MAX3082EPA原理图各脚功能电路原理芯片引脚定义引脚图及功能-中国IC网-芯三七

19-1138; Rev 1; 12/97

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

Ge n e ra l De s c rip t io n

Fe a t u re s

The MAX3080–MAX3089 high-speed transceivers for

RS-485/RS-422 communication contain one driver and

one receiver. These devices feature fail-safe circuitry,

which guarantees a logic-high receiver output when the

receiver inputs are open or shorted. This means that

the receiver output will be a logic high if all transmitters

on a terminated bus are disabled (high impedance).

The MAX3080/MAX3081/MAX3082 feature reduced

slew-rate drivers that minimize EMI and reduce reflec-

tions caused by improperly terminated cables, allowing

e rror-fre e d a ta tra ns mis s ion up to 115kb p s . The

MAX3083/MAX3084/MAX3085 offer higher driver out-

put slew-rate limits, allowing transmit speeds up to

500kbps. The MAX3086/MAX3087/MAX3088’s driver

slew rates are not limited, making transmit speeds up

to 10Mb p s p os s ib le . The MAX3089’s s le w ra te is

selectable between 115kbps, 500kbps, and 10Mbps

b y d riving a s e le c tor p in with a s ing le thre e -s ta te

driver.

♦ True Fail-Safe Receiver While Maintaining

EIA/TIA-485 Compatibility

♦ Enhanced Slew-Rate Limiting Facilitates

Error-Free Data Transmission

(MAX3080–MAX3085/MAX3089)

♦ 1nA Low-Current Shutdown Mode (except

MAX3081/MAX3084/MAX3087)

♦ Pin-Selectable Full/Half-Duplex Operation

(MAX3089)

♦ Phase Controls to Correct for Twisted-Pair

Reversal (MAX3089)

♦ Allow Up to 256 Transceivers on the Bus

Ap p lic a t io n s

RS-422/RS-485 Communications

Level Translators

These transceivers typically draw 375µA of supply

current when unloaded, or when fully loaded with the

drivers disabled.

Transceivers for EMI-Sensitive Applications

Industrial-Control Local Area Networks

All devices have a 1/8-unit-load receiver input imped-

ance that allows up to 256 transceivers on the bus. The

MAX3082/MAX3085/MAX3088 are intended for half-

duplex communications, while the MAX3080/MAX3081/

MAX3083/MAX3084/MAX3086/MAX3087 are intended

for full-duplex communications. The MAX3089 is selec-

table between half-duplex and full-duplex operation. It

also features independently programmable receiver

and transmitter output phase via separate pins.

Ord e rin g In fo rm a t io n

PART

TEMP. RANGE

0°C to +70°C

-40°C to +85°C

PIN-PACKAGE

14 Plastic DIP

14 SO

MAX3080CPD

MAX3080CSD

MAX3080EPD

MAX3080ESD

14 Plastic DIP

14 SO

Ordering Information continued on last page.

S e le c t io n Ta b le

Data

Rate

(Mbps)

Slew

Rate

Limited

Low-

Power

Shutdown

Receiver/ Quiescent Transceivers

Industry-

Standard

Pinout

Half/Full

Duplex

Count

Part

Driver

Current

(µA)

On

Enable

Bus

MAX3080

MAX3081

MAX3082

MAX3083

MAX3084

MAX3085

MAX3086

MAX3087

MAX3088

Full

Half

Full

Half

Full

Half

0.115

0.5

Yes

No

Yes

No

Yes

No

375

256

14

8

75180

75179

75176

75180

75179

75176

75180

75179

75176

75180*

Yes

No

Yes

No

8

14

8

0.5

Yes

No

Yes

No

8

10

14

8

10

No

10

No

Yes

8

MAX3089 Selectable Selectable Selectable

14

*Pin-compatible with 75180, with additional features implemented using pins 1, 6, 8, and 13.

________________________________________________________________ Maxim Integrated Products

1

For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.

For small orders, phone 1-800-835-8769.

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

ABSOLUTE MAXIMUM RATINGS

Supply Voltage (V ) ............................................................+7V

Continuous Power Dissipation

CC

Control Input Voltage (RE, DE)...................-0.3V to (V + 0.3V)

Special Input Voltage

8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) ...727mW

8-Pin SO (derate 5.88mW/°C above +70°C)................471mW

14-Pin Plastic DIP (derate 10.0mW/°C above +70°C) ....800mW

14-Pin SO (derate 8.33mW/°C above +70°C)..............667mW

Operating Temperature Ranges

MAX308_C_ _ .....................................................0°C to +70°C

MAX308_E_ _...................................................-40°C to +85°C

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

Lead Temperature (soldering, 10sec) .............................+300°C

CC

(H/F, SRL, TXP, RXP)..................................-0.3V to (V + 0.3V)

CC

Driver Input Voltage (DI).............................-0.3V to (V + 0.3V)

CC

Driver Output Voltage (A, B, Y, Z)........................................±13V

Receiver Input Voltage (A, B) ..............................................±13V

Receiver Input Voltage, Full Duplex (A, B) ..........................±25V

Receiver Output Voltage (RO)....................-0.3V to (V + 0.3V)

CC

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.

