SP3232EBCN-L/TR - Exar

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

SP3222EB/SP3232EB

True +3.0V to +5.5V RS-232 Transceivers

The SP3222EB/SP3232EB series is an RS-232 transceiver solution intended for portable or

hand-held applications such as notebook or laptop computers. The SP3222EB/SP3232EB

series has a high-efciency, charge-pump power supply that requires only 0.1µF capacitors

in 3.3V operation. This charge pump allows the SP3222EB/SP3232EB series to deliver true

RS-232 performance from a single power supply ranging from +3.0V to +5.5V. The SP3222EB/

SP3232EB are 2-driver/2-receiver devices. The ESD tolerance of the SP3222EB/SP3232EB

devices is over +/-15kV for both Human Body Model and IEC61000-4-2 Air discharge test

methods. The SP3222EB device has a low-power shutdown mode where the devices' driver

outputs and charge pumps are disabled. During shutdown, the supply current falls to less

than 1µA.

FEATURES

■ Meets true EIA/TIA-232-F Standards

from a +3.0V to +5.5V power supply

■ 250kbps Transmission Rate Under Load

■ 1µA Low Power Shutdown with

Receivers active (SP3222EB)

■ Interoperable with RS-232 down to a

+2.7V power source

■ Enhanced ESD Specications:

+15kV Human Body Model

+15kV IEC61000-4-2 Air Discharge

+8kV IEC61000-4-2 Contact Discharge

DESCRIPTION

SELECTION TABLE

Now Available in Lead Free Packaging

V-

413

C1+

V+

C1-

C2+

C2-

R1IN

R2IN

GND

T1OUT

T2IN

SP3232EB

T1IN

R1OUT

R2OUT

T2OUT

Device Power

Supplies

RS-232

Drivers

RS-232

Receivers

External

Components

Shutdown TTL

3-State

# of

Pins

SP3222EB +3.0V to

+5.5V

2 2 4 Capacitors Yes Yes 18, 20

SP3232EB +3.0V to

+5.5V

2 2 4 Capacitors No No 16

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

NOTE 1: V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.

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 and cause permanent damage to the

device.

VCC.......................................................-0.3V to +6.0V

V+ (NOTE 1).......................................-0.3V to +7.0V

V- (NOTE 1)........................................+0.3V to -7.0V

V+ + |V-| (NOTE 1)...........................................+13V

ICC (DC VCC or GND current).........................+100mA

Input Voltages

TxIN, EN..............................................-0.3V to +6.0V

RxIN...................................................................+25V

Output Voltages

TxOUT.............................................................+13.2V

RxOUT, .......................................-0.3V to (VCC +0.3V)

Short-Circuit Duration

TxOUT....................................................Continuous

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

Unless otherwise noted, the following specications apply for VCC = +3.0V to +5.5V with TAMB = TMIN to TMAX,

C1 - C4 = 0.1µF.

Power Dissipation per package

20-pin SSOP (derate 9.25mW/oC above +70oC)..............750mW

18-pin SOIC (derate 15.7mW/oC above +70oC)..............1260mW

20-pin TSSOP (derate 11.1mW/oC above +70oC).............890mW

16-pin SSOP (derate 9.69mW/oC above +70oC)...............775mW

16-pin Wide SOIC (derate 11.2mW/oC above +70oC)........900mW

16-pin TSSOP (derate 10.5mW/oC above +70oC)..............850mW

16-pin nSOIC (derate 13.57mW/oC above +70oC)...........1086mW

ELECTRICAL CHARACTERISTICS

PARAMETER MIN. TYP. MAX. UNITS CONDITIONS

DC CHARACTERISTICS

Supply Current 0.3 1.0 mA no load, VCC = 3.3V,

TAMB = 25oC, TxIN = GND or VCC

Shutdown Supply Current 1.0 10 µA SHDN = GND, VCC = 3.3V,

TAMB = 25oC, TxIN = Vcc or GND

LOGIC INPUTS AND RECEIVER OUTPUTS

Input Logic Threshold LOW GND 0.8 V TxIN, EN, SHDN, Note 2

Input Logic Threshold HIGH 2.0 Vcc V Vcc = 3.3V, Note 2

Input Logic Threshold HIGH 2.4 Vcc V Vcc = 5.0V, Note 2

Input Leakage Current +0.01 +1.0 µA TxIN, EN, SHDN,

TAMB = +25oC, VIN = 0V to VCC

Output Leakage Current +0.05 +10 µA Receivers disabled, VOUT = 0V to VCC

Output Voltage LOW 0.4 V IOUT = 1.6mA

Output Voltage HIGH VCC -0.6 VCC -0.1 V IOUT = -1.0mA

DRIVER OUTPUTS

Output Voltage Swing +5.0 +5.4 V All driver outputs loaded with 3KΩ to

GND, TAMB = +25oC

NOTE 2: Driver Input hysteresis is typically 250mV.

