MAXIM MAX4891ETJ

19-3577; Rev 1; 8/05
10/100/1000 Base-T Ethernet LAN Switch
The MAX4890/MAX4891/MAX4892 high-speed analog
switches meet the needs of 10/100/1000 Base-T applications. These devices switch the signals from two
interface transformers and connect the signals to a single 10/100/1000 Base-T Ethernet PHY, simplifying
docking station design and reducing manufacturing
costs. The MAX4890/MAX4891/MAX4892 can also
route signals from a common interface transformer to
two different boards in board-redundancy applications.
The MAX4890/MAX4891/MAX4892 switches provide an
extremely low capacitance and on-resistance to meet
Ethernet insertion and return-loss specifications. The
MAX4891/MAX4892 feature one and three built-in LED
switches, respectively.
The MAX4890/MAX4891/MAX4892 are available in
space-saving 32- and 36-lead TQFN packages,
significantly reducing the required PC board area.
These devices operate over the -40°C to +85°C temperature range.
Features
♦
♦
♦
♦
♦
Single +3.0V to +3.6V Power-Supply Voltage
Low On-Resistance (RON): 4Ω (typ), 6.5Ω (max)
Ultra-Low On-Capacitance (CON): 6.5pF (typ)
Low < 200ps Bit-to-Bit Skew
-3dB Bandwidth: 1GHz
♦ Optimized Pin-Out for Easy Transformer and PHY
Interface
♦ Built-In LED Switches for Switching Indicators to
Docking Station
♦ Low 450µA (max) Quiescent Current
♦ Bidirectional 8 to 16 Multiplexer/Demultiplexer
♦ Space-Saving Packages
32-Pin, 5mm x 5mm, TQFN Package
36-Pin, 6mm x 6mm, TQFN Package
Ordering Information
Applications
Notebooks and Docking Stations
Servers and Routers with Ethernet Interfaces
PINPACKAGE
PART
LED
SWITCHES
PKG
CODE
MAX4890ETJ
32 TQFN
—
T-3255-4
Board-Level Redundancy Protection
MAX4891ETJ
32 TQFN
1
T-3255-4
SONET/SDH Signal Routing
MAX4892ETX
36 TQFN
3
T-3666-3
T3/E3 Redundancy Protection
All devices are available in the -40°C to +85°C operation temperature range.
Video Switching
1B2
28
1B1
29
0B2
SEL
30
0B1
A0
31
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
N.C.
5
N.C.
6
MAX4890*
9
10
11
12
13
14
15
16
6B2
7B1
6B1
5B2
7B2
4B2
17
N.C.
18
8
A7
7
A5
GND
A4
A6
Typical Operating Circuit appears at end of data sheet.
32
V+
TOP VIEW
A1
Pin Configurations
TQFN
Pin Configurations continued 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
MAX4890/MAX4891/MAX4892
General Description
MAX4890/MAX4891/MAX4892
10/100/1000 Base-T Ethernet LAN Switch
ABSOLUTE MAXIMUM RATINGS
V+ ……………………………………………………… -0.3V to +4V
SEL (Note 1) ………………………………….. -0.3V to (V+ +0.3V)
A_, _B_, LED_, _LED_ .……………………… -0.3V to (V+ +0.3V)
Continuous Current (A_ to _B_) ......................................±120mA
Continuous Current (LED_ to _LED_) .…………………… ±30mA
Peak Current (A_ to _B_)
(pulsed at 1ms, 10% duty cycle) ……………………. ±240mA
Continuous Power Dissipation (TA = +70°C)
32-Pin TQFN (derate 34.5mW/°C above +70°C) …….. 2.76W
36-Pin TQFN (derate 26.3mW/°C above +70°C) …….. 2.11W
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
Note 1: Signals on SEL, exceeding V+ or GND, are clamped by internal diodes. Limit forward-diode current to maximum current
rating.
