SP485EEN-L/TR - Sipex Corporation

SP481E/SP485E

■+5V Only

■Low Power BiCMOS

■Driver/Receiver Enable for Multi-Drop

configurations

■Low Power Shutdown Mode

(SP481E)

■Enhanced ESD Specifications:

DESCRIPTION

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

specifications 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

Sipex's SP481 and SP485 devices as well as popular industry standards. As with the original

versions, the SP481E and the SP485E feature Sipex's BiCMOS design allowing low power

operation without sacrificing 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.

+15KV Human Body Model

+15KV IEC1000-4-2 Air Discharge

+8KV IEC1000-4-2 Contact Discharge

Enhanced Low Power Half-Duplex

RS-485 Transceivers

RO 1

RE 2

DE 3

DI 4

8 Vcc

7 B

6 A

5 GND

SP481E and SP485E

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 specifications 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

SPECIFICATIONS

TMIN to TMAX and VCC = 5V ± 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 3 Volts 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 µAApplies 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

Maximum Data Rate 10 Mbps RE = 5V, DE = 5V; RDIFF = 54Ω,

CL1 = CL2 = 100pF

Driver Input to Output 20 30 60 ns tPLH; RDIFF = 54Ω, CL1 = CL2 = 100pF;

see Figures 3 and 5

Driver Input to Output 20 30 80 ns tPLH; RDIFF = 54Ω, CLI = CL2 = 100pF;

(SP485EMN ONLY) See Figures 3 and 5

Driver Input to Output 20 30 60 ns tPHL; RDIFF = 54Ω, CL1 = CL2 = 100pF;

see Figures 3 and 5

Driver Input to Output 20 30 80 ns tPHL; RDIFF = 54Ω, CL1 = CL2 = 100pF;

(SP485EMN ONLY)

see Figures 3 and 5

Driver Skew 5 10 ns

see Figures 3 and 5,

tSKEW = | tDPLH - tDPHL |

Driver Rise or Fall Time 3 15 40 ns From 10% to 90%; RDIFF = 54Ω,

CL1 = CL2 = 100pF;

ee Figures 3 &

Driver Enable to Output High 40 70 ns CL = 100pF;

see Figures 4 & 6;

closed

Driver Enable to Output Low 40 70 ns CL = 100pF;

see Figures 4 & 6;

closed

Driver Disable Time from Low 40 70 ns CL = 100pF;

see Figures 4 & 6;

closed

Driver Disable Time from High 40 70 ns CL = 100pF;

see Figures 4 & 6;

closed

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 per Package

8-pin NSOIC (derate 6.60mW/oC above +70oC)...........................550mW

8-pin PDIP (derate 11.8mW/oC above +70oC)............................1000mW

SPECIFICATIONS (continued)

TMIN to TMAX and VCC = 5V ± 5% unless otherwise noted.

PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS

SP481E/SP485

E RECEIVER

DC Characteristics

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

Differential Input Threshold -0.4 +0.4 Volts -7V ≤ VCM ≤ +12V

(SP485EMN ONLY)

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 ±1µA 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

Maximum Data Rate 10 Mbps RE = 0V, DE = 0V

Receiver Input to Output 20 45 100 ns tPLH; RDIFF = 54Ω,

CL1 = CL2 = 100pF;

Figures 3 & 7

Receiver Input to Output 20 45 100 ns tPHL; RDIFF = 54Ω,

CL1 = CL2 = 100pF;

Figures 3 & 7

Diff. Receiver Skew ItPLH-tPHLI13 nsR

DIFF = 54Ω; CL1 = CL2 = 100pF;

Figures 3 & 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

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 & 6;

S2 closed

Driver Enable from Shutdown

to Output Low 40 100 ns CL = 100pF;

See Figures 4 & 6;

S1 closed

Receiver Enable from

Shutdown to Output High 300 1000 ns CL = 15pF;

See Figures 2 & 8;

S2 closed

Receiver Enable from

Shutdown to Output Low 300 1000 ns CL = 15pF;

See Figures 2 & 8;

S1 closed

POWER REQUIREMENTS

Supply Voltage +4.75 +5.25 Volts

Supply Current

SP481E/485E

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

600 µARE = 0V, DI = 0V or 5V; DE = 0V

SP481E

Shutdown Mode 10 µADE = 0V, RE=VCC

ENVIRONMENTAL AND MECHANICAL

Operating Temperature

Commercial (_C_) 0 +70 °C

Industrial (_E_) -40 +85 °C

(_M_) -40 +125 °C

Storage Temperature -65 +150 °C

Package

Plastic DIP (_P)

NSOIC (_N)

PIN FUNCTION

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.

