MAXIM MAX1480E, MAX1490E User Manual

_________________General Description

The MAX1480EA/MAX1480EC/MAX1490EA/MAX1490EB
are complete, electrically isolated, RS-485/RS-422 data
communications interface solutions in a hybrid microcir­cuit. The RS-485/RS-422 I/O pins are protected against
±15kV electrostatic discharge (ESD) shocks, without
latchup. Transceivers, optocouplers, and a transformer
provide a complete interface in a standard DIP package.
A single +5V supply on the logic side powers both sides
of the interface.

The MAX1480EC/MAX1490EB feature reduced-slew-rate
drivers that minimize EMI and reduce reflections caused
by improperly terminated cables, allowing error-free data
transmission at data rates up to 160kbps. The
MAX1480EA/MAX1490EA driver slew rate is not limited,
allowing transmission rates up to 2.5Mbps. The
MAX1480EA/MAX1480EC are designed for half-duplex
communication, while the MAX1490EA/MAX1490EB fea­ture full-duplex communication.

Drivers are short-circuit current limited and protected
against excessive power dissipation by thermal shut­down circuitry that places the driver outputs into a high­impedance state. The receiver input has a fail-safe
feature that guarantees a known output (RO low for the
MAX1480EA/MAX1480EC, RO high for the MAX1490EA/
MAX1490EB) if the input is open circuit.

The MAX1480EA/MAX1480EC/MAX1490EA/MAX1490EB
withstand 1260V

RMS

(1min) or 1520V

RMS

(1s). Their iso­lated outputs meet all RS-485/RS-422 specifications. The
MAX1480EA/MAX1480EC are available in a 28-pin DIP
package, and the MAX1490EA/MAX1490EB are available
in a 24-pin DIP package.

.

________________________Applications

Isolated RS-485/RS-422 Data Interface
Transceivers for EMI-Sensitive Applications
Industrial-Control Local Area Networks
Automatic Test Equipment
HVAC/Building Control Networks
Telecom

____________________________Features

♦ Isolated Data Interface, Guaranteed to 1260V

RMS

(1min)

♦ ±15kV ESD Protection on I/O Pins
♦ Slew-Rate Limited for Errorless Data

Transmission (MAX1480EC/MAX1490EB)

♦ High-Speed, Isolated, 2.5Mbps RS-485/RS-422

Interface (MAX1480EA/MAX1490EA)

♦ Full-Duplex Data Communication

(MAX1490EA/MAX1490EB)

♦ Single +5V Supply
♦ Current Limiting and Thermal Shutdown for

Driver Overload Protection

♦ Standard 0.6in DIP Packages

28-Pin DIP (MAX1480EA/MAX1480EC)
24-Pin DIP (MAX1490EA/MAX1490EB)

MAX1480E/MAX1490E

±15kV ESD-Protected, Isolated RS-485/RS-422

Data Interfaces

________________________________________________________________ Maxim Integrated Products 1

Pin Configurations

1

24

23

22

21

20

19

18

17

2

3

4

5

6

7

8

AC1

AC2

ISO V

CC1

ISO RO DRVD2

D1

A

B

Z

Y

SD

FS

GND1

16

15

14

13

9

10

11

12

ISO COM1

ISO DI DRV

ISO V

CC2

ISO RO LED

GND2

RO

DI

DIP

V

CC2

V

CC3

V

CC4

V

CC1

MAX1490EA/

MAX1490EB

MAX845E

MAX488E

MAX490E

TOP VIEW

ISOLATION BARRIER

19-1940; Rev 0; 4/01

PART

†

MAX1480EACPI

MAX1480EAEPI -40°C to +85°C

0°C to +70°C

TEMP. RANGE PIN-PACKAGE

28 Wide Plastic DIP*

28 Wide Plastic DIP*

_______________Ordering Information

Ordering Information continued at end of data sheet.

†

Data rate for A parts is up to 2.5Mbps. Data rate for C parts is

up to 250kbps.
*See Reliability section at end of data sheet.

Pin Configurations continued at end of data sheet.

Selector Guide appears at end of data sheet.

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.

mA

MAX1480E/MAX1490E

±15kV ESD-Protected, Isolated RS-485/RS-422
Data Interfaces

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V

CC_

= +5V ±10%, VFS= V

CC_

, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at V

CC_

= +5V and TA= +25°C.)

(Notes 1, 2)

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.