DC ELECTRICAL CHARACTERISTICS

(V = +5V ± 5%, T = T

to T , unless otherwise noted. Typical values are at V = +5V and T = +25°C.) (Note 1)

MAX CC A

CC

A

MIN

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

–MAX3089

DRIVER

Differential Driver Output

(no load)

V

Figure 5

5

V

OD1

Figure 5, R = 50Ω (RS-422)

Figure 5, R = 27Ω (RS-485)

2.0

1.5

Differential Driver Output

V

OD2

Change in Magnitude of

Differential Output Voltage

(Note 2)

∆V

Figure 5, R = 50Ω or R = 27Ω

0.2

V

OD

Driver Common-Mode Output

Voltage

V

Figure 5, R = 50Ω or R = 27Ω

3

V

OC

Change In Magnitude of

Common-Mode Voltage (Note 2)

∆V

0.2

OC

Input High Voltage

Input Low Voltage

V

2.0

10

V

DE, DI, RE, H/F, TXP, RXP

IH1

V

IL1

0.8

MAX3080–MAX3085, and MAX3089 with

SRL = V or unconnected

CC

DI Input Hysteresis

SRL Input Current

V

HYS

100

mV

µA

I

IN1

±2

40

DE, DI, RE

I

IN2

H/F, TXP, RXP, internal pull-down

Input High Voltage

Input Middle Voltage

Input Low Voltage

V

SRL

V

- 0.8

V

IH2

CC

V

IM2

SRL (Note 3)

SRL

0.4V

0.6V

CC

V

IL2

0.8

75

SRL = V

CC

SRL Input Current

I

IN3

µA

SRL = GND (Note 3)

-75

V

= 12V

= -7V

= 12V

= -7V

125

-75

IN

Input Current (A and B)

Full Duplex

DE = GND,

V

CC

I

IN4

= GND or 5.25V

V

IN

V

IN

125

Output Leakage (Y and Z)

Full Duplex

DE = GND,

= GND or 5.25V

I

O

V

CC

V

IN

-100

-250

-7V ≤ V

≤ V

CC

OUT

Driver Short-Circuit Output

Current (Note 4)

V

OD1

250

mA

0V ≤ V

≤ 12V

OUT

±25

0V ≤ V

≤ V

CC

OUT

2

_______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

DC ELECTRICAL CHARACTERISTICS (continued)

(V = +5V ±5%, T = T

to T

, unless otherwise noted. Typical values are at V = +5V and T = +25°C.) (Note 1)

CC

A

MIN

MAX

CC

A

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

RECEIVER

Receiver Differential Threshold

Voltage

Receiver Input Hysteresis

V

-7V ≤ V ≤ 12V

-200

-125

25

-50

mV

TH

CM

∆V

mV

V

TH

Receiver Output High Voltage

Receiver Output Low Voltage

V

OH

I

O

= -4mA, V = -50mV

V

-1.5

ID

CC

V

OL

I

O

= 4mA, V = -200mV

0.4

±1

V

ID

Three-State Output Current at

Receiver

I

0.4V ≤ V ≤ 2.4V

µA

kΩ

OZR

O

Receiver Input Resistance

R

-7V ≤ V ≤ 12V

96

±7

IN

CM

Receiver Output Short-Circuit

Current

I

0V ≤ V ≤ V

CC

±95

mA

OSR

RO

SUPPLY CURRENT

No load,

RE = DI = GND

DE = V

430

375

475

420

900

600

CC

µA

DE = GND

DE = V

or V , SRL = V

CC

Supply Current

I

CC

No load,

RE = DI = GND

1000

800

CC

µA

DE = GND

or V , SRL = GND

CC

Supply Current in Shutdown

Mode

I

DE = GND, V = V

CC

0.001

10

SHDN

RE

Note 1: All currents into the device are positive; all currents out of the device are negative. All voltages are referred to device

ground unless otherwise noted.

Note 2: ∆V and ∆V are the changes in V and V , respectively, when the DI input changes state.

OD

OC

OD

OC

Note 3: The SRL pin is internally biased to V / 2 by a 100kΩ/100kΩ resistor divider. It is guaranteed to be V / 2 if left

CC

unconnected.

Note 4: Maximum current level applies to peak current just prior to foldback-current limiting; minimum current level applies during

current limiting.

_______________________________________________________________________________________

3

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

SWITCHING CHARACTERISTICS—MAX3080–MAX3082, and MAX3089 with

SRL = Unconnected

(V = +5V ±5%, T = T

to T , unless otherwise noted. Typical values are at V = +5V and T = +25°C.)