ABSOLUTE MAXIMUM RATINGS

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

Unless otherwise noted, the following specications apply for VCC = +3.0V to +5.5V with TAMB = TMIN to TMAX,

C1 - C4 = 0.1µF. Typical values apply at VCC = +3.3V or +5.0V and TAMB = 25°C.

ELECTRICAL CHARACTERISTICS

PARAMETER MIN. TYP. MAX. UNITS CONDITIONS

DRIVER OUTPUTS (continued)

Output Resistance 300 ΩVCC = V+ = V- = 0V, VOUT=+2V

Output Short-Circuit Current +35 +60 mA VOUT = 0V

Output Leakage Current +25 µA VCC = 0V or 3.0V to 5.5V, VOUT =

+12V, Drivers disabled

RECEIVER INPUTS

Input Voltage Range -25 25 V

Input Threshold LOW 0.6 1.2 V Vcc = 3.3V

Input Threshold LOW 0.8 1.5 V Vcc = 5.0V

Input Threshold HIGH 1.5 2.4 V Vcc = 3.3V

Input Threshold HIGH 1.8 2.4 V Vcc = 5.0V

Input Hysteresis 0.3 V

Input Resistance 3 5 7 kΩ

TIMING CHARACTERISTICS

Maximum Data Rate 250 Kbps RL = 3KΩ, CL = 1000pF, one

driver active

Receiver Propagation Delay, tPHL

0.15 µs Receiver input to Receiver

output, CL = 150pF

Receiver Propagation Delay, tPLH 0.15 µs Receiver input to Receiver

output, CL = 150pF

Receiver Output Enable Time 200 ns

Receiver Output Disable Time 200 ns

Driver Skew 100 ns | tPHL - tPLH |, TAMB = 25°C

Receiver Skew 50 ns | tPHL - tPLH |

Transition-Region Slew Rate 30 V/µs Vcc = 3.3V, RL = 3kΩ, TAMB =

25°C, measurements taken from

-3.0V to +3.0V or +3.0V to -3.0V

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

Unless otherwise noted, the following performance characteristics apply for VCC = +3.3V, 1000kbps data rate, all

drivers loaded with 3kΩ, 0.1µF charge pump capacitors, and TAMB = +25°C.

Figure 2. Slew Rate vs Load Capacitance

Figure 1. Transmitter Output Voltage vs Load

Capacitance

-2

-4

-6 0 1000 2000 3000 4000 5000

TxOUT +

TxOUT -

Transmitter Output

Voltage (V)

Load Capacitance (pF)

T1 at 250Kbps

T2 at 15.6Kbps

All TX loaded 3K // CLoad

Figure 3. Supply Current VS. Load Capacitance

when Transmitting Data

Figure 5. Transmitter Output Voltage vs Supply

Voltage

Figure 4. Supply Current VS. Supply Voltage

TYPICAL PERFORMANCE CHARACTERISTICS

00 500 1000 2000 3000 4000 5000

Slew rate (V/µs)

Load Capacitance (pF)

- Slew

+ Slew

T1 at 250Kbps

T2 at 15.6Kbps

All TX loaded 3K // CLoad

-2

-4

-6 2.7 3 3.5 4 4.5 5

Supply Voltage (V)

Transmitter Output

Voltage (V)

TxOUT -

TxOUT +

T1 at 250Kbps

T2 at 15.6Kbps

All TX loaded 3K // 1000 pF

Supply Current (mA)

Load Capacitance (pF)

0 1000 2000 3000 4000 5000

250Kbps

125Kbps

20Kbps

T1 at Full Data Rate

T2 at 1/16 Data Rate

All TX loaded 3K // CLoad

02.7 3 3.5 4 4.5 5

Supply Current (mA)

Supply Voltage (V)

1 Transmitter at 250Kbps

1 Transmitter at 15.6Kbps

All transmitters loaded with 3K // 1000pf

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

Table 1. Device Pin Description

NAME FUNCTION

PIN NUMBER

SP3222EB SP3232EB

SOIC SSOP

TSSOP

EN Receiver Enable. Apply Logic LOW for normal operation.

