SP485ECN-L/TR - Exar - Pdf.Support

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

DESCRIPTION

• +5V Only

• Low Power BiCMOS

• Driver / Receiver Enable for Multi-Drop

congurations

• Low Power Shutdown mode (SP481E)

• Enhanced ESD Specications:

+/-15kV Human Body Model

+/-15kV IEC1000-4-2 Air Discharge

+/-8kV IEC1000-4-2 Contact Discharge

• Available in RoHS Compliant, Lead Free

Packaging.

SP481E / SP485E

Enhanced Low Power Half-Duplex

RS-485 Transceivers

The SP481E and SP485E are a family of half-duplex transceivers that meet the specica-

tions of RS-485 and RS-422 serial protocols with enhanced ESD performance. The ESD

tolerance has been improved on these devices to over +15kV for both Human Body Model

and IEC1000-4-2 Air Discharge Method. These devices are pin-to-pin compatible with Exar's

SP481 and SP485 devices as well as popular industry standards. As with the original ver-

sions, the SP481E and SP485E feature Exar's BiCMOS design allowing low power opera-

tion without sacricing performance. The SP481E and SP485E meet the requirements of

the RS-485 and RS-422 protocols up to 10Mbps under load. The SP481E is equipped with

a low power shutdown mode.

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

ABSOLUTE MAXIMUM RATINGS

These are stress ratings only and functional operation

of the device at these ratings or any other above those

indicated in the operation sections of the specications

below is not implied. Exposure to absolute maximum

rating conditions for extended periods of time may

affect reliability.

VCC.......................................................................+7V

Input Voltages

Logic.........................-0.3V to (Vcc + 0.5V)

Drivers......................-0.3V to (Vcc + 0.5V)

Receivers.........................................+/-15V

ELECTRICAL CHARACTERISTICS

TMIN to TMAX and VCC = +5.0V +/-5% unless otherwise noted.

PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS

SP481E/SP485E DRIVER

DC Characteristics

Differential Output Voltage GND Vcc Volts Unloaded; R = ∞ ; see Figure 1

Differential Output Voltage 2 Vcc Volts With Load; R = 50Ω (RS-422); see

Figure 1

Differential Output Voltage 1.5 Vcc Volts With Load; R = 27Ω (RS-485); see

Figure 1

Change in Magnitude of Driver

Differential Output Voltage for

Complimentary states

0.2 Volts R = 27Ω or R = 50Ω; see Figure 1

Driver Common Mode Output

Voltage

3Volts R = 27Ω or R = 50Ω; see Figure 1

Input High Voltage 2.0 Volts Applies to DE, DI, RE

Input Low Voltage 0.8 Volts Applies to DE, DI, RE

Input Current +/-10 µA Applies to DE, DI, RE

Driver Short Circuit Current

VOUT = HIGH +/-250 mA -7V ≤ VO ≤ +12V

VOUT = LOW +/-250 mA -7V ≤ VO ≤ +12V

SP481E/SP485E DRIVER

AC Characteristics

Max. Transmission Rate 10 Mbps RE = 5V, DE = 5V; RDIFF = 54Ω,

CL1 = CL2 = 100pF

Driver Input to Output, tPLH 30 60 ns See Figures 3 & 5, RDIFF = 54Ω,

CL1 = CL2 = 100pF

Driver Input to Output, tPLH

(SP485EMN ONLY)

30 80 ns

Driver Input to Output, tPHL 30 60 ns See Figures 3 & 5, RDIFF = 54Ω,

CL1 = CL2 = 100pF

Driver Input to Output, tPHL

(SP485EMN ONLY)

30 80 ns

Driver Skew 5 10 ns see Figures 3 and 5,

tSKEW = |tDPHL - tDPLH|

Driver Rise or Fall Time 15 40 ns From 10%-90%; RDIFF = 54Ω

CL1 = CL2 = 100pF; see Figures 3

and 6

Output Voltages

Logic.........................-0.3V to (Vcc + 0.5V)

Drivers.............................................+/-15V

Receivers..................-0.3V to (Vcc + 0.5V)

Storage Temperature.......................-65˚C to +150˚C

Power Dissipation

8-pin NSOIC...................................................550mW

(derate 6.60mW/ºC above +70ºC)

