V+ = 3.6V, VSEL = 0 or V+
0.8
2.0
100
V
mV
-5
+5
µA
3.0
3.6
V
450
µA
280
Note 1: Specifications at -40°C are guaranteed by design.
Note 2: Guaranteed by design.
_______________________________________________________________________________________
3
Typical Operating Characteristics
(V+ = 3.3V, TA = +25°C, unless otherwise noted.)
LED_ON-RESISTANCE vs. VLED_
5
22
TA = +85°C
20
LEAKAGE CURRENT vs. TEMPERATURE
40
MAX4890E toc02
MAX4890E toc01
24
36
32
RONLED (Ω)
TA = +85°C
3
TA = -40°C
14
12
2
10
8
1
6
4
TA = +25°C
LEAKAGE CURRENT (pA)
18
16
4
TA = +25°C
TA = -40°C
0.5
1.0
1.5
2.0
2.5
3.0
0.5
1.0
1.5
2.0
2.5
16
12
ILA_(OFF)
-40
3.0
35
300
280
260
240
MAX4890E toc05
0
-1
INSERTION LOSS (dB)
320
10
TEMPERATURE (°C)
SINGLE-ENDED INSERTION LOSS
vs. FREQUENCY
MAX4890E toc04
V+ = 3.6V
340
ILA_(ON)
-15
VLED_ (V)
QUIESCENT SUPPLY CURRENT
vs. TEMPERATURE
QUIESCENT SUPPLY CURRENT (µA)
20
0
0
VA_ (V)
-2
-3
-4
-5
-6
220
-7
200
-8
-40
-15
10
35
TEMPERATURE (°C)
4
24
4
0
0
28
8
2
0
MAX4890E toc03
ON-RESISTANCE vs. VA_
6
RON (Ω)
MAX4890E/MAX4892E
1000 Base-T, ±15kV ESD Protection LAN Switches
60
85
1
10
100
1000
FREQUENCY (MHz)
_______________________________________________________________________________________
60
85
1000 Base-T ±15kV ESD Protection LAN Switch
PIN
NAME
FUNCTION
MAX4892E
MAX4890E
1
32
A1
Differential PHY Interface Pair. Connect to the Ethernet PHY.
2
1
A2
Differential PHY Interface Pair. Connect to the Ethernet PHY.
3
2
A3
Differential PHY Interface Pair. Connect to the Ethernet PHY.
4
—
LED0
LED0 Input
5
—
0LED1
0LED1 Output. Drive SEL low (SEL = 0) to connect LED0 to 0LED1.
6
—
0LED2
7
7
A4
Differential PHY Interface Pair. Connect to the Ethernet PHY.
8
8
A5
Differential PHY Interface Pair. Connect to the Ethernet PHY.
9
9
A6
Differential PHY Interface Pair. Connect to the Ethernet PHY.
10
10
A7
Differential PHY Interface Pair. Connect to the Ethernet PHY.
11
11
GND
Ground
12
—
LED1
LED1 Input
13
—
1LED1
1LED1 Output. Drive SEL low (SEL = 0) to connect LED1 to 1LED1.
14
—
1LED2
15
13
7B2
B2 Differential Pair
16
14
6B2
B2 Differential Pair
17
15
7B1
B1 Differential Pair
18
16
6B1
B1 Differential Pair
19
17
5B2
B2 Differential Pair
20
18
4B2
B2 Differential Pair
21
19
5B1
B1 Differential Pair
22
20
4B1
B1 Differential Pair
23
21
3B2
B2 Differential Pair
24
22
2B2
B2 Differential Pair
25
23
3B1
B1 Differential Pair
26
24
2B1
B1 Differential Pair
27
29
SEL
Select Input. SEL selects switch connection. See the Truth Table (Table1).
28
25
1B2
B2 Differential Pair
29
26
0B2
B2 Differential Pair
30
27
1B1
B1 Differential Pair
31
28
0B1
B1 Differential Pair
32
—
2LED2
2LED2 Output. Drive SEL high (SEL = 1) to connect LED2 to 2LED2.
33
—
2LED1
2LED1 Output. Drive SEL low (SEL = 0) to connect LED2 to 2LED1.
34
—
LED2
35
30
V+
Positive-Supply Voltage Input. Bypass to GND with a 0.1µF ceramic capacitor.
36
31
A0
Differential PHY Interface Pair. Connect to the Ethernet PHY.
—
3-6, 12
N.C.