Apply logic HIGH to disable the receiver outputs (high-Z state) 1 1 -

C1+ Positive terminal of the voltage doubler charge-pump capacitor 2 2 1

V+ +5.5V output generated by the charge pump 3 3 2

C1- Negative terminal of the voltage doubler charge-pump capacitor 4 4 3

C2+ Positive terminal of the inverting charge-pump capacitor 5 5 4

C2- Negative terminal of the inverting charge-pump capacitor 6 6 5

V- -5.5V output generated by the charge pump 7 7 6

T1OUT RS-232 driver output. 15 17 14

T2OUT RS-232 driver output. 8 8 7

R1IN RS-232 receiver input 14 16 13

R2IN RS-232 receiver input 9 9 8

R1OUT TTL/CMOS receiver output 13 15 12

R2OUT TTL/CMOS receiver output 10 10 9

T1IN TTL/CMOS driver input 12 13 11

T2IN TTL/CMOS driver input 11 12 10

GND Ground. 16 18 15

VCC +3.0V to +5.5V supply voltage 17 19 16

SHDN

Shutdown Control Input. Drive HIGH for normal device operation.

Drive LOW to shutdown the drivers (high-Z output) and the on-

board power supply

18 20 -

N.C. No Connect - 11, 14 -

PIN FUNCTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

Figure 7. Pinout Conguration for the SP3232EB

Figure 6. Pinout Congurations for the SP3222EB

V-

417

SHDN

C1+

V+

C1-

C2+

C2-

N.C.

R1IN

GND

T1OUT

N.C.

10 11

R2IN

R2OUT

SP3222EB

T2OUT T1IN

T2IN

R1OUT

SSOP/TSSOP

V-

415

SHDN

C1+

V+

C1-

C2+

C2-

R1IN

GND

T1OUT

910

R2IN

SP3222EB

T2OUT T2IN

T1IN

R1OUT

nSOIC

R2OUT

V-

413

C1+

V+

C1-

C2+

C2-

R1IN

R2IN

GND

T1OUT

T2IN

SP3232EB

T1IN

R1OUT

R2OUT

T2OUT

PINOUT

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

Figure 8. SP3222EB Typical Operating Circuits

SP3222EB

GND

T1IN

T2IN

T1OUT

T2OUT

C1+

C1-

C2+

C2-

V+

V-

0.1µF

0.1µ F

0.1µF

*C3

0.1µF

RS-232

OUTPUTS

RS-232

INPUTS

LOGIC

INPUTS

5kΩ

R1IN

R1OUT

5kΩ

R2IN

R2OUT

LOGIC

OUTPUTS

EN 20

SHDN

*can be returned to

either V

or GND

SSOP

TSSOP

SP3222EB

GND

T1IN

T2IN

T1OUT

T2OUT

C1+

C1-

C2+

C2-

V+

V-

0.1µF

*C3

0.1µF

RS-232

OUTPUTS

RS-232

INPUTS

LOGIC

INPUTS

5kΩ

R1IN

R1OUT

5kΩ

R2IN

R2OUT

LOGIC

OUTPUTS

EN 18

SHDN

*can be returned to

either V

or GND

nSOIC

Figure 9. SP3232EB Typical Operating Circuit

SP3232EB

GND

T1IN

T2IN

T1OUT

T2OUT

C1+

C1-

C2+

C2-

V+

V-

0.1µF

+*C3

7RS-232

OUTPUTS

RS-232

INPUTS

LOGIC

INPUTS

5kΩ

R1IN

R1OUT

12 13

5kΩ

R2IN

R2OUT

LOGIC

OUTPUTS

*can be returned to

either V

or GND

0.1µF

TYPICAL OPERATING CIRCUITS

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

The SP3222EB/SP3232EB transceivers

meet the EIA/TIA-232 and ITU-T V.28/V.24

communication protocols and can be imple-

mented in battery-powered, portable, or

hand-held applications such as notebook

or palmtop computers. The SP3222EB/

SP3232EB devices feature Exar's propri-

etary on-board charge pump circuitry that

generates ±5.5V for RS-232 voltage levels

from a single +3.0V to +5.5V power supply.