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 = TMIN to TMAX, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.) (Note 2)
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,
1.5V ≤ VA_ ≤ V+
TA = +25°C
Ω
TMIN to TMAX
6.5
V+ = 3V, I_LED_ = -40mA, 1.5V ≤ VA_ ≤ V+,
MAX4891/MAX4892
V+ = 3V,
IA_= -40mA,
1.5V ≤ VA_ ≤ V+
(Note 3)
40
TA = +25°C
0.5
Ω
1.5
Ω
TMIN to TMAX
2
V+ = 3V, IA_ = -40mA, VA_ = 1.5V, 2.7V
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
±2
kV
Insertion loss with typical transformer,
RL = 100Ω, 1MHz < f < 100MHz, Figure 1
(Note 3)
0.6
dB
SWITCH AC PERFORMANCE
Insertion Loss
ILOS
RLOS1
Return Loss
RLOS2
2
Return loss with
typical transformer,
RL = 100Ω, return
loss, f in MHz,
Figure 2 (Note 3)
1MHz < f < 40MHz
40MHz < f < 100MHz
-19
-13
+20log
(f/80)
_______________________________________________________________________________________
dB
10/100/1000 Base-T Ethernet LAN Switch
MAX4890/MAX4891/MAX4892
ELECTRICAL CHARACTERISTICS (continued)
(V+ = +3V to +3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
VCT1
Crosstalk
VCT2
VCT3
VDCT1
Differential Crosstalk
VDCT2
CONDITIONS
Any switch to any
switch RL = 100Ω,
Figure 3
RL = 100Ω,
Figure 4
VDCT3
MIN
TYP
1MHz < f < 30MHz
-45
30MHz < f < 60MHz
-40
60MHz < f < 100MHz
-35
1MHz < f < 30MHz
-60
30MHz < f < 60MHz
-55
60MHz < f < 100MHz
-50
MAX
UNITS
dB
dB
SWITCH DYNAMICS
On-Channel -3dB Bandwidth
1000
MHz
Off-Capacitance
COFF
BW
RL = 100Ω, Differential pair
f = 1MHz, _B_ inputs
3.5
pF
On-Capacitance
CON
f = 1MHz, _B_ inputs
6.5
pF
pF
Off-Capacitance, LED Switches
COFFLED
f = 1MHz, _LED inputs
20
On-Capacitance, LED Switches
CONLED
f = 1MHz, _LED inputs
22
tON
VA_ = 1V, Figure 5
25
50
ns
tOFF
VA_ = 1V, Figure 5
20
40
ns
Turn-On Time
Turn-Off Time
Propagation Delay
tPLH, tPHL
pF
CL = 10pF, Figure 6
0.15
ns
Output Skew Between Ports
tSK(o)
Skew between A4 and A5 and any other
port, Figure 7
0.01
ns
Output Skew Same Port
tSK(p)
Skew between opposite transitions in same
port
0.07
ns
SWITCH LOGIC
Input-Voltage Low
VIL
Input-Voltage High
VIH
Input-Logic Hysteresis
VHYST
Input Leakage Current
ISEL
Operating Supply-Voltage Range
V+
Quiescent Supply Current
I+
0.8
2.0
100
V+ = 3.6V, VSEL = 0 or V+
V+ = 3.6V, VSEL = 0 or V+
V
mV
-5
+5
uA
3
3.6
V
450
µA
280
Note 2: Specifications at -40°C are guaranteed by design.
Note 3: Guaranteed by design.
_______________________________________________________________________________________
3
Typical Operating Characteristics
(V+ = 3.3V, TA = +25°C, unless otherwise noted.)