SP481E and SP485E

Pinout (Top View)

RO 1

RE 2

DE 3

DI 4

8 VCC

7 B

6 A

5 GND

SP485

Top View

Figure 5. Driver Propagation Delays

Figure 1. RS-485 Driver DC Test Load Circuit Figure 2. Receiver Timing Test Load Circuit

Figure 3. RS-485 Driver/Receiver Timing Test Circuit Figure 4. RS-485 Driver Timing Test Load #2 Circuit

1kTest Point

Receiver

Output

DIFF

15pF S

500

Output

Under

Test

+3V

DRIVER

OUTPUT

DIFFERENTIAL

OUTPUT

– V

–

1.5V 1.5V

PLH

f = 1MHz; t

< 10ns; t

< 10ns

1/2V

PHL

DPLH

DPHL

SKEW =

DPLH -

DPHL

INPUTS OUTPUTS

LINE

RE DE DI CONDITION B A

X1 1No Fault 0 1

X1 0No Fault 1 0

X0X X ZZ

X1X Fault Z Z

INPUTS OUTPUTS

RE DE A - B R

00 +0.2V 1

00 -0.2V 0

00Inputs Open 1

10 X Z

Table 1. Transmit Function Truth Table

Table 2. Receive Function Truth Table

+3V

A, B

1.5V 1.5V

f = 1MHz; t

< 10ns; t

< 10ns

A, B 2.3V

2.3V

0.5V

Output normally LOW

Output normally HIGH

+3V

1.5V 1.5V

tZL

tZH

f = 1MHz; tR < 10ns; tF < 10ns

R1.5V

1.5V

tLZ

tHZ

0.5V

Output normally LOW

Output normally HIGH

VIL

VIH

Figure 8. Receiver Enable and Disable Times

Figure 7. Receiver Propagation Delays

Figure 6. Driver Enable and Disable Times

VOH

VOL

R1.5V 1.5V

tPHL f = 1MHz; tR < 10ns; tF < 10ns

OUTPUT

V0D2+

V0D2–

A – B 0V 0V

tPLH

INPUT

tSKEW = | tPHL - tPLH |

Receivers

The SP481E and SP485E receivers have differ-

ential inputs with an input sensitivity as low as

±200mV. Input impedance of the receivers is

typically 15kΩ (12kΩ minimum). A wide com-

mon 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 enable 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 the driver

and receiver must be disabled simultaneously.

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 Family 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 dis-

charges and associated transients. The improved

ESD tolerance is at least ±15kV without damage

nor latch-up.

There are different methods of ESD testing

applied:

a) MIL-STD-883, Method 3015.7

b) IEC1000-4-2 Air-Discharge

c) IEC1000-4-2 Direct Contact

DESCRIPTION

The SP481E and SP485E are half-duplex differ-

ential transceivers that meet the requirements of

RS-485 and RS-422. Fabricated with a Sipex

proprietary BiCMOS process, all three products

require 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 receivers

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 differences. 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 differ-

ential outputs, the drivers can maintain greater

than 1.5V voltage 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 DE (pin 3) will tri-state the

driver outputs.

The transmitters of the SP481E and SP485E

will operate up to at least 10Mbps.

The Human Body Model has been the generally

accepted ESD testing method for semiconductors.

This method is also specified 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 7. This method will test the

IC’s capability to withstand an ESD transient

during normal handling such as in manufacturing

areas where the ICs tend to be handled frequently.

The IEC-1000-4-2, formerly IEC801-2, is

generally used for testing ESD on equipment and

systems. For system manufacturers, they must

guarantee a certain amount of ESD protection

since the system itself is exposed to the outside

environment and human presence. The premise

with IEC1000-4-2 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

IEC1000-4-2 is shown on Figure 8. There are

two methods within IEC1000-4-2, the Air

Discharge method and the Contact Discharge

method.