With Respect to GND_

Supply Voltage (V

CC_

)..........................................-0.3V to +6V

Control Input Voltage (SD, FS)..............-0.3V to (V

CC_

+ 0.3V)

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

CC_

+ 0.3V)

Output Switch Voltage (D1, D2).......................................+12V

With Respect to ISO COM_

Control Input Voltage (ISO DE_) ....-0.3V to (ISO V

CC_

+ 0.3V)

Driver Input Voltage (ISO DI_) .......-0.3V to (ISO V

CC_

+ 0.3V)

Receiver Output Voltage (ISO RO_)

..-0.3V to (ISO V

CC_

+ 0.3V)

Driver Output Voltage (A, B, Y, Z) ......................-8V to +12.5V

Receiver Input Voltage (A, B).............................-8V to +12.5V

LED Forward Current (DI, DE, ISO RO LED) ......................50mA

Continuous Power Dissipation (T

A

= +70°C)

24-Pin Plastic DIP (derate 8.7mW°C above +70°C) ....696mW

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

Operating Temperature Ranges

MAX1480E_CPI/MAX1490E_CPI ........................0°C to +70°C

MAX1480E_EPI/MAX1490E_EPI......................-40°C to +85°C

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

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

Operating Supply Current I

CC

1.5 5R = 27Ω (RS-485), Figure 4

R = 50Ω (RS-422)

V

2

V

OD2

Differential Driver Output
(with Load)

VFS= 0

CONDITIONS

535f

SWL

UNITSMIN TYP MAXSYMBOLPARAMETER

FS = V

CC_

or open 725f

SWH

85 120

55 120

MAX1480EA,
DE

´ = V

CC_

or open

145

130

Low

V

0.8V

SDL

MAX1480EC,
DE

´ = V

CC_

or open

Shutdown Input Threshold

SD = V

CC_

High

µA0.2I

SHDN

Shutdown Supply Current
(Note 3)

2.4V

SDH

120

65 125

High
Low

2.4V

FSH

V

0.8V

FSL

FS Input Threshold

DE´, DI´, Figures 1 and 2
DE´, DI´, Figures 1 and 2

VVCC- 0.4V

IH

Input High Voltage

V0.4V

IL

Input Low Voltage

FS low

FS high

µA50FS Input Pullup Current

pA10FS Input Leakage Current

pA10

Shutdown Input Leakage
Current

RL= ∞
RL= 54Ω
RL= ∞
RL= 54Ω

RL= ∞

MAX1490EB

RL= 54Ω

TA= +25°C, f = 1MHz pF10C

ISO

Isolation Capacitance

TA= +25°C, V

ISO

= 50VDC MΩ100 10,000R

ISO

Isolation Resistance

kHzSwitch Frequency

mA

RL= ∞
RL= 54Ω

130 180

MAX1490EA

180

V8V

OD1

Differential Driver Output
(No Load)

TA= +25°C, 1min (Note 4) V

RMS

1260V

ISO

Isolation Voltage

MAX1480E/MAX1490E

±15kV ESD-Protected, Isolated RS-485/RS-422

Data Interfaces

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(V

CC_

= +5V ±10%, VFS= V

CC_

, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at V

CC_

= +5V and TA= +25°C.)

(Notes 1, 2)

SWITCHING CHARACTERISTICS—MAX1480EA/MAX1490EA

(V

CC_

= +5V ±10%, VFS= V

CC_

, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at V

CC_

= +5V and TA= +25°C.)

Driver Disable Time from Low
(MAX1480EA Only)

t

LZ

0.5 1.8 µsFigures 6 and 8, CL= 15pF, S1 closed

Driver Disable Time from High
(MAX1480EA Only)

t

HZ

0.5 1.8 µsFigures 6 and 8, CL= 15pF, S2 closed

Driver Enable to Output Low
(MAX1480EA Only)

t

ZL

1.0 1.8 µsFigures 6 and 8, CL= 100pF, S1 closed

PARAMETER SYMBOL MIN TYP MAX UNITS

Driver Rise or Fall Time t

R, tF

15 50 ns

Receiver Input to Output
Propagation Delay

t

PHL

90 225

ns

Figures 5 and 7, R

DIFF

= 54Ω, CL1= CL2= 100pF

t

PLH

120 225

Driver Enable to Output High
(MAX1480EA Only)