8-pin PDIP....................................................1000mW

(derate 11.8mW/ºC above +70ºC)

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS

SP481E/SP485E DRIVER (continued)

AC Characteristics

Driver Enable to Output High 40 70 ns CL = 100pF, see Figures 4 and 6,

S2 closed

Driver Enable to Output Low 40 70 ns CL = 100pF, see Figures 4 and 6,

S1 closed

Driver Disable Time from High 40 70 ns CL = 100pF, see Figures 4 and 6,

S2 closed

Driver Disable Time from Low 40 70 ns CL = 100pF, see Figures 4 and 6,

S1 closed

SP481E/SP485E RECEIVER

DC Characteristics

Differential Input Threshold -0.2 +0.2 Volts -7V ≤ VCM ≤ +12V

Differential Input Threshold

(SP485EMN ONLY)

-0.4 +0.4 Volts -7V ≤ VCM ≤ +12V

Input Hysteresis 20 mV VCM = 0V

Output Voltage High 3.5 Volts IO = -4mA, VID = +200mV

Output Voltage Low 0.4 Volts IO = +4mA, VID = +200mV

Three-State ( High Impedance)

Output Current

+/-1 µA 0.4V ≤ VO ≤ 2.4V; RE = 5V

Input Resistance 12 15 kΩ -7V ≤ VCM ≤ +12V

Input Current (A, B); VIN = 12V +1.0 mA DE = 0V, VCC = 0V or 5.25V,

VIN = 12V

Input Current (A, B); VIN = -7V -0.8 mA DE = 0V, VCC = 0V or 5.25V,

VIN = -7V

Short Circuit Current 7 95 mA 0V ≤ VO ≤ VCC

SP481E/SP485E RECEIVER

AC Characteristics

Max. Transmission Rate 10 Mbps RE = 0V, DE = 0V

Receiver Input to Output 20 45 100 ns tPLH ; See Figures 3 & 7, RDIFF =

54Ω, CL1 = CL2 = 100pF

Receiver Input to Output 20 45 100 ns tPHL ; See Figures 3 & 7, RDIFF =

54Ω, CL1 = CL2 = 100pF

Differential Receiver Skew

|tPHL - tPLH|

13 ns RDIFF = 54Ω, CL1 = CL2 = 100pF, see

Figures 3 and 7

Receiver Enable to Output Low 45 70 ns CRL = 15pF, Figures 2 & 8; S1

Closed

Receiver Enable to Output High 45 70 ns CRL = 15pF, Figures 2 & 8; S2

Closed

Receiver Disable from LOW 45 70 ns CRL = 15pF, Figures 2 & 8; S1

Closed

Receiver Disable from High 45 70 ns CRL = 15pF, Figures 2 & 8; S2

Closed

ELECTRICAL CHARACTERISTICS

TMIN to TMAX and VCC = +5.0V +/-5% unless otherwise noted.

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS

SP481E

Shutdown Timing

Time to Shutdown 50 200 600 ns RE = 5V, DE = 0V

Driver Enable from Shutdown

to Output High

40 100 ns CL = 100pF; See Figures 4 and 6;

S2 Closed

Driver Enable from Shutdown

to Output Low

40 100 ns CL = 100pF; See Figures 4 and 6;

S1 Closed

Receiver Enable from

Shutdown to Output High

300 1000 ns CL = 15pF; See Figures 2 and 8; S2

Closed

Receiver Enable from

Shutdown to Output Low

300 1000 ns CL = 15pF; See Figures 2 and 8; S1

Closed

POWER REQUIREMENTS

Supply Voltage VCC +4.75 +5.25 Volts

Supply Current

SP481E/SP485E

No Load 900 µA RE, DI = 0V or VCC; DE = VCC

600 µA RE = 0V, DI = 0V or 5V; DE = 0V

SP481E

Shutdown Mode 10 µA DE = 0V, RE = VCC

ENVIRONMENTAL AND MECHANICAL

Operating Temperature

Commercial (_C_) 0 70 ºC

Industrial (_E_) -40 +85 ºC

(_M_) -40 +125 ºC

Storage Temperature -65 +150 ºC

Package

Plastic DIP (_P)

NSOIC (_N)

ELECTRICAL CHARACTERISTICS

TMIN to TMAX and VCC = +5.0V +/-5% unless otherwise noted.