20
MAX4890 toc02
MAX4890 toc01
3.8
LED_ ON-RESISTANCE vs. VA_
ON-RESISTANCE vs. VA_
5
4
MAX4890 toc03
ON-RESISTANCE vs. VA_
4.0
V+ = 3.0V
18
16
14
3
RONLED (Ω)
3.6
RON (Ω)
RON (Ω)
V+ = 3.0V, 3.3V, 3.6V
TA = +85°C
TA = +25°C
3.4
2
3.2
1
TA = -40°C
12
10
V+ = 3.3V
V+ = 3.6V
8
6
4
2
0
1.8
2.7
3.6
0
0
1.1
2.2
VA_ (V)
LED_ ON-RESISTANCE vs. TEMPERATURE
12
TA = +25°C
TA = -40°C
6
1400
1200
1000
800
ILA_(ON)
600
400
2
200
2.2
1.1
ILA_(OFF)
-15
10
35
60
TEMPERATURE (°C)
QUIESCENT SUPPLY CURRENT
vs. TEMPERATURE
QUIESCENT SUPPLY CURRENT
vs. LOGIC LEVEL
270
250
230
210
190
0
1000
2.2
3.3
LOGIC THRESHOLD vs. SUPPLY VOLTAGE
800
600
400
1.8
VTH+
1.6
1.4
1.2
VTH-
1.0
0.8
0.6
0.4
200
0.2
170
0
150
-40
-15
10
35
TEMPERATURE (°C)
4
1.1
VA_ (V)
LOGIC THRESHOLD (V)
290
100
85
MAX4890 toc08
310
1200
QUIESCENT SUPPLY CURRENT (µA)
MAX4890 toc07
330
15
5
VA_ (V)
350
20
0
-40
3.3
3.6
25
0
0
2.7
30
MAX4890 toc05
1600
4
0
1.8
CHARGE INJECTION vs. VA_
LEAKAGE CURRENT vs. TEMPERATURE
LEAKAGE CURRENT (pA)
RONLED (Ω)
14
8
0.9
VA_ (V)
1800
MAX4890 toc04
TA = +85°C
16
10
0
VA_ (V)
20
18
3.3
MAX4890 toc06
0.9
CHARGE INJECTION (pC)
0
MAX4890 toc09
3.0
QUIESCENT SUPPLY CURRENT (µA)
MAX4890/MAX4891/MAX4892
10/100/1000 Base-T Ethernet LAN Switch
60
85
0
0
1.1
2.2
LOGIC LEVEL (V)
3.3
3.0
3.1
3.2
3.3
3.4
SUPPLY VOLTAGE (V)
_______________________________________________________________________________________
3.5
3.6
10/100/1000 Base-T Ethernet LAN Switch
RISE-/FALL-TIME PROPAGATION DELAY
vs. SUPPLY VOLTAGE
TURN-ON/-OFF TIME
vs. TEMPERATURE
25
tON/tOFF (ns)
15
tOFF
10
20
15
tOFF
10
5
5
0
150
100
3.4
3.6
-15
10
35
60
3.0
85
PULSE SKEW vs. SUPPLY VOLTAGE
100
MAX4890 toc13
tPLH
tSK(p)
80
PULSE SKEW (ps)
200
150
100
PULSE SKEW vs. TEMPERATURE
tSK(p)
80
60
40
20
tPHL
10
35
60
85
40
0
3.0
3.3
3.6
-40
-15
10
35
60
TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
OUTPUT SKEW
vs. SUPPLY VOLTAGE
OUTPUT SKEW vs. TEMPERATURE
DIFFERENTIAL INSERTION LOSS
vs. FREQUENCY
10
tSK(o)_FALL
10
OUTPUT SKEW (ps)
tSK(o)_FALL
0
tSK(o)_RISE
-10
0
tSK(o)_RISE
-10
3.3
SUPPLY VOLTAGE (V)
3.6
1
0
-1
-2
-3
-4
-5
-20
-20
85
MAX4890 toc18
MAX4890 toc17
20
MAX4890 toc16
20
3.0
60
20
0
50
3.6
100
PULSE SKEW (ps)
250
-15
3.3
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
RISE-/FALL-TIME PROPAGATION DELAY
vs. TEMPERATURE
-40
tPHL
50
-40
MAX4890 toc14
3.2
SUPPLY VOLTAGE (V)
OUTPUT RISE-/FALL-TIME DELAY (ps)
200
0
3.0
OUTPUT SKEW (ps)
tPLH
DIFFERENTIAL INSERTION LOSS (dB)
tON/tOFF (ns)
tON
250
MAX4890 toc12
tON
MAX4890 toc15
20
MAX4890 toc11
30
MAX4890 toc10
25
OUTPUT RISE/FALL-TIME DELAY (ps)
TURN-ON/-OFF TIME
vs. SUPPLY VOLTAGE
-40
-15
10
35
TEMPERATURE (°C)
60
85
1
10
100
FREQUENCY (MHz)
_______________________________________________________________________________________
5
MAX4890/MAX4891/MAX4892
Typical Operating Characteristics (continued)
(V+ = 3.3V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(V+ = 3.3V, TA = +25°C, unless otherwise noted.)