t

ZH

1.0 1.8 µs

Figures 5 and 10, R

DIFF

= 54Ω, CL1= CL2= 100pF

Figures 6 and 8, CL= 100pF, S2 closed

t

PLH

90 275

Figures 5 and 7, R

DIFF

= 54Ω,

CL1= CL2= 100pF

Driver Output Skew

CONDITIONS

t

SKEW

30 100 ns

Driver Input to Output
Propagation Delay

t

PHL

60 275

ns

Figures 5 and 7, R

DIFF

= 54Ω, CL1= CL2= 100pF

-7V ≤ VCM≤ +12V VV

TH

Receiver Differential Threshold

A, B, Y, and Z pins, tested using Human Body
Model, Figures 1 and 2

kVISO I

OSD

ESD Protection

R = 27Ω or 50Ω, Figure 4 V

0.3

∆V

OD

CONDITIONS

Change in Magnitude of
Driver Output Voltage for
Complementary Output States

mA

0.25

R = 27Ω or 50Ω, Figure 4

VCM= 0

kΩR

IN

Receiver Input Resistance

mV∆V

TH

Receiver Input Hysteresis

V4V

OC

Driver Common-Mode Output

1.0

UNITSMIN TYP MAXSYMBOLPARAMETER

V

OUT

= 5.5V µAI

OH

Receiver Output High Current

Using resistor values listed in Tables 1 and 2

-7V ≤ VO≤ 12V (Note 5) mAISO I

OSD

Driver Short-Circuit Current

VV

OL

Receiver Output Low Voltage

Differential

Common mode 0.3

MAX1490EA/
MAX1490EB

MAX1480EA/
MAX1480EC

MAX1480EA/
MAX1480EC

MAX1490EA/
MAX1490EB

0.2

ISO I

IN

Input Current (A, B)

0.8

DE´ = 0,
V

CC_

= 0 or +5.5V

VIN= +12V

VIN= -7V

12

-0.2 0.2

70

0.4

250

100

±15

-7V ≤ VCM≤ +12V

48

(MAX1490E_)

(MAX1480E_)

MAX1480E/MAX1490E

±15kV ESD-Protected, Isolated RS-485/RS-422
Data Interfaces

4 _______________________________________________________________________________________

Note 1: All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to logic-

side ground (GND_), unless otherwise specified.

Note 2: For DE

´ and DI´ pin descriptions, see Detailed Block Diagram and Typical Application Circuit (Figure 1 for MAX1480EA/

MAX1480EC, Figure 2 for MAX1490EA/MAX1490EB).

Note 3: Shutdown supply current is the current at V

CC1

and V

CC2

when shutdown is enabled.

Note 4: Limit guaranteed by applying 1520V

RMS

for 1s. Test voltage is applied between all pins on one side of the package to all

pins on the other side of the package, e.g., between pins 1–14 and pins 15–28 on the 28-pin package.

Note 5: Applies to peak current (see Typical Operating Characteristics). Although the MAX1480EA/MAX1480EC and

MAX1490EA/MAX1490EB provide electrical isolation between logic ground and signal paths, they do not provide isolation
between external shields and the signal paths (see Isolated Common Connection section).

SWITCHING CHARACTERISTICS—MAX1480EA/MAX1490EA (continued)

(V

CC_

= +5V ±10%, VFS= V

CC_

, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at V

CC_

= +5V and TA= +25°C.)

t

ZH(SHDN)

315Figures 6 and 9, CL= 100pF, S2 closedShutdown to Driver Output High

t

ZH(SHDN)

315

µs

Figures 6 and 9, CL= 100pF, S1 closed

PARAMETER SYMBOL MIN TYP MAX UNITSCONDITIONS

Shutdown to Driver Output Low µs

t

PLH

1.4 3.0Figures 5 and 7, R

DIFF

= 54Ω, CL1= CL2= 100pF

Driver Input to Output
Propagation Delay

t

PHL

1.1 3.0

µs

Figures 5 and 7, R

DIFF

= 54Ω, CL1= CL2= 100pF

Driver Disable Time from High
(MAX1480EC Only)

t

HZ

1.7 4.5 µsFigures 6 and 8, CL= 15pF, S2 closed

Driver Disable Time from Low
(MAX1480EC Only)

t

LZ

2.0 4.5 µsFigures 6 and 8, CL= 15pF, S1 closed

Driver Enable to Output Low
(MAX1480EC Only)

t

ZL

1.4 4.5 µsFigures 6 and 8, CL= 100pF, S1 closed

Driver Enable to Output High
(MAX1480EC Only)

