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

SP3249E_100_013111

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SP3249E

Intelligent +3.0V to +5.5V RS-232 Transceiver

The SP3249E device is an RS-232 transceiver solution intended for portable or hand-held applications

such as notebook and palmtop computers. The SP3249E uses an internal high-efficiency, charge-pump

power supply that requires only 0.1µF capacitors in 3.3V operation. This charge pump and Exar's

driver architecture allow the SP3249E device to deliver compliant RS-232 performance from a single

power supply ranging from +3.0V to +5.5V. The SP3249E is a 5-driver / 3-receiver device that is ideal

for laptop / notebook computer and PDA applications.

FEATURES

■ Meets true EIA/TIA-232-F Standards

from a +3.0V to +5.5V power supply

■ Interoperable with EIA/TIA-232 and

adheres to EIA/TIA-562 down to a +2.7V

power source

■ Minimum 250Kbps data rate under load

■ Regulated Charge Pump Yields Stable

RS-232 Outputs Regardless of V

CC

Variations

■ Enhanced ESD Specifications:

+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

T4IN

1

2

3

4

21

22

23

24

5

6

7

20

19

18

C2-

V-

R1IN

R2IN

IN

C2+

C1-

GND

V+

T1IN

8

9

10

11

14

15

16

17

12

13

T OUT

T2OUT

T3OUT

T3IN

T2IN

T5IN

R3OUT

R2OUT

R1OUT

SP3249E

C1+

T4OUT

T5OUT

1

3

R

Device

Power

Supplies

RS-232

Drivers

RS-232

Receivers

External

Components

Auto

On-Line

Circuitry

TTL 3-State

# of

Pins

SP3223E

+3.0V to +5.5V

2

2

4 Capacitors

YES

YES

20

SP3243E

+3.0V to +5.5V

3

5

4 Capacitors

YES

YES

28

SP3238E

+3.0V to +5.5V

5

3

4 Capacitors

YES

YES

28

SP3239E

+3.0V to +5.5V

5

3

4 Capacitors

NO

YES

28

SP3249E

+3.0V to +5.5V

5

3

4 Capacitors

NO

NO

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