MAX CC A

CC

A

MIN

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

2030

MAX

2600

UNITS

t

500

DPLH

DPHL

Figures 7 and 9, R

= 54Ω,

DIFF

Driver Input to Output

ns

C

= C = 100pF

L2

L1

Driver Output Skew

Figures 7 and 9, R

DIFF

t

-3

±200

2500

ns

DSKEW

C

= C = 100pF

L2

t

- t

L1

| DPLH DPHL |

Figures 7 and 9, R

DIFF

Driver Rise or Fall Time

t

, t

DR DF

667

115

1320

C

= C = 100pF

L2

L1

Maximum Data Rate

f

kbps

ns

MAX

Driver Enable to Output High

Driver Enable to Output Low

Driver Disable Time from Low

Driver Disable Time from High

t

Figures 8 and 10, C = 100pF, S2 closed

3500

100

DZH

L

t

Figures 8 and 10, C = 100pF, S1 closed

ns

DZL

DLZ

DHZ

L

t

Figures 8 and 10, C = 15pF, S1 closed

ns

L

t

Figures 8 and 10, C = 15pF, S2 closed

100

ns

L

–MAX3089

t

,

Figures 11 and 13;

rise and fall time of V ≤ 15ns

V

≥ 2.0V;

RPLH

|

ID |

Receiver Input to Output

127

3

200

±30

ns

RPHL

ID

t

- t

Differential

Figures 11 and 13;

rise and fall time of V ≤ 15ns

V

ID |

ID

≥ 2.0V;

| RPLH RPHL |

Receiver Skew

|

t

RSKD

Receiver Enable to Output Low

t

Figures 6 and 12, C = 100pF, S1 closed

20

50

ns

RZL

L

Receiver Enable to Output High

Receiver Disable Time from Low

t

Figures 6 and 12, C = 100pF, S2 closed

L

RZH

t

Figures 6 and 12, C = 100pF, S1 closed

L

RLZ

Receiver Disable Time from

High

t

Figures 6 and 12, C = 100pF, S2 closed

L

20

50

ns

RHZ

Time to Shutdown

t

(Note 5)

50

200

600

SHDN

Driver Enable from Shutdown to

Output High

t

Figures 8 and 10, C = 15pF, S2 closed

6000

DZH(SHDN)

L

Driver Enable from Shutdown to

Output Low

t

Figures 8 and 10, C = 15pF, S1 closed

6000

3500

ns

DZL(SHDN)

L

Receiver Enable from Shutdown

to Output High

Figures 6 and 12, C = 100pF, S2 closed

RZH(SHDN)

L

Receiver Enable from Shutdown

to Output Low

t

Figures 6 and 12, C = 100pF, S1 closed

L

RZL(SHDN)

4

_______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

SWITCHING CHARACTERISTICS—MAX3083–MAX3085, and MAX3089 with SRL = V

CC

(V = +5V ±5%, T = T

to T , unless otherwise noted. Typical values are at V = +5V and T = +25°C.)

MAX CC A

CC

A

MIN

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

720

MAX

1000

UNITS

t

250

DPLH

DPHL

Figures 7 and 9, R

= 54Ω,

DIFF

Driver Input to Output

ns

C

= C = 100pF

L2

L1

Driver Output Skew

Figures 7 and 9, R

DIFF

t

-3

±100

750

ns

DSKEW

C

= C = 100pF

L2

t

- t

L1

| DPLH DPHL |

Figures 7 and 9, R

DIFF

Driver Rise or Fall Time

t

200

500

530

DR, DF

C

= C = 100pF

L2

L1

Maximum Data Rate

f

kbps

ns

MAX

Driver Enable to Output High

Driver Enable to Output Low

Driver Disable Time from Low

Driver Disable Time from High

t

Figures 8 and 10, C = 100pF, S2 closed

2500

100

DZH

L

t

Figures 8 and 10, C = 100pF, S1 closed

ns

DZL

DLZ

DHZ

L

t

Figures 8 and 10, C = 15pF, S1 closed

ns

L

t

Figures 8 and 10, C = 15pF, S2 closed

100

ns

L

t

,

Figures 11 and 13;

rise and fall time of V ≤ 15ns

V

≥ 2.0V;

ID

|

RPLH

|

Receiver Input to Output

127

3

200

±30

ns

RPHL

ID

t

- t

Differential

Figures 11 and 13;

rise and fall time of V ≤ 15ns

ID

V ≥ 2.0V;

ID

|

RPLH RPHL

|

t

RSKD

Receiver Skew

Receiver Enable to Output Low

t

Figures 6 and 12, C = 100pF, S1 closed

20

50

ns

RZL

L

Receiver Enable to Output High

Receiver Disable Time from Low

t

Figures 6 and 12, C = 100pF, S2 closed

L

RZH

t

Figures 6 and 12, C = 100pF, S1 closed

L

RLZ

Receiver Disable Time from

High

t

Figures 6 and 12, C = 100pF, S2 closed

L

20

50

ns

RHZ

Time to Shutdown

t

(Note 5)

50

200

600

ns

SHDN

Driver Enable from Shutdown to

Output High

t

Figures 8 and 10, C = 15pF, S2 closed

4500

DZH(SHDN)

L

Driver Enable from Shutdown to

Output Low

t

Figures 8 and 10, C = 15pF, S1 closed

4500

ns

DZL(SHDN)

L

Receiver Enable from Shutdown

to Output High

Figures 6 and 12, C = 100pF, S2 closed

3500

ns

RZH(SHDN)

L

Receiver Enable from Shutdown

to Output Low

t

Figures 6 and 12, C = 100pF, S1 closed

L

RZL(SHDN)

_______________________________________________________________________________________

5

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

SWITCHING CHARACTERISTICS—MAX3086–MAX3088, and MAX3089 with SRL = GND

(V = +5V ±5%, T = T

to T , unless otherwise noted. Typical values are at V = +5V and T = +25°C.)