t

ZH

1.4 4.5 µsFigures 6 and 8, CL= 100pF, S2 closed

Time to Shutdown t

SHDN

100 µs

PARAMETER SYMBOL MIN TYP MAX UNITS

Driver Rise or Fall Time t

R, tF

1.0 2.0 µs

|t

PLH

- t

PHL

| Differential

Receiver Skew

t

SKD

200 ns

Receiver Input to Output
Propagation Delay

t

PHL

1.1 3.0

µs

Figures 5 and 10, R

DIFF

= 54Ω, CL1= CL2= 100pF

Maximum Data Rate

Figures 5 and 7, R

DIFF

= 54Ω, CL1= CL2= 100pF

f

MAX

160 kbps

Shutdown to Driver Output Low

t

SKEW

, t

SKD

≤ 25% of data period

t

ZL(SHDN)

t

PLH

0.9 3.0

315

Figures 5 and 10, R

DIFF

= 54Ω, CL1= CL2= 100pF

µsFigures 6 and 9, CL= 100pF, S1 closed

Shutdown to Driver Output High t

ZH(SHDN)

315µsFigures 6 and 9, CL= 100pF, S2 closed

Driver Output Skew

CONDITIONS

t

SKEW

300 1200 nsFigures 5 and 7, R

DIFF

= 54Ω, CL1= CL2= 100pF

t

SKD

30 150Figures 5 and 10, R

DIFF

= 54Ω, CL1= CL2= 100pF

|t

PLH

- t

PHL

| Differential

Receiver Skew

ns

SWITCHING CHARACTERISTICS—MAX1480EC/MAX1490EB

(V

CC_

= +5V ±10%, VFS= V

CC_

, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at V

CC_

= +5V and TA= +25°C.)

t

SHDN

100Time to Shutdown µs

f

MAX

2.5t

SKEW

, t

SKD

, t

PHL

≤ 25% of data periodMaximum Data Rate Mbps

MAX1480E/MAX1490E

±15kV ESD-Protected, Isolated RS-485/RS-422

Data Interfaces

_______________________________________________________________________________________ 5

__________________________________________Typical Operating Characteristics

(V

CC_

= +5V, VFS= V

CC_

, Figures 1 and 2, TA = +25°C, unless otherwise noted.)

OUTPUT CURRENT vs.

RECEIVER OUTPUT LOW VOLTAGE

80

MEASURED AT ISO RO DRV

70

60

50

40

30

OUTPUT CURRENT (mA)

20

10

0

1.00.50 3.53.02.52.0 5.04.54.0
OUTPUT LOW VOLTAGE (V)

RECEIVER OUTPUT LOW VOLTAGE

vs. TEMPERATURE

0.8
MEASURED AT ISO RO DRV

I

= 8mA

RO

0.7

0.6

0.5

0.4

0.3

OUTPUT LOW VOLTAGE (V)

0.2

0.1

0

-40 20

DRIVER OUTPUT CURRENT

vs. DIFFERENTIAL OUTPUT VOLTAGE

80

70

60

50

40

30

OUTPUT CURRENT (mA)

20

10

0

1.00.50 3.53.02.52.0 5.04.54.0

DIFFERENTIAL OUTPUT VOLTAGE (V)

OUTPUT CURRENT vs.

RECEIVER OUTPUT HIGH VOLTAGE

-30
MEASURED AT ISO RO DRV

-25

MAX1480E/90E TOC01

-20

-15

-10

OUTPUT CURRENT (mA)

-5

1.5

0

1.00.50 3.53.02.52.0 5.04.54.0

1.5

OUTPUT HIGH VOLTAGE (V)

OUTPUT CURRENT vs.

DRIVER OUTPUT LOW VOLTAGE

180

160

140

MAX1480E/90E TOC04

120

100

80

60

OUTPUT CURRENT (mA)

40

20

0

123456789101112

0-20 6040 80
TEMPERATURE (°C)

0

OUTPUT LOW VOLTAGE (V)

DRIVER DIFFERENTIAL OUTPUT VOLTAGE

vs. TEMPERATURE

3.0

DI´ = HIGH OR OPEN

MAX1480E/90E TOC07

1.5

DI´ = HIGH OR OPEN

2.9

= 54Ω

R

L

2.8

2.7

2.6

2.5

2.4

2.3

2.2

DIFFERENTIAL OUTPUT VOLTAGE (V)