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

PIN FUNCTION

TEST CIRCUITS

Figure 1. RS-485 Driver DC Test Load Circuit

CL1

15pF

CL2

Figure 3. RS-485 Driver/Receiver Timing Test

500Ω

Output

Under

Test

VCC

Figure 4. Driver Timing Test Load #2 Circuit

Figure 2. Receiver Timing Test Load Circuit

1kΩ

1kΩCRL

Receiver

Output S1

Test Point

VCC

Pin 1 - RO - Receiver Output

Pin 2 - RE - Receiver Output Enable Active LOW

Pin 3 - DE - Driver Output Enable Active HIGH

Pin 4 DI - Driver Input

Pin 5 - GND - Ground Connection

Pin 6 - A - Driver Output / Receiver input

Non-Inverting

Pin 7 - B - Driver Output / Receiver Input Inverting

Pin 8 - Vcc - Positive Supply 4.75V ≤ Vcc ≤ 5.25V

Figure 5. Driver Propagation Delays

+3V

DRIVER INPUT

DRIVER

OUTPUT

VO+

DIFFERENTIAL

OUTPUT

VA – VB

VO–

1.5V 1.5V

tPLH

≤ 10ns;

tF ≤ 10ns

VO1/2V

O1/2V

tPHL

tSKEW

= |tDPLH

- tDPHL|

tDPLH tDPHL

f ≥

1MHz;

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

Figure 6. Driver Enable and Disable Times

Figure 8. Receiver Enable and Disable Times

+3V

VOL

, B

1.5V 1.5V

tZL

tZH

f = 1MHz; tR

< 10ns; tF < 10ns

VOH

, B 2.3V

2.3V

tLZ

tHZ

0.5V

Output normally LOW

Output normally HIGH

SWITCHING WAVEFORMS

FUNCTION TRUTH TABLES

INPUTS OUTPUTS

RE DE DI

LINE

CONDITION A B

X 1 1 No Fault 1 0

X 1 0 No Fault 0 1

X 0 X X Z Z

X 1 X Fault Z Z

Table 1. Transmit Function Truth Table

INPUTS OUTPUTS

RE DE A - B R

0 0 +0.2V 1

0 0 -0.2V 0

0 0 Inputs Open 1

1 0 X Z

Table 2. Receive Function Truth Table

VOH

VOL

R1.5V 1.5V

tPHL

f = 1MHz; tR 10ns; tF

≤ 10ns

OUTPUT

VOD2+

VOD2–

– B 0V 0V

tPLH

INPUT

≤

+3V

1.5V 1.5V

f = 1MHz; t

≤ 10ns; t

≤ 10ns

R1.5V

1.5V

0.5V

Output normally LOW

Output normally HIGH

Figure 7. Receiver Propagation Delays

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

The SP481E and SP485E are half-duplex

differential transceivers that meet the require-

ments of RS-485 and RS-422. Fabricated

with an Exar proprietary BiCMOS process,

this product requires a fraction of the power

of older bipolar designs.

The RS-485 standard is ideal for multi-drop

applications and for long-distance interfaces.

RS-485 allows up to 32 drivers and 32 receiv-

ers to be connected to a data bus, making it

an ideal choice for multi-drop applications.

Since the cabling can be as long as 4,000

feet, RS-485 transceivers are equipped with

a wide (-7V to +12V) common mode range

to accommodate ground potential differ-

ences. Because RS-485 is a differential

interface, data is virtually immune to noise

in the transmission line.

Drivers

The driver outputs of the SP481E and

SP485E are differential outputs meeting the

RS-485 and RS-422 standards. The typical

voltage output swing with no load will be 0

Volts to +5 Volts. With worst case loading

of 54Ω across the differential outputs, the

drivers can maintain greater than 1.5V volt-

age levels. The drivers of the SP481E and

SP485E have an enable control line which

is active HIGH. A logic HIGH on DE (pin 3)

will enable the differential driver outputs. A

logic LOW on the DE(pin 3) will tri-state the

driver outputs.

