1

LT1330

5V RS232 Transceiver with

3V Logic Interface and One

Receiver Active in Shutdown

R

1330 TA02

S

APPLICATI

Output Waveforms

RECEIVER

OUTPUT

DRIVER

OUTPUT

s

Notebook Computers

s

Palmtop Computers

APPLICATI

TYPICAL

INPUT

s

3V Logic Interface

s

ESD Protection over

±10kV

s

Uses Small Capacitors: 0.1

µF, 0.2µF, 1.0µF

s

One Low Power Receiver Remains Active While in

Shutdown

s

Pin Compatible with LT1137A and LT1237

s

s

s

CMOS Comparable Low Power: 30mW

s

Easy PC Layout—Flowthrough Architecture

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Rugged Bipolar Design

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Outputs Assume a High Impedance State When Off

or Powered Down

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Absolutely No Latchup

s

60

µA Supply Current in Shutdown

s

Available in SO and SSOP Packages

DESCRIPTIO

S

FEATURE

, LTC and LT are registered trademarks of Linear Technology Corporation.

The LT

ceiver with low supply current. Designed to interface with

new 3V logic, the LT1330 operates with both a 5V power

supply and a 3V logic power supply. The chip may be shut

down to micropower operation with one receiver remain-

ing active to monitor RS232 inputs such as ring detect

from a modem.

The LT1330 is fully compliant with all EIA RS232 specifi-

cations. Additionally, the RS232 line input and output pins

are resilient to multiple

±10kV ESD strikes. This eliminates

the need for costly TransZorbs

part.

The LT1330 operates to 120kbaud even driving high

capacitive loads. During shutdown, driver and receiver

outputs are at a high impedance state allowing devices to

be paralleled.

TransZorb is a registered trademark of General Instruments, GSI

1330 TA01

1.0

µF

2

× 0.1µF

0.1

µF

TO

LINE

LT1330

1

2

3

4

5

6

7

8

9

10

11

12

13

14

DRIVER 1 OUT

RX1 IN

DRIVER 2 OUT

RX2 IN

RX3 IN

RX4 IN

DRIVER 3 OUT

RX5 IN (LOW-Q)

ON/OFF

28

27

26

25

24

23

22

21

20

19

18

17

16

15

2

× 0.1µF

DRIVER 1 IN

RX1 OUT

DRIVER 2 IN

RX2 OUT

RX3 OUT

RX4 OUT

DRIVER 3 IN

RX5 OUT (LOW-Q)

GND

DRIVER

DISABLE

RING DETECT IN

SHUTDOWN

CONTROL OUT

µCONTROLLER OR

µPROCESSOR

TO LOGIC