—
—
EP
0LED2 Output. Drive SEL high (SEL = 1) to connect LED0 to 0LED2.
1LED2 Output. Drive SEL high (SEL = 1) to connect LED1 to 1LED2.
LED2 Input
No Connection. Not internally connected.
Exposed Pad. Connect exposed pad to GND or leave it unconnected.
_______________________________________________________________________________________
5
MAX4890E/MAX4892E
Pin Description
MAX4890E/MAX4892E
1000 Base-T, ±15kV ESD Protection LAN Switches
MAX4892E
SINGLE-ENDED BANDWIDTH
NETWORK
ANALYZER
50Ω TRACE
SINGLE-ENDED CROSSTALK
NETWORK
ANALYZER
NETWORK
ANALYZER
50Ω TRACE
A2
2
50Ω TRACE
NETWORK
ANALYZER
2B1
26
R13
49.9Ω
50Ω TRACE
A3
3
3B1
25
R14
49.9Ω
SINGLE-ENDED OFF-ISOLATION
NETWORK
ANALYZER
36 TQFN
0B1
31
A0
36
50Ω TRACE
A4
7
4B1
22
50Ω TRACE
NETWORK
ANALYZER
R15
49.9Ω
Figure 1. Single-Ended Bandwidth, Crosstalk, and Off-Isolation
Detailed Description
The MAX4890E/MAX4892E are high-speed analog
switches targeted for 1000 Base-T applications. In a
typical application, the MAX4890E/MAX4892E switch
the signals from two separate interface transformers
and connect the signals to a single 1000 Base-T
Ethernet PHY (see the Typical Operating Circuit). This
configuration simplifies docking station design by
avoiding signal reflections associated with unterminated transmission lines in a T configuration. The
MAX4890E/MAX4892E are protected against ±15kV
electrostatic discharge (ESD) shocks. The MAX4892E
also includes LED switches that allow the LED output
signals to be routed to a docking station along with the
Ethernet signals. See the Functional Diagrams.
With their low resistance and capacitance, as well as
high ESD protection, the MAX4890E/MAX4892E can be
used to switch most low-voltage differential signals,
6
such as LVDS, SEREDES, and LVPECL, as long as the
signals do not exceed maximum ratings of the devices.
The MAX4890E/MAX4892E switches provide an
extremely low capacitance and on-resistance to meet
Ethernet insertion and return-loss specifications. The
MAX4892E features three built-in LED switches.
The MAX4890E/MAX4892E incorporate a unique architecture design utilizing only n-channel switches within
the main Ethernet switch, reducing I/O capacitance and
channel resistance. An internal two-stage charge pump
with a nominal output of 7.5V provides the high voltage
needed to drive the gates of the n-channel switches
while maintaining a consistently low RON throughout the
input signal range. An internal bandgap reference set to
1.23V and an internal oscillator running at 2.5MHz provide proper charge-pump operation. Unlike other
charge-pump circuits, the MAX4890E/MAX4892E
include internal flyback capacitors, reducing design
time, board space, and cost.
_______________________________________________________________________________________
1000 Base-T, ±15kV ESD Protection LAN Switches
SEL
CONNECTION
0
A_ to _B1, LED_ to _LED1
1
A_ to _B2, LED_ to _LED2
Digital Control Inputs
The MAX4890E/MAX4892E provide a single digital control SEL. SEL controls the switches as well as the LED
switches as shown in Table 1.
Analog Signal Levels
The on-resistance of the MAX4890E/MAX4892E is very
low and stable as the analog input signals are swept
from ground to V+ (see the Typical Operating
Characteristics). The switches are bidirectional, allowing A_ and _B_ to be configured as either inputs or outputs.
ESD Protection
The MAX4890E/MAX4892E are characterized using the
Human Body Model for ±15kV of ESD protection. Figure 5
shows the Human Body Model. This model consists of a
100pF capacitor charged to the ESD voltage of interest
which is then discharged into the test device through a
1.5kΩ resistor. All signal and control pins are ESD protected to ±15kV HBM (Human Body Model).
Typical Operating Circuit
The Typical Operating Circuit shows the MAX4890E/
MAX4892E in a 1000 Base-T docking station application.
Power-Supply Sequencing and
Overvoltage Protection
Caution: Do not exceed the absolute maximum ratings.
Stresses beyond the listed ratings may cause permanent damage to the device.
Proper power-supply sequencing is recommended for
all CMOS devices. Always apply V+ before applying
analog signals, especially if the analog signal is not
current limited.