This series is ideal for +3.3V-only systems,

mixed +3.3V to +5.5V systems, or +5.0V-only

systems that require true RS-232 perfor-

mance. The SP3222EB/SP3232EB devices

can operate at a data rate of 250kbps when

fully loaded.

The SP3222EB and SP3232EB are 2-

driver/2- receiver devices ideal for portable

or hand-held applications. The SP3222EB

features a 1µA shutdown mode that reduces

power consumption and extends battery life

in portable systems. Its receivers remain

active in shutdown mode, allowing external

devices such as modems to be monitored

using only 1µA supply current.

THEORY OF OPERATION

The SP3222EB/SP3232EB series is made

up of three basic circuit blocks:

1. Drivers

2. Receivers

3. The Exar proprietary charge pump

Drivers

The drivers are inverting level transmitters

that convert TTL or CMOS logic levels to

+5.0V EIA/TIA-232 levels with an inverted

sense relative to the input logic levels.

Typically, the RS-232 output voltage swing

is +5.4V with no load and +5V minimum fully

loaded. The driver outputs are protected

against innite short-circuits to ground with-

out degradation in reliability. Driver outputs

will meet EIA/TIA-562 levels of +/-3.7V with

supply voltages as low as 2.7V.

The drivers can guarantee a data rate of

250kbps fully loaded with 3kΩ in parallel

with 1000pF, ensuring compatability with

PC-to-PC communication software.

The slew rate of the driver is internally limited

to a maximum of 30V/µs in order to meet the

EIA standards (EIA RS-232D 2.1.7, Para-

graph 5). The transition of the loaded output

from HIGH to LOW also meet the monotonic-

ity requirements of the standard.

Figure 10 shows a loopback test circuit

used to test the RS-232 Drivers. Figure

11 shows the test results of the loopback

circuit with all drivers active at 120kbps

with RS-232 loads in parallel with a

1000pF capacitor. Figure 12 shows the

test results where one driver was active

at 250kbps and all drivers loaded with an

RS-232 receiver in parallel with 1000pF

capacitors. A solid RS-232 data transmis-

sion rate of 250kbps provides compatibility

with many designs in personal computer

peripherals and LAN applications.

The SP3222EB driver's output stages are

turned off (tri-state) when the device is in

shutdown mode. When the power is off, the

SP3222EB device permits the outputs to be

driven up to +/-12V. The driver's inputs do

not have pull-up resistors. Designers should

connect unused inputs to Vcc or GND.

In the shutdown mode, the supply current

falls to less than 1µA, where SHDN = LOW.

When the SP3222EB device is shut down,

the device's driver outputs are disabled (tri-

stated) and the charge pumps are turned off

with V+ pulled down to Vcc and V- pulled to

GND. The time required to exit shutdown is

typically 100µs. Connect SHDN to Vcc if the

shutdown mode is not used.

DESCRIPTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

Receivers

The Receivers convert EIA/TIA-232 levels

to TTL or CMOS logic output levels. The

SP3222EB receivers have an inverting

tri-state output. These receiver outputs

(RxOUT) are tri-stated when the enable

control EN = HIGH. In the shutdown mode,

the receivers can be active or inactive. EN

has no effect on TxOUT. The truth table logic

of the SP3222EB driver and receiver outputs

can be found in Table 2.

Since receiver input is usually from a trans-

mission line where long cable lengths and

system interference can degrade the signal,

the inputs have a typical hysteresis margin

of 300mV. This ensures that the receiver

is virtually immune to noisy transmission

lines. Should an input be left unconnected,

an internal 5KΩ pulldown resistor to ground

will commit the output of the receiver to a

HIGH state.

Table 2. SP3222EB Truth Table Logic for Shutdown

and Enable Control

Figure 10. SP3222EB/SP3232EB Driver Loopback

Test Circuit

Charge Pump

The charge pump is an Exar-patended

design (U.S. 5,306,954) and uses a unique

approach compared to older less-efcient

designs. The charge pump still requires four

external capacitors, but uses a four-phase

voltage shifting technique to attain sym-

metrical 5.5V power supplies. The internal

power supply consists of a regulated dual

charge pump that provides output voltages

of +/-5.5V regardless of the input voltage

(Vcc) over the +3.0V to +5.5V range.