MAX CC A

CC

A

MIN

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

34

MAX

60

UNITS

t

DPLH

DPHL

Figures 7 and 9, R

= 54Ω,

DIFF

Driver Input to Output

ns

C

= C = 100pF

L2

L1

34

60

Driver Output Skew

Figures 7 and 9, R

DIFF

t

-2.5

14

±10

25

ns

DSKEW

C

= C = 100pF

L2

t

- t

L1

| DPLH DPHL |

Figures 7 and 9, R

DIFF

Driver Rise or Fall Time

t

DR, DF

C

= C = 100pF

L2

L1

Maximum Data Rate

f

10

Mbps

ns

MAX

Driver Enable to Output High

Driver Enable to Output Low

Driver Disable Time from Low

Driver Disable Time from High

t

Figures 8 and 10, C = 100pF, S2 closed

150

100

DZH

L

t

Figures 8 and 10, C = 100pF, S1 closed

ns

DZL

DLZ

DHZ

L

t

Figures 8 and 10, C = 15pF, S1 closed

ns

L

t

Figures 8 and 10, C = 15pF, S2 closed

ns

L

t

,

Figures 11 and 13;

rise and fall time of V ≤ 15ns

V

≥ 2.0V;

RPLH

|

ID |

Receiver Input to Output

106

0

150

±10

ns

–MAX3089

RPHL

ID

t

- t

Differential

Figures 11 and 13;

rise and fall time of V ≤ 15ns

V

ID |

ID

≥ 2.0V;

| RPLH RPHL |

Receiver Skew

|

t

RSKD

Receiver Enable to Output Low

t

Figures 6 and 12, C = 100pF, S1 closed

20

50

ns

RZL

L

Receiver Enable to Output High

Receiver Disable Time from Low

t

Figures 6 and 12, C = 100pF, S2 closed

L

RZH

t

Figures 6 and 12, C = 100pF, S1 closed

L

RLZ

Receiver Disable Time from

High

t

Figures 6 and 12, C = 100pF, S2 closed

L

20

50

ns

RHZ

Time to Shutdown

t

(Note 5)

50

200

600

250

ns

SHDN

Driver Enable from Shutdown to

Output High

t

Figures 8 and 10, C = 15pF, S2 closed

L

DZH(SHDN)

Driver Enable from Shutdown to

Output Low

t

Figures 8 and 10, C = 15pF, S1 closed

250

ns

DZL(SHDN)

L

Receiver Enable from Shutdown

to Output High

Figures 6 and 12, C = 100pF, S2 closed

3500

ns

RZH(SHDN)

L

Receiver Enable from Shutdown

to Output Low

t

Figures 6 and 12, C = 100pF, S1 closed

L

RZL(SHDN)

Note 5: The device is put into shutdown by bringing RE high and DE low. If the enable inputs are in this state for less than 50ns, the

device is guaranteed not to enter shutdown. If the enable inputs are in this state for at least 600ns, the device is guaranteed

to have entered shutdown.

6

_______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s

(V = +5V, T = +25°C, unless otherwise noted.)

CC

A

NO-LOAD SUPPLY CURRENT

vs. TEMPERATURE

OUTPUT CURRENT

vs. RECEIVER OUTPUT LOW VOLTAGE

OUTPUT CURRENT

vs. RECEIVER OUTPUT HIGH VOLTAGE

525

60

50

40

30

20

10

0

30

25

20

15

10

5

A: MAX3086–MAX3088,

MAX3089 WITH

SRL = GND

500

475

DE = V

CC

450

425

400

375

350

A

DE = GND

B

A

B: MAX3080–MAX3085,

MAX3089 WITH

B

325

300

SRL = OPEN OR V

CC

0

-60 -40 -20

0

20 40 60 80 100

0

1

2

3

4

5

0

1

2

3

4

5

TEMPERATURE (°C)

OUTPUT LOW VOLTAGE (V)

OUTPUT HIGH VOLTAGE (V)

SHUTDOWN CURRENT

vs. TEMPERATURE

RECEIVER OUTPUT HIGH VOLTAGE

vs. TEMPERATURE

RECEIVER OUTPUT LOW VOLTAGE

vs. TEMPERATURE

20

18

4.5

4.4

4.3

0.50

0.45

0.40

I

RO

= 8mA

I

RO

= 8mA

16

14

12

0.35

0.30

0.25

4.2

4.1

10

8

6

4

2

4.0

3.9

3.8

0.20

0.15

0.10

0

-60 -40 -20

0

20 40 60 80 100

-60 -40 -20

0

20 40 60 80 100

-60 -40 -20

0

20 40 60 80 100

TEMPERATURE (°C)

RECEIVER PROPAGATION DELAY

(500kbps MODE) vs. TEMPERATURE

RECEIVER PROPAGATION DELAY

(10Mbps MODE) vs. TEMPERATURE

DRIVER PROPAGATION DELAY

(115kbps MODE) vs. TEMPERATURE

140

112

2.20

2.15

2.10

2.05

2.00

1.95

C

LOAD

= 100pF

C

LOAD

= 100pF

R = 54Ω

t

110

108

135

130

106

104

102

100

98

125

120

115

96

94

1.90

-60 -40 -20

0

20 40 60 80 100

-60 -40 -20

0

20 40 60 80 100

-60 -40 -20

0

20 40 60 80 100

TEMPERATURE (°C)

_______________________________________________________________________________________

7

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s (c o n t in u e d )

(V = +5V, T = +25°C, unless otherwise noted.)