Layout
High-speed switches require proper layout and design
procedures for optimum performance. Keep design-controlled-impedance pc board traces as short as possible.
Ensure that bypass capacitors are as close as possible
to the device. Use large ground planes where possible.
Chip Information
PROCESS: BiCMOS
_______________________________________________________________________________________
7
MAX4890E/MAX4892E
Applications Information
Table 1. Truth Table
MAX4890E/MAX4892E
1000 Base-T, ±15kV ESD Protection LAN Switches
SEL
VIH
3.0V
50%
50%
2.0V
VIL
A_
1.0V
_B1
tON
50%
tPHL
tPLH
50%
tOFF
VH
0V
2.0V
tON
tOFF
_B2
50%
_B_
VL
50%
PULSE SKEW = tSK(p) = |tPHL - tPLH|
THE MAX4890E/MAX4892E SWITCHES ARE FULLY BIDIRECTIONAL.
0V
Figure 2. Turn-On and Turn-Off Times
Figure 3. Propagation Delay Times
3.0V
2.0V
A_
1.0V
tPLHX
RC
1MΩ
tPHLX
CHARGE-CURRENT
LIMIT RESISTOR
VOH
2.0V
_B_
tPLHY
HIGHVOLTAGE
DC
SOURCE
VOL
Cs
100pF
RD
1500Ω
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
tPHLY
VOH
2.0V
_B_
VOL
OUTPUT SKEW = tSK(O) = |tPLHY - tPLHX| OR |tPHLY - tPHLX|
THE MAX4890E/MAX4892E SWITCHES ARE FULLY BIDIRECTIONAL.
Figure 4. Output Skew
8
Figure 5. Human Body ESD Test Model (MIL-STD-883, Method 3015)
_______________________________________________________________________________________
1000 Base-T, ±15kV ESD Protection LAN Switches
DOCKING STATION
TRANSFORMER
RJ-45
LED
CONNECTOR
NOTEBOOK
0B2
1B2
2B2
3B2
TRD0_P
TRD0_N
A0
A1
TRD1_P
TRD1_N
A2
A3
TRD2_P
TRD2_N
A4
A5
TRD3_P
TRD3_N
A6
A7
ETHERNET
PHY/MAC
6B2
7B2
_LED2
MAX4892E
0B1
1B1
2B1
3B1
4B1
5B1
RJ-45
6B1
7B1
LED_
SEL
SEL_DOCK
TRANSFORMER
LED_OUT
4B2
5B2
_LED1
LED
_______________________________________________________________________________________
9
MAX4890E/MAX4892E
Typical Operating Circuit
1000 Base-T, ±15kV ESD Protection LAN Switches
MAX4890E/MAX4892E
Functional Diagrams
A0
A1
0B1
1B1
A0
A1
0B1
1B1
0B2
0B2
1B2
1B2
A2
2B1
A2
2B1
A3
3B1
A3
3B1
2B2
2B2
3B2
3B2
A4
4B1
A4
4B1
A5
5B1
A5
5B1
4B2
4B2
5B2
5B2
A6
6B1
A6
6B1
A7
7B1
A7
7B1
6B2
6B2
7B2
7B2
LED0
0LED1
0LED2
LED1
1LED1
1LED2
LED2
2LED1
2LED2
SEL
MAX4890E
SEL
MAX4892E
10
______________________________________________________________________________________
1000 Base-T, ±15kV ESD Protection LAN Switches
MAX4890E/MAX4892E
Pin Configurations (continued)
A0
V+
SEL
0B1
1B1
0B2
1B2
+
A1
TOP VIEW
32
31
30
29
28
27
26
25
A2
1
24
2B1
A3
2
23
3B1
N.C.
3
22
2B2
N.C.
4
21
3B2
20
4B1
19
5B1
18
4B2
17
5B2
9
10
11
12
13
14
15
16
6B1
8
7B1
A5
*EP
6B2
7
7B2
A4
N.C.
6
GND
N.C.
A7
5
A6
N.C.
MAX4890E
TQFN
*EXPOSED PADDLE CONNECTED TO GND.
______________________________________________________________________________________
11
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
QFN THIN.EPS
MAX4890E/MAX4892E
1000 Base-T, ±15kV ESD Protection LAN Switches
12
______________________________________________________________________________________
1000 Base-T, ±15kV ESD Protection LAN Switches
QFN THIN.EPS
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 13
© 2006 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
MAX4890E/MAX4892E
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)