-20
-30
-40
1
MAX4890 toc20
-10
-20
-30
-40
-50
-60
-70
-80
-20
-30
-40
-50
-60
-70
-80
-90
-100
-100
1
1
100
10
FREQUENCY (MHz)
10
FREQUENCY (MHz)
FREQUENCY (MHz)
SINGLE-ENDED CROSSTALK
vs. FREQUENCY
SINGLE-ENDED INSERTION LOSS
vs. FREQUENCY
-30
-40
-50
-60
-70
-80
MAX4890 toc23
-20
0
SINGLE-ENDED INSERTION LOSS (dB)
MAX4890 toc22
0
-10
SINGLE-ENDED CROSSTALK (dB)
-10
-90
100
10
0
SINGLE-ENDED OFF-ISOLATION (dB)
-10
0
DIFFERENTIAL CROSSTALK (dB)
MAX4890 toc19
0
SINGLE-ENDED OFF-ISOLATION
vs. FREQUENCY
DIFFERENTIAL CROSSTALK
vs. FREQUENCY
MAX4890 toc21
DIFFERENTIAL RETURN LOSS
vs. FREQUENCY
DIFFERENTIAL RETURN LOSS (dB)
MAX4890/MAX4891/MAX4892
10/100/1000 Base-T Ethernet LAN Switch
-1
-2
-3
-4
-90
-100
-5
1
10
FREQUENCY (MHz)
6
100
1
10
100
1000
FREQUENCY (MHz)
_______________________________________________________________________________________
100
10/100/1000 Base-T Ethernet LAN Switch
PIN
MAX4890
MAX4891
31, 32, 1, 2, 31, 32, 1, 2,
7–10
7–10
MAX4892
36, 1, 2, 3,
7–10
NAME
A0–A7
FUNCTION
Differential PHY Interface Pair. Connects to the Ethernet PHY.
—
3
4
LED0
LED0 Input
—
4
5
0LED1
0LED1 Output. Connects LED0 to 0LED1 when SEL = 0.
0LED2 Output. Connects LED0 to 0LED2 when SEL = 1.
—
5
6
0LED2
3–6, 12
6, 12
—
N.C.
No Connection. Not internally connected.
11
11
11
GND
Ground
—
—
12
LED1
LED1 Input
—
—
13
1LED1
1LED1 Output. Connects LED1 to 1LED1 when SEL = 0.
—
—
14
1LED2
1LED2 Output. Connects LED1 to 1LED2 when SEL = 1.
13, 14, 17,
18, 21, 22,
25, 26
13, 14, 17,
18, 21, 22,
25, 26
15, 16, 19,
20, 23, 24,
28, 29
7B2–0B2
B2 Differential Transformer Pair
15, 16, 19,
20, 23, 24,
27, 28
15, 16, 19,
20, 23, 24,
27, 28
17, 18, 21,
22, 25, 26,
30, 31
7B1–0B1
B1 Differential Transformer Pair
29
29
27
SEL
—
—
32
2LED2
2LED2 Output. Connects LED2 to 2LED2 when SEL = 1.
—
—
33
2LED1
2LED1 Output. Connects LED2 to 2LED1 when SEL = 0.
Select Input. Selects switch connection. See the Truth Table (Table 1).
—
—
34
LED2
30
30
35
V+
Positive Supply-Voltage Input
LED2 Input
EP
EP
EP
EP
Exposed Paddle. Not internally connected. Leave unconnected or connect to
ground.