CC

A

DRIVER DIFFERENTIAL OUTPUT VOLTAGE

vs. TEMPERATURE

DRIVER PROPAGATION DELAY

(500kbps MODE) vs. TEMPERATURE

DRIVER PROPAGATION DELAY

(10Mbps MODE) vs. TEMPERATURE

1.90

1.89

920

880

840

800

760

720

680

640

600

560

520

60

55

50

45

R = 54Ω

t

R = 54Ω

t

1.88

1.87

1.86

1.85

1.84

1.83

40

35

30

25

20

-60 -40 -20

0

20 40 60 80 100

-60 -40 -20

0

20 40 60 80 100

-60 -40 -20

0

20 40 60 80 100

–MAX3089

TEMPERATURE (°C)

DRIVER OUTPUT CURRENT

OUTPUT CURRENT vs.

vs. DIFFERENTIAL OUTPUT VOLTAGE

DRIVER OUTPUT HIGH VOLTAGE

DRIVER OUTPUT LOW VOLTAGE

100

-100

-90

-80

-70

140

120

10

1

100

-60

-50

80

60

-40

-30

40

20

0

0.1

-20

-10

0

0.01

0

1

2

3

4

5

-8

-6

-4

-2

0

2

4

6

0

2

4

6

8

10

12

DIFFERENTIAL OUTPUT VOLTAGE (V)

OUTPUT HIGH VOLTAGE (V)

OUTPUT LOW VOLTAGE (V)

8

_______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s (c o n t in u e d )

(V = +5V, T = +25°C, unless otherwise noted.)

CC

A

RECEIVER PROPAGATION DELAY

MAX3080–MAX3085, AND MAX3089

RECEIVER PROPAGATION DELAY

MAX3086–MAX3088, AND MAX3089

WITH SRL = GND

WITH SRL = OPEN OR V

CC

MAX3080/3089 TYP-17

MAX3080/3089 TYP-18

V - V

2V/div

5V/div

A

B

V - V

2V/div

5V/div

A

B

RO

50ns/div

DRIVER PROPAGATION DELAY

MAX3080/MAX3081/MAX3082, AND MAX3089

WITH SRL = OPEN

MAX3080/3089 TYP-20

DI

5V/div

V - V

2.5V/div

Y

Z

2µs/div

DRIVER PROPAGATION DELAY

MAX3083/MAX3084/MAX3085, AND MAX3089

WITH SRL = V

MAX3086/MAX3087/MAX3088, AND MAX3089

WITH SRL = GND

CC

MAX3080/3089 TYP-21

MAX3080/3089 TYP-22

DI

5V/div

DI

5V/div

V - V

2.5V/div

V - V

Y Z

2.5V/div

Y

Z

500ns/div

50ns/div

_______________________________________________________________________________________

9

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

P in De s c rip t io n

MAX3080 MAX3081 MAX3082

MAX3083 MAX3084 MAX3085

MAX3086 MAX3087 MAX3088

MAX3089

NAME

FUNCTION

HALF-

FULL-

HALF-

FULL-DUPLEX

DUPLEX DUPLEX DUPLEX

DEVICES

MODE

Half/Full-Duplex Selector Pin. Connect H/F to V for half-duplex

mode; connect to GND or leave unconnected for full-duplex mode.

CC

—

2

—

1

H/F

Receiver Output. When RE is low and if A - B ≥ -50mV, RO will be

high; if A - B ≤ -200mV, RO will be low.

2

3

1

2

3

2

3

RO

Receiver Output Enable. Drive RE low to enable RO; RO is high

impedance when RE is high. Drive RE high and DE low to enter

low-power shutdown mode.

—

3

RE

DE

DI

–MAX3089

Driver Output Enable. Drive DE high to enable driver outputs. These

outputs are high impedance when DE is low. Drive RE high and DE

low to enter low-power shutdown mode.

4

5

3

4

5

4

5

Driver Input. With DE high, a low on DI forces noninverting output

low and inverting output high. Similarly, a high on DI forces non-

inverting output high and inverting output low.

Slew-Rate-Limit Selector Pin. Connect SRL to GND for 10Mbps

—

6, 7

—

4

—

5

6

7

8

6

7

8

SRL communication rate; connect to V for 500kbps communication

CC

rate. Leave unconnected for 115kbps communication rate.

GND Ground

Transmitter Phase. Connect TXP to GND, or leave floating for normal

TXP transmitter phase/polarity. Connect to V to invert the transmitter

CC

—

phase/polarity.