SW1

SW2

Device

Under

Test

DC Power

Source

SW1 SW2

Figure 7. ESD Test Circuit for Human Body Model

and

add up to 330

Ω

or IEC1000-4-2.

and

add up to 330Ω for IEC1000-4-2.

Contact-Discharge Module

SW1

SW2

Device

Under

Test

DC Power

Source

SW1 SW2

Contact-Discharge Module

Figure 8. ESD Test Circuit for IEC1000-4-2

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 find 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 situations 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 finally

to the IC.

The circuit model in Figures 7 and 8 represent

the typical ESD testing circuit used for all three

methods. The CS is initially charged with the DC

power supply when the first switch (SW1) is on.

Now that the capacitor is charged, the second

switch (SW2) is on while SW1 switches off. 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 duration 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-1000-4-

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

IEC1000-4-2 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.

Figure 9. ESD Test Waveform for IEC1000-4-2

t=0ns t=30ns

15A

30A

t ➙

i ➙

HUMAN BODY IEC1000-4-2

MODEL Air Discharge Direct Contact Level

Driver Outputs ±15kV ±15kV ±8kV 4

Receiver Inputs ±15kV ±15kV ±8kV 4

SP481E, SP485E

FAMILY

ALTERNATE

END PINS

(BOTH ENDS)

D1 = 0.005" min.

(0.127 min.)

PACKAGE: PLASTIC

DUAL–IN–LINE

(NARROW)

DIMENSIONS (Inches)

Minimum/Maximum

(mm)

A = 0.210" max.

(5.334 max).

A1 = 0.015" min.

(0.381min.)

e = 0.100 BSC

(2.540 BSC)

= 0.300 BSC

(7.620 BSC)

0.115/0.195

(2.921/4.953)

0.014/0.022

(0.356/0.559)

0.045/0.070

(1.143/1.778)

0.008/0.014

(0.203/0.356)

0.355/0.400

(9.017/10.160)

0.300/0.325

(7.620/8.255)

0.240/0.280

(6.096/7.112)

0.115/0.150

(2.921/3.810)

0°/ 15°

(0°/15°)

8–PIN

PACKAGE: PLASTIC

SMALL OUTLINE (SOIC)

(NARROW)

DIMENSIONS (Inches)

Minimum/Maximum

(mm)

8–PIN

h x 45°

0.053/0.069

(1.346/1.748)

0.004/0.010

(0.102/0.249

0.014/0.019

(0.35/0.49)

0.189/0.197

(4.80/5.00)

0.150/0.157

(3.802/3.988)

0.050 BSC

(1.270 BSC)

0.228/0.244

(5.801/6.198)

0.010/0.020

(0.254/0.498)

0.016/0.050

(0.406/1.270)

0°/8°

(0°/8°)

ORDERING INFORMATION

Model Temperature Range Package

SP481ECN ....................................................... 0˚C to +70˚C ............................................... 8-pin Narrow SOIC

SP481ECP ........................................................ 0˚C to +70˚C ................................................... 8-pin Plastic DIP

SP481EEN ...................................................... .-40˚C to +85˚C ............................................. 8-pin Narrow SOIC

SP481EEP ...................................................... -40˚C to +85˚C ................................................. 8-pin Plastic DIP

SP485ECN ....................................................... 0˚C to +70˚C ............................................... 8-pin Narrow SOIC

SP485ECP ........................................................ 0˚C to +70˚C ................................................... 8-pin Plastic DIP

SP485EEN ...................................................... -40˚C to +85˚C ............................................. 8-pin Narrow SOIC

SP485EEP ...................................................... -40˚C to +85˚C ................................................. 8-pin Plastic DIP

SP485EMN .................................................... -40˚C to +125˚C ............................................ 8-pin Narrow SOIC

Please consult the factory for pricing and availability on a Tape-On-Reel option.

Corporation

SIGNAL PROCESSING EXCELLENCE

Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the

application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others.

Sipex Corporation

Headquarters and

Sales Office

233 South Hillview Drive

Milpitas, CA 95035

TEL: (408) 934-7500

FAX: (408) 935-7600

Sales Office

22 Linnell Circle

Billerica, MA 01821

TEL: (978) 667-8700

FAX: (978) 670-9001

e-mail: sales@sipex.com