_______________________________________________________________________________________
7
MAX4890/MAX4891/MAX4892
Pin Description
MAX4890/MAX4891/MAX4892
10/100/1000 Base-T Ethernet LAN Switch
Test Circuits
MAX4892
36 TQFN
INSERTION LOSS
1
NETWORK
ANALYZER
MINI CKT
BALUN
50Ω
TRACE
6
50Ω
0B1 TRACE
A0
36
31
5
50Ω
TRACE 3
50Ω
TRACE
4
50:100
50Ω
3B1 TRACE
30
A1
1
5
PULSE H5007
24-PIN PACKAGE
20
4
21
6
19
CB1
50Ω
TRACE
3
5
50Ω
TRACE
50Ω
1 TRACE
6
100:50
R1
75Ω
C2
0.01µF
4
MINI CKT
BALUN
NETWORK
ANALYZER
CB3
C3
1000pF
Figure 1. Differential Insertion Loss
RETURN LOSS
MAX4892
36 TQFN
R16
49.9Ω
R17
49.9Ω
50Ω
TRACE
A2
2
A3
3
5
3B1
25
50Ω
TRACE
PULSE H5007
24-PIN PACKAGE
20
4
21
6
19
C2
0.01µF
50Ω
TRACE
4
MINI CKT
BALUN
3
5
50Ω
TRACE
R1
75Ω
50Ω
1 TRACE
6
100:50
CB3
C3
1000pF
Figure 2. Differential Return Loss
8
_______________________________________________________________________________________
NETWORK
ANALYZER
10/100/1000 Base-T Ethernet LAN Switch
MAX4892
SINGLE-ENDED BANDWIDTH
NETWORK
ANALYZER
50Ω TRACE
SINGLE-ENDED CROSSTALK
NETWORK
ANALYZER
50Ω TRACE
NETWORK
ANALYZER
50Ω TRACE
A2
2
50Ω TRACE
NETWORK
ANALYZER
2B1
26
R13
49.9Ω
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 3. Single-Ended Bandwidth, Crosstalk and Off-Isolation
Detailed Description
The MAX4890/MAX4891/MAX4892 are high-speed analog switches targeted for 10/100/1000 Base-T applications. In a typical application, the MAX4890/MAX4891/
MAX4892 switch the signals from two separate interface transformers and connect the signals to a single
10/100/1000 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 MAX4891 and MAX4892 also include LED
switches that allow the LED output signals to be routed
to a docking station along with the Ethernet signals.
See the Functional Diagrams.
The MAX4890/MAX4891/MAX4892 switches provide
an extremely low capacitance and on-resistance
to meet Ethernet insertion and return-loss specifications. The MAX4891/MAX4892 feature one and three
built-in LED switches, respectively.
The MAX4890/MAX4891/MAX4892 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 R ON
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 MAX4890/
MAX4891/MAX4892 include internal flyback capacitors,
reducing design time, board space, and cost.
Digital Control Inputs
The MAX4890/MAX4891/MAX4892 provide a single
digital control SEL. SEL controls the switches as well as
the LED switches as shown in Table 1.
Table 1. Truth Table
SEL
CONNECTION
0
A_ to _B1, LED_ to _LED1
1
A_ to _B2, LED_ to _LED2
_______________________________________________________________________________________
9
MAX4890/MAX4891/MAX4892
Test Circuits (continued)
MAX4890/MAX4891/MAX4892
10/100/1000 Base-T Ethernet LAN Switch
DIFFERENTIAL CROSSTALK TRANSMIT CKT
1
MINI CKT
BALUN
MAX4892
36-TQFN AB1
22
A4
6
7
NETWORK
ANALYZER
5B1
21
50Ω
TRACE 3
R3
49.9Ω
A5
4
8
50:100
R4
49.9Ω
CB4
DIFFERENTIAL CROSSTALK RECEIVE CKT
NETWORK
ANALYZER
50Ω
TRACE
1
MINI CKT
BALUN
6
50Ω
TRACE
9
5
50Ω
TRACE A7
10
4
3
6B1
18
A6
50:100
7B1
17
R3
49.9Ω
R4
49.9Ω
CB5
Figure 4. Differential Crosstalk
Analog Signal Levels
Line-Card Redundancy (Ethernet T3/E3)
The on-resistance of the MAX4890/MAX4891/MAX4892
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.
Figure 10 shows the MAX4890/MAX4891/MAX4892 in a
line-card redundancy configuration.
ESD Protection
The MAX4890/MAX4891/MAX4892 are characterized
using the Human Body Model for ±2kV of ESD protection. Figure 8 shows the Human Body Model, and Figure
9 shows the current waveform the Human Body Model
generates when discharged into a low-impedance load.
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.
