MAXIM MAX4928A, MAX4928B User Manual

General Description

The MAX4928A/MAX4928B high-speed passive switches route PCI Express

(PCIe) data and/or DisplayPort™ signals between two possible destinations in desktop or laptop PCs. The MAX4928A is intended to be used with the ATX form factor desktop PCs, while the MAX4928B is expected to be used in the BTX form factor.

The MAX4928A/MAX4928B are hex double-pole/double-throw (6 x DPDT) switches. The MAX4928A/ MAX4928B feature a single digital control input (SEL) to switch signal paths and a latch input (LE) that holds the switches in a given state.

The MAX4928A/MAX4928B are fully specified to operate from a single +3.3V (typ) power supply. The MAX4928A/MAX4928B are available in an industry standard 5mm x 11mm, 56-pin TQFN package. Both devices operate over the -40°C to +85°C extended temperature range.

Applications

Desktop PCs

Notebook PCs

Features

♦ Single +3.3V Power Supply Voltage

♦ Supports PCIe Gen I, Gen II, and DisplayPort

Data Rates > 5Gbps

♦ Excellent Return Loss > 12dB at 2.5GHz

♦ Six Bidirectional Pairs of Switches

All Switching in One Device

♦ Low 850µA (max) Supply Current

♦ Small 5mm x 11mm, 56-Pin TQFN Package

♦ Industry-Standard Pinouts

MAX4928A/MAX4928B

DisplayPort/PCIe Passive Switches

________________________________________________________________

Maxim Integrated Products

19-4030; Rev 1; 8/08

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Typical Operating Circuit appears at end of data sheet.

MAX4928A

21 22 23 24 25 26 27 28

*EP

GND

TX0+

TX0-

TX1+

TX1-

GND

HPD2

HPD1

AUX-

AUX+

GND

54 5356 55 52 51 50 49

OUT+

OUT-

X+

GND

IN3-

IN3+

SEL

GND

X-

IN2-

IN2+

IN1-

IN1+

IN0-

IN0+

GND

D3+

D3-

GND

D2-

D2+

D1-

RX1+

RX1-

GND

RX0-

RX0+

D1+

D0-

D0+

TX3-

TX3+

TX2-

TX2+

GND

*CONNECT EXPOSED PADDLE TO GND.

TQFN

TOP VIEW

MAX4928B

21 22 23 24 25 26 27 28

*EP

GND

D0+

D0-

D1+

D1-

GND

RX1-

RX1+

RX0-

RX0+

GND

54 5356 55 52 51 50 49

IN3+

IN3-

OUT+

GND

IN2-

IN2+

X+

X-

GND

OUT-

IN1-

IN1+

IN0-

IN0+

SEL

GND

TX3+

TX3-

GND

TX2-

TX2+

TX1-

HPD1

HPD2

GND

AUX-

AUX+

TX1+

TX0-

TX0+

D3-

D3+

D2-

D2+

GND

TQFN

Pin Configurations

PCI Express is a registered trademark of PCI-SIG.

DisplayPort is a trademark of Video Electronics Standards Association (VESA).

PART TEMP RANGE PIN-PACKAGE

MAX4928AETN+

-40°C to +85°F 56 TQFN-EP

MAX4928BETN+

-40°C to +85°F 56 TQFN-EP

Ordering Information

Denotes a lead-free package/RoHS-Compliant package.

EP = Exposed paddle.

MAX4928A/MAX4928B

DisplayPort/PCIe Passive Switches

2 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS

(VDD= +3.3V ±10%, TA=T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VDD= +3.3V, TA= +25°C, unless otherwise

noted.) (Note 3)

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.