Figure 12. Loopback Test results at 250Kbps

Figure 11. Loopback Test results at 120kbps

SP3222EB

SP3232EB

GND

TxIN TxOUT

C1+

C1-

C2+

C2-

V+

V-

0.1µF

LOGIC

INPUTS

5kΩ

RxIN

RxOUT

LOGIC

OUTPUTS

EN* *SHDN

1000pF

* SP3222EB only

SHDN EN TxOUT RxOUT

0 0 Tri-state Active

0 1 Tri-state Tri-state

1 0 Active Active

1 1 Active Tri-state

DESCRIPTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

In most circumstances, decoupling the power

supply can be achieved adequately using

a 0.1µF bypass capacitor at C5 (refer to

gures 8 and 9)

In applications that are sensitive to power-

supply noise, decouple Vcc to ground with a

capacitor of the same value as charge-pump

capacitor C1. Physically connect bypass

capcitors as close to the IC as possible.

The charge pump operates in a discontinu-

ous mode using an internal oscillator. If the

output voltages are less than a magnitude

of 5.5V, the charge pump is enabled. If the

output voltages exceed a magnitude of 5.5V,

the charge pump is disabled. This oscillator

controls the four phases of the voltage shift-

ing. A description of each phase follows.

Phase 1

— VSS charge storage — During this phase

of the clock cycle, the positive side of capaci-

tors C1 and C2 are initially charged to VCC.

+ is then switched to GND and the charge

in C1

– is transferred to C2

–. Since C2

+ is con-

nected to VCC, the voltage potential across

capacitor C2 is now 2 times VCC.

Phase 2

— VSS transfer — Phase two of the clock

connects the negative terminal of C2 to the VSS

storage capacitor and the positive terminal of

C2 to GND. This transfers a negative gener-

ated voltage to C3. This generated voltage is

regulated to a minimum voltage of -5.5V.

Simultaneous with the transfer of the volt-

age to C3, the positive side of capacitor C1

is switched to VCC and the negative side is

connected to GND.

Phase 3

— VDD charge storage — The third phase of

the clock is identical to the rst phase — the

charge transferred in C1 produces –VCC in

the negative terminal of C1, which is applied

to the negative side of capacitor C2. Since

+ is at VCC, the voltage potential across C2

is 2 times VCC.

Phase 4

— VDD transfer — The fourth phase of

the clock connects the negative terminal

of C2 to GND, and transfers this positive

generated voltage across C2 to C4, the

VDD storage capacitor. This voltage is

regulated to +5.5V. At this voltage, the in-

ternal oscillator is disabled. Simultaneous

with the transfer of the voltage to C4, the

positive side of capacitor C1 is switched

to VCC and the negative side is con-

nected to GND, allowing the charge

pump cycle to begin again. The charge

pump cycle will continue as long as the

operational conditions for the internal

oscillator are present.

Since both V+ and V– are separately gener-

ated from VCC, in a no–load condition V+

and V– will be symmetrical. Older charge

pump approaches that generate V– from

V+ will show a decrease in the magnitude

of V– compared to V+ due to the inherent

inefciencies in the design.

The clock rate for the charge pump typically

operates at greater than 250kHz. The exter-

nal capacitors can be as low as 0.1µF with

a 16V breakdown voltage rating.

DESCRIPTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

Figure 14. Charge Pump — Phase 2

= +5V

Storage Capacitor

Storage Capacito

+ +

–

––

-5.5V

VCC = +5V

–5V –5V

+5V

VSS Storage Capacitor

VDD Storage Capacitor

C1C2

+ +

–

––

Figure 13. Charge Pump — Phase 1

Figure 16. Charge Pump — Phase 3

= +5V

–5V –5V

+5V

Storage Capacitor

+ +

–

––

Figure 17. Charge Pump — Phase 4

= +5V

Storage Capacitor

Storage Capacito

+ +

–

––

+5.5V

Figure 15. Charge Pump Waveforms

Ch1 2.00V Ch2 2.00V M 1.00ms Ch1 5.48V

T[ ]

+6V

a) C

b) C

GND

-6V

DESCRIPTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

ESD TOLERANCE

The SP3222EB/SP3232EB series incor-

porates 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 nor 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

The Human Body Model has been the

generally accepted ESD testing method

for semi-conductors. 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 18. This method will test the IC’s

capability to withstand an ESD transient

during normal handling such as in manu-

facturing 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 guarantee a certain amount of ESD

protection since the system itself is exposed

to the outside environment and human pres-

ence. 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 19.