Applications Information
Typical Operating Circuit
The Typical Operating Circuit depicts the MAX4890/
MAX4891/MAX4892 in a 10/100/1000 Base-T docking
station application.
10
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 designcontrolled-impedance printed circuit board traces as
short as possible. Ensure that bypass capacitors are as
close to the device as possible. Use large ground
planes where possible.
______________________________________________________________________________________
10/100/1000 Base-T Ethernet LAN Switch
2.5V
1.25V
MAX4890/MAX4891/MAX4892
SEL
3.0V
2.0V
1.25V
0V
A_
1.0V
tON
A_
tPHL
tPLH
90%
tOFF
VOH
90%
0V
2.0V
tON
_B_
VOL
A_
90%
PULSE SKEW = tSK(p) = |tPHL - tPLH|
tOFF
THE MAX4890/MAX4891/MAX4892 SWITCHES ARE FULLY BIDIRECTIONAL.
10%
0V
Figure 5. ENABLE and DISABLE Times
Figure 6. Propagation Delay Times
3.0V
2.0V
A_
1.0V
RC
1MΩ
tPHLX
tPLHX
CHARGE-CURRENT
LIMIT RESISTOR
VOH
2.0V
_B_
HIGHVOLTAGE
DC
SOURCE
VOL
Cs
100pF
RD
1500Ω
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
tPHLY
tPLHY
VOH
2.0V
_B_
VOL
PULSE SKEW = tSK(p) = |tPHLY - tPLHX| OR |tPHLy - tPHLx|
THE MAX4890/MAX4891/MAX4892 SWITCHES ARE FULLY BIDIRECTIONAL.
Figure 7. Output Skew
Figure 8. Human Body ESD Test Model
______________________________________________________________________________________
11
MAX4890/MAX4891/MAX4892
10/100/1000 Base-T Ethernet LAN Switch
IP 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
ETHERNET
PHYs
OR
T3/E3 LIUs
PRIMARY CARD
MAX4890
MAX4891
MAX4892
AMPERES
PROTECTION
SWITCH
36.8%
10%
0
0
tRL
TIME
tDL
CURRENT WAVEFORM
ETHERNET
PHYs
OR
T3/E3 LIUs
TRANSFORMER
SWITCHING CARD
PROTECTION CARD
Figure 9. Human Body Model Current Waveform
12
Figure 10. Typical Application for Line-Card Redundancy
______________________________________________________________________________________
10/100/1000 Base-T Ethernet LAN Switch
DOCKING STATION
TRANSFORMER
RJ-45
LED
CONNECTOR
NOTEBOOK
0B2
1B2
2B2
3B2
TRD1_P
TRD1_N
A2
A3
TRD2_P
TRD2_N
A4
A5
TRD3_P
TRD3_N
A6
A7
ETHERNET
PHY/MAC
LED_OUT
4B2
5B2
_LED2
0B1
1B1
2B1
3B1
4B1
5B1
RJ-45
6B1
7B1
LED_
SEL
SEL_DOCK
6B2
7B2
TRANSFORMER
A0
A1
MAX4890/MAX4891/MAX4892
TRD0_P
TRD0_N
_LED1
LED
______________________________________________________________________________________
13
MAX4890/MAX4891/MAX4892
Typical Operating Circuit
10/100/1000 Base-T Ethernet LAN Switch
MAX4890/MAX4891/MAX4892
Functional Diagrams
A0
A1
0B1
1B1
A0
0B1
1B1
A1
0B2
0B2
1B2
1B2
A2
2B1
A2
2B1
A3
3B2
A3
3B2
2B1
2B1
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
SEL
MAX4890
SEL
MAX4891
14
______________________________________________________________________________________
10/100/1000 Base-T Ethernet LAN Switch
A0
0B1
1B1
A1
0B2
1B2
A2
2B1
A3
3B2
2B1
3B2
A4
4B1
A5
5B1
4B2
5B2
A6
6B1
A7
7B1
6B2
7B2
LED0
0LED1
0LED2
LED1
1LED1
1LED2
LED2
2LED1
2LED2
SEL
MAX4892
______________________________________________________________________________________
15
MAX4890/MAX4891/MAX4892
Functional Diagrams (continued)
10/100/1000 Base-T Ethernet LAN Switch
0LED1
4
21
3B2
0LED2
MAX4891
5
20
4B1
N.C.