9

5

—

7

9

—

9

Y

Z

B

Noninverting Driver Output

—

10

—

11

—

6

—

10

—

11

—

Noninverting Receiver Input and Noninverting Driver Output*

Inverting Driver Output

—

10

—

11

—

7

Inverting Receiver Input and Inverting Driver Output*

Inverting Receiver Input

—

Receiver Input Resistors*

Inverting Receiver Input and Inverting Driver Output

10 ______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

P in De s c rip t io n (c o n t in u e d )

MAX3080 MAX3081 MAX3082

MAX3083 MAX3084 MAX3085

MAX3086 MAX3087 MAX3088

MAX3089

NAME

FUNCTION

HALF-

FULL-

DUPLEX DUPLEX

MODE

12

HALF-

FULL-DUPLEX

DUPLEX

DEVICES

MODE

—

12

—

8

—

6

A

Noninverting Receiver Input

Receiver Input Resistors*

—

12

—

Noninverting Receiver Input and Noninverting Driver Output

Receiver Phase. Connect RXP to GND, or leave unconnected for

—

13

RXP normal transmitter phase/polarity. Connect to V to invert the

CC

receiver phase/polarity.

14

1

8

14

—

14

—

V

Positive Supply; 4.75V ≤ V ≤ 5.25V

CC

1, 8, 13

—

N.C. Not Connected. Not internally connected.

*(MAX3089 only.) In half-duplex mode, the driver outputs serve as receiver inputs. The full-duplex receiver inputs (A and B) will still

have a 1/8-unit load, but are not connected to the receiver.

Fu n c t io n Ta b le s

MAX3080/MAX3083/MAX3086

MAX3081/MAX3084/MAX3087

TRANSMITTING

OUTPUTS

TRANSMITTING

INPUT

INPUTS

OUTPUTS

DI

1

Z

0

1

Y

1

DE

1

DI

1

Z

0

1

Y

RE

X

0

1

0

1

0

X

High-Z

1

0

Shutdown

RECEIVING

INPUTS

OUTPUT

A-B

≥ -0.05V

RO

1

RECEIVING

INPUTS

OUTPUT

≤ -0.2V

0

DE

X

1

A-B

RO

RE

Open/shorted

1

0

1

≥ -0.05V

1

≤ -0.2V

0

1

Open/shorted

X

High-Z

Shutdown

0

X = Don’t care

Shutdown mode, driver and receiver outputs high impedance

______________________________________________________________________________________ 11

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

Fu n c t io n Ta b le s (c o n t in u e d )

MAX3082/MAX3085/MAX3088

MAX3089

TRANSMITTING

INPUTS

DE

TRANSMITTING

OUTPUTS

INPUTS

OUTPUTS

TXP

0

DI

1

Z

Y

RE

X

0

DE

1

DI

1

B/Z

A/Y

RE

X

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

X

High-Z

1

0

1

0

Shutdown

X

High-Z

1

Shutdown

RECEIVING

INPUTS

OUTPUT

DE

X

1

A-B

RO

RE

RECEIVING

INPUTS

0

1

≥ -0.05V

1

OUTPUT

–MAX3089

≤ -0.2V

0

1

RXP

0

DE

X

0

A-B

≥ -0.05V

≤ -0.2V

≥ -0.05V

≤ -0.2V

X

Y-Z

X

RO

1

H/F

0

RE

Open/shorted

0

X

High-Z

Shutdown

0

X

0

1

X

0

1

X

1

0

≥ -0.05V

≤ -0.2V

≥ -0.05V

≤ -0.2V

1

0

X

0

1

0

X

0

1

0

X

1

Open/

shorted

0

1

0

1

0

1

0

X

0

X

1

0

Open/

shorted

X

Open/

shorted

X

0

X

Open/

shorted

X

1

0

X

High-Z

Shutdown

X = Don’t care

Shutdown mode, driver and receiver outputs high impedance

12 ______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

V

CC

DE

V

CC

RE

TOP VIEW

0.1µF

4

14

MAX3080

MAX3083

MAX3086

N.C.

RO

RE

DE

DI

1

2

3

4

5

6

7

14

V

CC

9

Y

R

13 N.C.

5

Rt

DI

RO

DI

D

R

10

12

11

10

9

A

Z

B

12

11

A

2

Rt

Z

RO

NC

R

D

GND

Y

B

1, 8, 13

8

N.C.

3

6, 7

GND

DIP/SO

RE

GND DE

Figure 1. MAX3080/MAX3083/MAX3086 Pin Configuration and Typical Full-Duplex Operating Circuit

TOP VIEW

0.1µF

V

CC

TOP VIEW

MAX3081

MAX3084

MAX3087

V

CC

1

Y

5

3

2

Rt

DI

RO

D

R

V

1

2

3

4

R

8

7

6

5

A

B

Z

CC

6 Z

RO

DI

8

7

A

Rt

RO

DI

R

D

GND

Y

D

B

DIP/SO

4

GND

Figure 2. MAX3081/MAX3084/MAX3087 Pin Configuration and Typical Full-Duplex Operating Circuit

TOP VIEW

0.1µF

MAX3082

MAX3085

MAX3088

DE

D

DI

R

1

2

3

4

RO

RE

DE

DI

1

2

3

4

RO

RE

DE

DI

8

7

6

5

V

CC

B

Rt

V

CC

B

A

7

B

Rt

6

A

RO

R

D

5

GND

RE

NOTE: PIN LABELS Y AND Z ON TIMING, TEST, AND WAVEFORM DIAGRAMS REFER TO PINS A AND B WHEN DE IS HIGH.