PARAMETER SYMBOL CONDITIONS

ANALOG SWITCH

Analog Signal Range

IN_, X_, OUT_,

D_, TX_, HPD_,

RX_, AUX_

(VDD -

Voltage Between IN and D/TX, X and HPD/RX1, and OUT and AUX/RX0

IN_

- V

TX_

IN_

- VD_|,

- V

HPD_

OUT_

AUX_

01.8V

On-Resistance R

IN_

= IX_ = I

OUT_

= 15mA, VD_, V

TX_

HPD_

, V

AUX_

, or V

RX_

= 0V, +1.2V

8 Ω

On-Resistance Match

Between Pairs of Same Channel

ΔR

D D

= + 3.0V , I

I N _

= I

X _

= I

OU T _

= 15m A,

D _, V T X _

, V

H P D _

, V

A U X _

, or V

R X _

= 0V

( N otes 4, 5)

0.1 2

On-Resistance Match Between Channels

ΔR

D D

= + 3.0V , I

I N _

= I

X _

= I

OU T _

= 15m A,

D _, V T X _

, V

H P D _

, V

A U X _

, or V

R X _

= 0V

( N otes 4, 5)

1.5 4

On-Resistance Flatness R

FLAT(ON)

D D

= + 3.0V , I

I N _

= I

X _

= I

OU T _

= 15m A,

D _, V T X _

, V

H P D _

, V

A U X _

, or V

R X _

= 0V ,

+ 1.2V ( N otes 5, 6)

0.3 1.5 Ω

ABSOLUTE MAXIMUM RATINGS

(All voltages referenced to GND, unless otherwise noted.) V

...........................................................................-0.3V to +4V

LE, SEL, IN_, X_, OUT_, D_, TX_, HPD_, RX_, AUX_

(Note 1) ...............................................-0.3V to + (V

+ 0.3V)

IN_

- V

TX_

|, |V

IN_

- VD_|, |VX_- V

HPD_

|, |VX_- V

RX1_

OUT_

- V

AUX_

|, |V

OUT_

- V

RX0_

| (Note 1)...................0 to +2V

Continuous Current (IN_ to D_/TX_, X_ to HPD_/RX1_,

OUT_ to AUX_/RX0_ .....................................................±70mA

Peak Current (IN_ to D_/TX_, X_ to HPD_/RX1_, OUT_ to

AUX_/RX0_) (pulsed at 1ms, 10% duty cycle) .............±70mA

Continuous Current (LE, SEL)...........................................±30mA

Peak Current (LE, SEL)

(pulsed at 1ms, 10% duty cycle)..................................±70mA

Continuous Power Dissipation (T

= +70°C) for Multilayer Board

56-Pin TQFN (derate 41.0mW/°C above +70°C) .......3279mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Package Junction-to-Ambient Thermal Resistance (θ

)

(Note 2) .....................................................................24.4°C/W

Package Junction-to-Case Thermal Resistance (θ

)

(Note 2) .......................................................................1.5°C/W

Lead Temperature (soldering) .........................................+300°C

Note 1: Signals on IN_, X_, OUT_, D_, TX_, HPD_, RX_, or AUX_, LE, SEL exceeding V

or GND are clamped by internal diodes.

Limit forward-diode current to maximum current rating.

Note 2: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a 4-layer

board. For detailed information on package thermal considerations, see www.maxim-ic.com/thermal-tutorial.

MIN TYP MAX UNITS

|VX_ - V

OUT_

- V

RX1_

RX0_

-0.1

1.8)

MAX4928A/MAX4928B

DisplayPort/PCIe Passive Switches

_______________________________________________________________________________________ 3

PARAMETER SYMBOL CONDITIONS

D_ or TX_/ HPD_ or RX1_/ AUX_ or RX0_ Off-Leakage Current

D_ (OFF)

TX_ (OFF)

HPD_ (OFF)

RX1_ (OFF)

AUX_ (OFF)

RX0_ (OFF)

D D

= + 3.6V , V

I N _

= V

X _

= V

OU T _

= 0V ,

+ 1.2V ; V

D _

or V

T X _

, V

H P D _

or V

R X 1 _

A U X _

or V

R X 0 _

= + 1.2V , 0V

-1 +1

IN_/X_/OUT_ On-Leakage Current

IN_ (ON)

X_ (ON)

