Analog Signal Levels

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, allow-

ing A_ and _B_ to be configured as either inputs or out-

puts.

ESD Protection

The MAX4890/MAX4891/MAX4892 are characterized

using the Human Body Model for ±2kV of ESD protec-

tion. 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.

Line-Card Redundancy (Ethernet T3/E3)

Figure 10 shows the MAX4890/MAX4891/MAX4892 in a

line-card redundancy configuration.

Power-Supply Sequencing and

Overvoltage Protection

Caution: Do not exceed the absolute maximum ratings.

Stresses beyond the listed ratings may cause perma-

nent 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 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

10

______________________________________________________________________________________

Figure 4. Differential Crosstalk

1

3

MINI CKT

BALUN

6

4

NETWORK

ANALYZER

R4

49.9

Ω

R3

49.9

Ω

1

3

MINI CKT

BALUN

6

4

R4

49.9

Ω

R3

49.9

Ω

50

Ω

TRACE

50:100

NETWORK

ANALYZER

50

Ω

TRACE

5

50:100

CB5

CB4

50

Ω

TRACE

50

Ω

TRACE

A4

7

A5

8

AB1

22

5B1

21

6B1

18

7B1

17

A6

9

A7

10

DIFFERENTIAL CROSSTALK TRANSMIT CKT

DIFFERENTIAL CROSSTALK RECEIVE CKT

MAX4892

36-TQFN