6
19
5B1
A4
7
18
4B2
17
13
14
15
16
7B1
6B1
GND
12
6B2
11
7B2
10
N.C.
9
A7
8
A6
A5
5B2
TQFN
2LED1
2LED2
0B1
1B1
0B2
1B2
33
32
31
30
29
28
V+
LED2
2B1
A3
3
25
3B1
LED0
4
24
2B2
0LED1
5
23
3B2
0LED2
6
22
4B1
A4
7
21
5B1
A5
8
20
4B2
A6
9
19
5B2
MAX4892
18
2B2
SEL
26
6B1
22
27
2
16
3
1
A2
17
LED0
A1
7B1
3B1
6B2
23
15
2
7B2
A3
14
2B1
13
24
1LED2
1
1LED1
A2
34
25
12
1B2
26
LED1
0B2
27
A0
1B1
28
35
0B1
29
36
SEL
30
11
V+
31
10
A0
32
A7
A1
TOP VIEW
GND
MAX4890/MAX4891/MAX4892
Pin Configurations (continued)
TQFN
Chip Information
TRANSISTOR COUNT: 948
PROCESS: BiCMOS
16
______________________________________________________________________________________
10/100/1000 Base-T Ethernet LAN Switch
QFN THIN.EPS
D2
D
MARKING
b
C
L
0.10 M C A B
D2/2
D/2
k
L
XXXXX
E/2
E2/2
C
L
(NE-1) X e
E
DETAIL A
PIN # 1
I.D.
E2
PIN # 1 I.D.
0.35x45°
e/2
e
(ND-1) X e
DETAIL B
e
L1
L
C
L
C
L
L
L
e
e
0.10 C
A
C
0.08 C
A1 A3
PACKAGE OUTLINE,
16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm
21-0140
-DRAWING NOT TO SCALE-
COMMON DIMENSIONS
A1
A3
b
D
E
e
k
L
L1
N
ND
NE
JEDEC
0.70 0.75 0.80 0.70 0.75 0.80 0.70 0.75 0.80 0.70 0.75 0.80 0.70 0.75 0.80
0
0.02 0.05
0
0.02 0.05
0.20 REF.
0.20 REF.
0.25 0.30 0.35 0.25 0.30 0.35
4.90 5.00 5.10 4.90 5.00 5.10
4.90 5.00 5.10 4.90 5.00 5.10
0.80 BSC.
0.65 BSC.
0.25 - 0.25 -
0
0.02 0.05
0
0.02 0.05
0
0.02 0.05
0.20 REF.
0.20 REF.
0.20 REF.
0.20 0.25 0.30 0.20 0.25 0.30 0.15 0.20 0.25
4.90 5.00 5.10 4.90 5.00 5.10 4.90 5.00 5.10
4.90 5.00 5.10 4.90 5.00 5.10 4.90 5.00 5.10
0.40 BSC.
0.50 BSC.
0.50 BSC.
- 0.25
- 0.25 0.35 0.45
0.25 -
0.30 0.40 0.50 0.45 0.55 0.65 0.45 0.55 0.65 0.30 0.40 0.50 0.40 0.50 0.60
- 0.30 0.40 0.50
16
4
4
20
5
5
WHHB
WHHC
1
2
EXPOSED PAD VARIATIONS
PKG.
16L 5x5
20L 5x5
28L 5x5
32L 5x5
40L 5x5
SYMBOL MIN. NOM. MAX. MIN. NOM. MAX. MIN. NOM. MAX. MIN. NOM. MAX. MIN. NOM. MAX.
A
H
28
7
7
WHHD-1
32
8
8
40
10
10
WHHD-2
-----
NOTES:
1. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994.
2. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES.
3. N IS THE TOTAL NUMBER OF TERMINALS.
4. THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL
CONFORM TO JESD 95-1 SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE
OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE TERMINAL #1
IDENTIFIER MAY BE EITHER A MOLD OR MARKED FEATURE.
5. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN
0.25 mm AND 0.30 mm FROM TERMINAL TIP.