The transmitters of the SP481E and SP485E

will operate up to at least 10Mbps.

Receivers

The SP481E and SP485E receivers have

differential inputs with an input sensitivity

as low as ±200mV. Input impedance of the

receivers is typically 15kΩ (12kΩ minimum).

A wide common mode range of -7V to +12V

allows for large ground potential differences

between systems. The receivers of the

SP481E and SP485E have a tri-state en-

able control pin. A logic LOW on RE (pin 2)

will enable the receiver, a logic HIGH on RE

(pin 2) will disable the receiver.

The receiver for the SP481E and SP485E

will operate up to at least 10Mbps. The

receiver for each of the two devices is

equipped with the fail-safe feature. Fail-

safe guarantees that the receiver output

will be in a HIGH state when the input is

left unconnected.

Shutdown Mode

SP481E

The SP481E is equipped with a Shutdown

mode. TO enable the shutdown state, both

driver and receiver must be disabled simul-

taneously. A logic LOW on DE (pin 3) and a

Logic HIGH on RE (pin 2) will put the SP481E

into Shutdown mode. In Shutdown, supply

current will drop to typically 1µA.

ESD TOLERANCE

The SP481E and SP485E incorporates

ruggedized ESD cells on all driver output

and receiver input pins. The ESD structure

is improved over our previous family for

more rugged applications and environments

sensitive to electro-static discharges and

associated transients. The improved ESD

tolerance is at least ±15kV without damage

or latch-up.

There are different methods of ESD testing

applied:

a) MIL-STD-883, Method 3015.7

b) IEC61000-4-2 Air-Discharge

c) IEC61000-4-2 Direct Contact

DESCRIPTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

The Human Body Model has been the

generally accepted ESD testing method

for semiconductors. This method is also

specied in MIL-STD-883, Method 3015.7

for ESD testing. The premise of this ESD

test is to simulate the human body’s potential

to store electro-static energy and discharge

it to an integrated circuit. The simulation is

performed by using a test model as shown

in Figure 9. This method will test the IC’s

capability to withstand an ESD transient dur-

ing normal handling such as in manufactur-

ing areas where the ICs tend to be handled

frequently. The IEC-61000-4-2, formerly

IEC801-2, is generally used for testing ESD

on equipment and systems.

For system manufacturers, they must guar-

antee a certain amount of ESD protection

since the system itself is exposed to the

outside environment and human presence.

The premise with IEC61000-4-2 is that the

system is required to withstand an amount

of static electricity when ESD is applied to

points and surfaces of the equipment that

are accessible to personnel during normal

usage. The transceiver IC receives most

of the ESD current when the ESD source is

applied to the connector pins. The test circuit

for IEC61000-4-2 is shown on Figure 10.

There are two methods within IEC61000-4-2,

the Air Discharge method and the Contact

Discharge method.

Device

Under

Test

DC Power

Source

SW1 SW2

and

add up to 330Ω for IEC61000-4-2.

Device

Under

Test

DC Power

Source

SW1 SW2

Contact-Discharge Model

Figure 9. ESD Test Circuit for Human Body Model

Figure 10. ESD Test Circuit for IEC61000-4-2

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

With the Air Discharge Method, an ESD

voltage is applied to the equipment under

test (EUT) through air. This simulates an

electrically charged person ready to connect

a cable onto the rear of the system only to

nd an unpleasant zap just before the person

touches the back panel. The high energy

potential on the person discharges through

an arcing path to the rear panel of the system

before he or she even touches the system.

This energy, whether discharged directly or

through air, is predominantly a function of the

discharge current rather than the discharge

voltage. Variables with an air discharge such

as approach speed of the object carrying the

ESD potential to the system and humidity

will tend to change the discharge current.

For example, the rise time of the discharge

current varies with the approach speed.

The Contact Discharge Method applies the

ESD current directly to the EUT. This method

was devised to reduce the unpredictability

of the ESD arc. The discharge current rise

time is constant since the energy is directly

transferred without the air-gap arc. In situ-

ations such as hand held systems, the ESD

charge can be directly discharged to the

equipment from a person already holding

the equipment. The current is transferred

on to the keypad or the serial port of the

equipment directly and then travels through

the PCB and nally to the IC.