OUT_ (ON)

D D

= + 3.6V , V

I N _

= V

X _

= V

OU T _

= 0V ,

+ 1.2V ; V

D _

or V

T X _

= V

I N _

unconnected , V

H P D _

or V

R X 1 _

= V

X _

unconnected , V

A U X _

or V

R X 0 _

= V

OU T _

or unconnected

-1 +1

µA

DIGITAL SIGNALS

SEL to Switch Turn-On Time t

ON_SEL

VD_ or V

TX_

= +1.0V, RL = 50Ω,

HPD_

or V

RX1_

= +1.0V, R

= 50Ω,

AUX_

or V

RX0_

= +1.0V, RL = 50Ω,

LE = V

, CL = 100pf (Figure 1)

55 120 ns

SEL to Switch Turn-Off Time t

OFF_SEL

VD_ or V

TX_

= +1.0V, RL = 50Ω,

HPD_

or V

RX1_

= +1.0V, RL = 50Ω,

AUX_

or V

RX0_

= +1.0V, R

= 50Ω,

LE = V

, CL = 100pf (Figure 1)

850ns

LE Setup Time SEL to LE

VD_ or V

TX_

= +1.0V, RL = 50Ω,

HPD_

or V

RX1_

= +1.0V, R

= 50Ω,

AUX_

or V

RX0_

= +1.0V, R

= 50Ω

(Figure 1)

2ns

LE Hold Time SEL to LE

HOLD

VD_ or V

TX_

= +1.0V, RL = 50Ω,

HPD_

or V

RX1_

= +1.0V, RL = 50Ω,

AUX_

or V

RX0_

= +1.0V, RL = 50Ω,

(Figure 1)

2ns

LE Minimum Pulse-Width Low t

VD_ or V

TX_

= +1.0V, RL = 50Ω,

HPD_

or V

RX1_

= +1.0V, R

= 50Ω,

AUX_

or V

RX0_

= +1.0V, RL = 50Ω

(Figure 1)

40 ns

f = 2.5GHz

f = 5.0GHz

Differential Insertion Loss (Figure 2)

DD21

f = 7.5GHz

f = 2.5GHz -40

f = 5.0GHz -23Differential Crosstalk (Figure 2) S

DDCTK

f = 7.5GHz -28

Differential Off-Isolation S

DD21_OFF

f = 3.0GHz -22 dB

f = 2.8GHz -21

f = 5.0GHz -8

Differential Return Loss (Figure 2)

DD11

f = 7.5GHz -7

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +3.3V ±10%, TA=T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VDD= +3.3V, TA= +25°C, unless otherwise

noted.) (Note 3)

MIN TYP MAX UNITS

-1.5

-3.3

-4.9

MAX4928A/MAX4928B

DisplayPort/PCIe Passive Switches

4 _______________________________________________________________________________________

PARAMETER SYMBOL CONDITIONS

Signal Data Rate BR RS = RL = 100Ω balanced 10

Differential -3dB Bandwidth DBW RS = RL = 100Ω balanced 5 GHz

LOGIC INPUT (LE, SEL)

Input Logic-High V

1.4 V

Input Logic-Low V

0.5 V

Input Logic Hysteresis V

HYST

100 mV

Input Leakage Current I

VIN = 0 or V

-1 +1 µA

POWER SUPPLY

Power Supply Range V

3.0 3.6 V

VDD Supply Current I

VIN = 0 or V

µA

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +3.3V ±10%, TA=T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VDD= +3.3V, TA= +25°C, unless otherwise

noted.) (Note 3)

Note 3: All units are 100% production tested at T

= +85°C. Limits over the operating temperature range are guaranteed by design

and characterization and are not production tested.

Note 4: ΔR

= R

ON (MAX)

- R

ON (MIN)

Note 5: Guaranteed by design. Not production tested. Note 6: Flatness is defined as the difference between the maximum and minimum value of on-resistance as measured over the

specified analog signal range.

MIN TYP MAX UNITS

Gbps

850

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