D2
L
E2
PKG.
CODES
MIN.
NOM. MAX.
T1655-1
T1655-2
T1655N-1
3.00
3.00
3.00
3.10 3.20 3.00
3.10 3.20 3.00
3.10 3.20 3.00
3.10
3.10
3.10
3.20
3.20
3.20
T2055-2
T2055-3
T2055-4
3.00
3.00
3.00
3.10 3.20 3.00
3.10 3.20 3.00
3.10 3.20 3.00
3.10
3.10
3.10
3.20
3.20
3.20
T2055-5
T2855-1
T2855-2
T2855-3
T2855-4
T2855-5
T2855-6
T2855-7
T2855-8
T2855N-1
T3255-2
T3255-3
T3255-4
T3255N-1
3.15
3.15
2.60
3.15
2.60
2.60
3.15
2.60
3.15
3.15
3.00
3.00
3.00
3.00
3.25
3.25
2.70
3.25
2.70
2.70
3.25
2.70
3.25
3.25
3.10
3.10
3.10
3.10
3.15
3.15
2.60
3.15
2.60
2.60
3.15
2.60
3.15
3.15
3.00
3.00
3.00
3.00
3.25
3.25
2.70
3.25
2.70
2.70
3.25
2.70
3.25
3.25
3.10
3.10
3.10
3.10
3.35
3.35
2.80
3.35
2.80
2.80
3.35
2.80
3.35
3.35
3.20
3.20
3.20
3.20
T4055-1
3.20
3.30 3.40 3.20
3.30
3.40
3.35
3.35
2.80
3.35
2.80
2.80
3.35
2.80
3.35
3.35
3.20
3.20
3.20
3.20
MIN.
NOM. MAX.
±0.15
**
**
**
**
**
**
0.40
DOWN
BONDS
ALLOWED
NO
YES
NO
NO
YES
NO
YES
**
NO
NO
YES
YES
NO
**
**
0.40
**
**
**
**
**
NO
YES
YES
NO
NO
YES
NO
NO
**
YES
**
**
**
**
** SEE COMMON DIMENSIONS TABLE
6. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY.
7. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION.
8. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS.
9. DRAWING CONFORMS TO JEDEC MO220, EXCEPT EXPOSED PAD DIMENSION FOR T2855-1,
T2855-3, AND T2855-6.
10. WARPAGE SHALL NOT EXCEED 0.10 mm.
11. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY.
12. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY.
13. LEAD CENTERLINES TO BE AT TRUE POSITION AS DEFINED BY BASIC DIMENSION "e", ±0.05.
-DRAWING NOT TO SCALE-
PACKAGE OUTLINE,
16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm
21-0140
H
2
2
______________________________________________________________________________________
17
MAX4890/MAX4891/MAX4892
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.)
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.)
QFN THIN 6x6x0.8.EPS
MAX4890/MAX4891/MAX4892
10/100/1000 Base-T Ethernet LAN Switch
D2
D
CL
D/2
b
D2/2
k
E/2
E2/2
(NE-1) X e
E
CL
E2
k
e
L
(ND-1) X e
e
L
CL
CL
L1
L
L
e
A1
A2
e
A
PACKAGE OUTLINE
36, 40, 48L THIN QFN, 6x6x0.8mm
21-0141
E
1
2
NOTES:
1. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994.
2. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES.
3. N IS THE TOTAL NUMBER OF TERMINALS.
4. THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL CONFORM TO JESD 95-1
SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE
ZONE INDICATED. THE TERMINAL #1 IDENTIFIER MAY BE EITHER A MOLD OR MARKED FEATURE.
5. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN 0.25 mm AND 0.30 mm
FROM TERMINAL TIP.
6. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY.
7. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION.
8. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS.
9. DRAWING CONFORMS TO JEDEC MO220, EXCEPT FOR 0.4mm LEAD PITCH PACKAGE T4866-1.
10. WARPAGE SHALL NOT EXCEED 0.10 mm.
PACKAGE OUTLINE
36, 40, 48L THIN QFN, 6x6x0.8mm
21-0141
E
2
2
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.
18 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2005 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products, Inc.