The circuit model in Figures 9 and 10 repre-

sent the typical ESD testing circuit used for

all three methods. The CS is initially charged

with the DC power supply when the rst

switch (SW1) is on. Now that the capacitor

is charged, the second switch (SW2) is on

while SW1 switches off.

t = 0ns t = 30ns

15A

30A

I →

t →

Figure 11. ESD Test Waveform for IEC61000-4-2

The voltage stored in the capacitor is then

applied through RS, the current limiting

resistor, onto the device under test (DUT).

In ESD tests, the SW2 switch is pulsed so

that the device under test receives a dura-

tion of voltage.

For the Human Body Model, the current

limiting resistor (RS) and the source capacitor

(CS) are 1.5kΩ an 100pF, respectively. For

IEC-61000-4-2, the current limiting resistor

(RS) and the source capacitor (CS) are 330Ω

an 150pF, respectively.

The higher CS value and lower RS value in

the IEC61000-4-2 model are more stringent

than the Human Body Model. The larger

storage capacitor injects a higher voltage

to the test point when SW2 is switched on.

The lower current limiting resistor increases

the current charge onto the test point.

SP481E, SP485E

FAMILY

HUMAN BODY

MODEL

IEC61000-4-2

Air Discharge Direct Contact Level

Driver Outputs

Receiver Inputs

+/-15kV

+/-8kV

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP481E,485E_103_052711

ORDERING INFORMATION

Model Temperature Range Package Types

SP481ECN-L ....................................................................... 0°C to +70°C ................................................................................................8-pin NSOIC

SP481ECN-L/TR ................................................................. 0°C to +70°C ................................................................................................8-pin NSOIC

SP481EEN-L/.................................................................... -40°C to +85°C...............................................................................................8-pin NSOIC

SP481EEN-L/TR................................................................. -40°C to +85°C.............................................................................................8-pin NSOIC

SP485ECN-L ....................................................................... 0°C to +70°C ................................................................................................8-pin NSOIC

SP485ECN-L/TR ................................................................. 0°C to +70°C ................................................................................................8-pin NSOIC

SP485ECP-L....................................................................... 0°C to +70°C.................................................................................................8-pin PDIP

SP485EEN-L..................................................................... -40°C to +85°C................................................................................................8-pin NSOIC

SP485EEN-L/TR................................................................ -40°C to +85°C...............................................................................................8-pin NSOIC

SP485EEP-L...................................................................... -40°C to +85°C...............................................................................................8-pin PDIP

SP485EMN-L..................................................................... -40°C to +125°C.............................................................................................8-pin NSOIC

SP485EMN-L/TR............................................................... -40°C to +125°C.............................................................................................8-pin NSOIC

REVISION HISTORY

DATE REVISION DESCRIPTION

May 11/07 -- Legacy Sipex Datasheet

12/18/08 1.0.0 Convert to Exar Format. Update ordering information as a result of discontinued

Lead type package options per PDN 081126-01. Remove "Top Mark" information

from ordering page.

11/19/09 1.0.1 Correct table 1 error for driver output A and B outputs

08/08/10 1.0.2 Change SP485EMN-L and SP485EMN-L/TR temperature range error from +85C to

+125C in ordering information section.

05/27/11 1.0.3 Remove driver minimum limits of propagation delay and Rise/Fall time. Remove

SP481ECP-L and SP481EEP-L per PDN 110510-01

Notice

EXAR Corporation reserves the right to make changes to any products contained in this publication in order to improve design, performance or reliabil-

ity. EXAR Corporation assumes no representation that the circuits are free of patent infringement. Charts and schedules contained herein are only for

illustration purposes and may vary depending upon a user's specic application. While the information in this publication has been carefully checked;

no responsibility, however, is assumed for inaccuracies.

EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can

reasonably be expected to cause failure of the life support system or to signicantly affect its safety or effectiveness. Products are not authorized for

use in such applications unless EXAR Corporation receives, in writting, assurances to its satisfaction that: (a) the risk of injury or damage has been

minimized ; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances.

Datasheet May 2011

Send your Interface technical inquiry with technical details to: uarttechsupport@exar.com

Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.

Note: /TR = Tape and Reel