2.1

2.0

-40 20

0-20 6040 80
TEMPERATURE (°C)

5.00
MEASURED AT ISO RO DRV

I

4.75

4.50

MAX1480E/90E TOC02

4.25

4.00

3.75

OUTPUT HIGH VOLTAGE (V)

3.50

3.25

3.00

-40 20

-100

-90

-80

MAX1480E/90E TOC05

-70

-60

-50

-40

-30

OUTPUT CURRENT (mA)

-20

-10

0

-7

0.40

0.35

0.30

MAX1480E/90E TOC08

0.25

0.20

0.15

SHUTDOWN CURRENT (µA)

0.10

0.05

0

-40 20

RECEIVER OUTPUT HIGH VOLTAGE

vs. TEMPERATURE

= 8mA

RO

0-20 6040 80
TEMPERATURE (°C)

OUTPUT CURRENT vs.

DRIVER OUTPUT HIGH VOLTAGE

-6 -5 -4 -3 -2 -1 1 2 3 4 5 6
OUTPUT HIGH VOLTAGE (V)

0

SHUTDOWN CURRENT

vs. TEMPERATURE

SD = V

, DI´ = V

CC_

DE´= V
MEASURED AT V

CC_

(MAX1480EC ONLY)

CC_

AND V

CC1

CC2

0-20 6040 80
TEMPERATURE (°C)

MAX1480E/90E TOC03

MAX1480E/90E TOC06

MAX1480E/90E TOC09

MAX1480E/MAX1490E

±15kV ESD-Protected, Isolated RS-485/RS-422
Data Interfaces

6 _______________________________________________________________________________________

____________________________Typical Operating Characteristics (continued)

(V

CC_

= +5V, VFS= V

CC_

, Figures 1 and 2, TA = +25°C, unless otherwise noted.)

V

CC_

= 5.0V, DE´= V

CC_

MAX1480EA/MAX1490EA

RECEIVER t

PHL

RO
2V/div

20ns/div

RECEIVER
INPUT A
1V/div

RECEIVER
INPUT B
1V/div

MAX1480E/90E toc14

V

CC_

= 5.0V, DE´= V

CC_

MAX1480EA/MAX1490EA

RECEIVER t

PLH

RO
2V/div

20ns/div

RECEIVER
INPUT B
1V/div

RECEIVER
INPUT A
1V/div

MAX1480E/90E toc15

SUPPLY CURRENT vs. TEMPERATURE

160

DE´ = V

V

CC

V

V

CC

= +5.5V

140

120

100

80

60

SUPPLY CURRENT (mA)

40

20

0

-40 -20 0 20 40 60 80

MAX1480EA

SUPPLY CURRENT vs. TEMPERATURE

= +5.5V

CC

= +5V

V

CC

= +4.5V

CC

V

= +4.5V

V

CC

TEMPERATURE (°C)

= 54Ω

R

L

= ∞

R

L

= +5V

CC

120

110

100

MAX1480E/90E TOC10

90

80

70

60

50

SUPPLY CURRENT (mA)

40

30

20

-40 -20 0 20 40 60 80

DE´ = V

V

CC

V

CC

V

CC

CC

= +5V

V

CC

TEMPERATURE (°C)

MAX1480EC

= +5.5V

= +5V

= +4.5V

= +5.5V

V

CC

SUPPLY CURRENT vs. TEMPERATURE

MAX1490EA

= 54Ω

R

L

= ∞

R

L

= +4.5V

V

CC

200

180

MAX1480E/90E T0C11

160

140

120

SUPPLY CURRENT (mA)

100

= +5.5V

V

CC

= +5V

V

CC

= +4.5V

V

CC

= +5.5V

V

CC

= +5V

V

CC

= +4.5V

V

80

-40 -20 0 20 40 60 80

TEMPERATURE (°C)

CC

R

L

R

L

= 54Ω

= ∞

MAX1480E/90E TOC12

SUPPLY CURRENT vs. TEMPERATURE

150

140

130

120

110

100

90

80

SUPPLY CURRENT (mA)

70

60

50

-40 -20 0 20 40 60 80

MAX1490EB

V

V

= +5V

V

CC

TEMPERATURE (°C)

V

CC

CC

CC

= +5.5V

= +5V

= +4.5V

V

CC

= +5.5V

MAX1480E/90E TOC13

= 54Ω

R

L

= ∞

R

L

= +4.5V

V

CC