There are two methods within IEC61000-4-2,

the Air Discharge method and the Contact

Discharge method.

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

Figure 18. ESD Test Circuit for Human Body Model

Device

Under

Test

DC Power

Source

SW1 SW2

DESCRIPTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

DEVICE PIN HUMAN BODY IEC61000-4-2

TESTED MODEL Air Discharge Direct Contact Level

Driver Outputs +15kV +15kV +8kV 4

Receiver Inputs +15kV +15kV +8kV 4

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 models in Figures 18 and 19 rep-

resent 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. 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-61000-4-2, the current limiting resistor

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

an 150pF, respectively.

Figure 20. ESD Test Waveform for IEC61000-4-2

Figure 19. ESD Test Circuit for IEC61000-4-2

Table 3. Transceiver ESD Tolerance Levels

and

add up to 330Ω for IEC61000-4-2.

Device

Under

Test

DC Power

Source

SW1 SW2

Contact-Discharge Model

t = 0ns t = 30ns

15A

30A

I →

t →

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.

DESCRIPTION

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

PACKAGE: 20 PIN SSOP

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

PACKAGE: 16 PIN SSOP

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

PACKAGE: 16 PIN WSOIC

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

PACKAGE: 18 PIN WSOIC

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

PACKAGE: 16 PIN nSOIC

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

PACKAGE: 16 PIN TSSOP

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

PACKAGE: 20 PIN TSSOP

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

ORDERING INFORMATION

Note: "/TR" is for tape and Reel option. "-L" is for lead free packaging

Part Number Temp. Range Package

SP3222EBCA-L 0°C to +70°C 20 Pin SSOP

SP3222EBCA-L/TR 0°C to +70°C 20 Pin SSOP

SP3222EBCT-L 0°C to +70°C 18 Pin WSOIC

SP3222EBCT-L/TR 0°C to +70°C 18 Pin WSOIC

SP3222EBCY-L 0°C to +70°C 20 Pin TSSOP

SP3222EBCY-L/TR 0°C to +70°C 20 Pin TSSOP

SP3222EBEA-L -40°C to +85°C 20 Pin SSOP

SP3222EBEA-L/TR -40°C to +85°C 20 Pin SSOP

SP3222EBET-L -40°C to +85°C 18 Pin WSOIC

SP3222EBET-L/TR -40°C to +85°C 18 Pin WSOIC

SP3222EBEY-L -40°C to +85°C 20 Pin TSSOP

SP3222EBEY-L/TR -40°C to +85°C 20 Pin TSSOP

Part Number Temp. Range Package

SP3232EBCA-L 0°C to +70°C 16 Pin SSOP

SP3232EBCA-L/TR 0°C to +70°C 16 Pin SSOP

SP3232EBCN-L 0°C to +70°C 16 Pin NSOIC

SP3232EBCN-L/TR 0°C to +70°C 16 Pin NSOIC

SP3232EBCT-L 0°C to +70°C 16 Pin WSOIC

SP3232EBCT-L/TR 0°C to +70°C 16 Pin WSOIC

SP3232EBCY-L 0°C to +70°C 16 Pin TSSOP

SP3232EBCY-L/TR 0°C to +70°C 16 Pin TSSOP

SP3232EBEA-L -40°C to +85°C 16 Pin SSOP

SP3232EBEA-L/TR -40°C to +85°C 16 Pin SSOP

SP3232EBEN-L -40°C to +85°C 16 Pin NSOIC

SP3232EBEN-L/TR -40°C to +85°C 16 Pin NSOIC

SP3232EBET-L -40°C to +85°C 16 Pin WSOIC

SP3232EBET-L/TR -40°C to +85°C 16 Pin WSOIC

SP3232EBEY-L -40°C to +85°C 16 Pin TSSOP

SP3232EBEY-L/TR -40°C to +85°C 16 Pin TSSOP

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3222EB/SP3232EB_101_060711

REVISION HISTORY

Notice

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

ability. 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 June 2011

Send your serial transceiver technical inquiry with technical details to: serialtechsupport@exar.com

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

DATE REVISION DESCRIPTION

11/02/05 -- Legacy Sipex Datasheet

09/09/09 1.0.0 Convert to Exar Format, Update ordering information and

change revision to 1.0.0.

06/07/11 1.0.1 Remove obsolete devices per PDN 110510-01 and change

ESD rating to IEC-61000-4-2.