DIP/SO

Figure 3. MAX3082/MAX3085/MAX3088 Pin Configuration and Typical Half-Duplex Operating Circuit

______________________________________________________________________________________ 13

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

The MAX3082/MAX3085/MAX3088 a re ha lf-d up le x

De t a ile d De s c rip t io n

transceivers, while the MAX3080/MAX3081/MAX3083/

The MAX3080–MAX3089 high-speed transceivers for

MAX3084/MAX3086/MAX3087 are full-duplex trans-

RS-485/RS-422 communication contain one driver and

ceivers. The MAX3089 is selectable between half- and

one receiver. These devices feature fail-safe circuitry,

full-duplex communication by driving a selector pin

which guarantees a logic-high receiver output when the

high or low, respectively.

receiver inputs are open or shorted, or when they are

All of these parts operate from a single +5V supply.

Drivers are output short-circuit current limited. Thermal

shutdown circuitry protects drivers against excessive

power dissipation. When activated, the thermal shut-

down circuitry places the driver outputs into a high-

impedance state.

connected to a terminated transmission line with all

drivers disabled (see Fail-Safe section). The MAX3080/

MAX3081/MAX3082 feature reduced slew-rate drivers

that minimize EMI and reduce reflections caused by

improperly terminated cables, allowing error-free data

transmission up to 115kbps (see Reduced EMI and

Reflections section). The MAX3083/MAX3084/MAX3085

offe r hig he r d rive r outp ut s le w-ra te limits , a llowing

tra ns mit s p e e d s up to 500kb p s . The MAX3086/

MAX3087/MAX3088’s driver slew rates are not limited,

making transmit speeds up to 10Mbps possible. The

MAX3089’s slew rate is selectable between 115kbps,

500kbps, and 10Mbps by driving a selector pin with a

three-state driver.

Re c e ive r In p u t Filt e rin g

The re c e ive rs of the MAX3080–MAX3085, a nd the

MAX3089 whe n op e ra ting in 115kb p s or 500kb p s

mode, incorporate input filtering in addition to input

hysteresis. This filtering enhances noise immunity with

differential signals that have very slow rise and fall

times. Receiver propagation delay increases by 20%

due to this filtering.

–MAX3089

V

CC

RE

MAX3089

A

RD

TOP VIEW

B

H/F

RO

1

2

3

4

5

6

7

14

V

CC

13 RXP

RE

12

11

10

9

A

MAX3089

DE

B

H/F

TXP

Z

DI

Z

SRL

GND

Y

8

TXP

DIP/SO

Y

DI

NOTE: SWITCH POSITIONS

INDICATED FOR H/F = GND

GND DE

SRL

Figure 4. MAX3089 Pin Configuration and Functional Diagram

14 ______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

Y

1k

TEST POINT

R

RECEIVER

OUTPUT

V

CC

S1

S2

C

RL

V

OD

1k

15pF

V

OC

Z

Figure 5. Driver DC Test Load

Figure 6. Receiver Enable/Disable Timing Test Load

TXP and RXP low, connect them to ground, or leave

them unconnected (internal pull-down). To invert the

Fa il-S a fe

The MAX3080 family guarantees a logic-high receiver

output when the receiver inputs are shorted or open, or

when they are connected to a terminated transmission

line with all drivers disabled. This is done by setting the

receiver threshold between -50mV and -200mV. If the

differential receiver input voltage (A-B) is greater than

or equal to -50mV, RO is logic high. If A-B is less than

or equal to -200mV, RO is logic low. In the case of a

te rmina te d b us with a ll tra ns mitte rs d is a b le d , the

receiver’s differential input voltage is pulled to 0V by

the termination. With the receiver thresholds of the

MAX3080 family, this results in a logic high with a 50mV

minimum nois e ma rg in. Unlike p re vious fa il-s a fe

devices, the -50mV to -200mV threshold complies with

the ±200mV EIA/TIA-485 standard.

driver phase, drive TXP high or connect it to V . To

CC

invert the receiver phase, drive RXP high or connect it

to V . Note that the receiver threshold is positive

CC

when RXP is high.

The MAX3089 can operate in full- or half-duplex mode.

Drive the H/F pin low, leave it unconnected (internal

pull-down), or connect it to GND for full-duplex opera-

tion, and drive it high for half-duplex operation. In full-

duplex mode, the pin configuration of the driver and

receiver is the same as that of a MAX3080 (Figure 4). In

half-duplex mode, the receiver inputs are switched to

the driver outputs, connecting outputs Y and Z to inputs

A and B, respectively. In half-duplex mode, the internal

full-duplex receiver input resistors are still connected to

pins 11 and 12.

MAX3 0 8 9 P ro g ra m m in g

The MAX3089 has several programmable operating

modes. Transmitter rise and fall times are programma-

ble between 2500ns, 750ns, and 25ns, resulting in

ma ximum d a ta ra te s of 115kb p s , 500kb p s , a nd

10Mbps, respectively. To select the desired data rate,

drive SRL to one of three possible states by using a

Ap p lic a t io n s In fo rm a t io n

2 5 6 Tra n s c e ive rs o n t h e Bu s

The standard RS-485 receiver input impedance is 12kΩ

(one-unit load), and the standard driver can drive up to

32 unit loads. The MAX3080 family of transceivers have

a 1/8-unit-load receiver input impedance (96kΩ), allow-

ing up to 256 transceivers to be connected in parallel

on one communication line. Any combination of these

devices and/or other RS-485 transceivers with a total of

32 unit loads or less can be connected to the line.

three-state driver, by connecting it to V

or GND, or

CC

by leaving it unconnected. For 115kbps operation, set

the thre e -s ta te d e vic e in hig h-imp e d a nc e mod e or

leave SRL unconnected. For 500kbps operation, drive

SRL high or connect it to V . For 10Mbps operation,

CC

d rive SRL low or c onne c t it to GND. SRL c a n b e

changed during operation without interrupting data

communications.

Re d u c e d EMI a n d Re fle c t io n s

The MAX3080–MAX3085, and MAX3089 with SRL = V

CC

or unconnected, are slew-rate limited, minimizing EMI

and reducing reflections caused by improperly termi-

nated cables. Figure 14 shows the driver output wave-

form a nd its Fourie r a na lys is of a 20kHz s ig na l

transmitted by a MAX3086/MAX3087/MAX3088, and

MAX3089 with SRL = GND. High-frequency harmonic

Occasionally, twisted-pair lines are connected back-

ward from normal orientation. The MAX3089 has two

pins that invert the phase of the driver and the receiver

to correct for this problem. For normal operation, drive

______________________________________________________________________________________ 15

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

3V

DE

C

L1

V

CC

Y

Z

S1

S2

500Ω

R

DIFF

DI

OUTPUT

UNDER TEST

V

ID

C

L

C

L2

Figure 7. Driver Timing Test Circuit

Figure 8. Driver Enable/Disable Timing Test Load

–MAX3089

3V

DE

DI

1.5V

V

0V

t

PHL

PLH

1/2 V

O

t

, t

LZ

ZL(SHDN) ZL

Z

Y, Z

2.3V

V

+0.5V

-0.5V

O

OUTPUT NORMALLY LOW

OUTPUT NORMALLY HIGH

OL

V

OL

Y

1/2 V

O

V

DIFF

= V (Y) - V (Z)

Y, Z

0V

V

O

V

OH

2.3V

V

DIFF

90%

0V

-V

10%

O

t

, t

t

HZ

ZH(SHDN) ZH

t

R

t

F

t

- t

SKEW = | PLH PHL |

Figure 9. Driver Propagation Delays

Figure 10. Driver Enable and Disable Times (except

MAX3081/MAX3084/MAX3087)

3V

RE

1.5V

0V

V

OH

RO

1.5V

V

OL

OUTPUT

t

LZ

t

, t

ZL(SHDN) ZL

V

RO

CC

t

PLH

PHL

A

B

1V

1.5V

V

+ 0.5V

- 0.5V

OUTPUT NORMALLY LOW

OUTPUT NORMALLY HIGH

OL

-1V

INPUT

RO

V

OH

1.5V

0V

t

, t

t

HZ

ZH(SHDN) ZH

Figure 11. Receiver Propagation Delays

Figure 12. Receiver Enable and Disable Times (except

MAX3081/MAX3084/MAX3087)

16 ______________________________________________________________________________________

Fa il-S a fe , Hig h -S p e e d (1 0 Mb p s ),

S le w -Ra t e -Lim it e d RS -4 8 5 /RS -4 2 2 Tra n s c e ive rs

–MAX3089

B

RECEIVER

OUTPUT

V

ID

R

20dB/div

ATE

A

0Hz

100kHz/div

1MHz

Figure 13. Receiver Propagation Delay Test Circuit

Figure 14. Driver Output Waveform and FFT Plot of

MAX3086/MAX3087/MAX3088, and MAX3089 with

SRL = GND, Transmitting a 20kHz Signal

A

B

20dB/div

0Hz

100kHz/div

1MHz

0Hz

100kHz/div

1MHz

Figure 15. Driver Output Waveform and FFT Plot of

MAX3083/MAX3084/MAX3085, and MAX3089

Figure 16. Driver Output Waveform and FFT Plot of

MAX3080/MAX3081/MAX3082, and MAX3089

with SRL = V

Transmitting a 20kHz Signal

with SRL = Unconnected, Transmitting a 20kHz Signal

CC,

components with large amplitudes are evident. Figure

15 shows the same signal displayed for a MAX3083/

MAX3084/MAX3085, and MAX3089 with SRL = VCC),

transmitting under the same conditions. Fig

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