DESCRIPTION

MAX3243E

The MAX3243E device consists of three line drivers, five line receivers, and a dual charge-pump circuit with

±15-kV ESD (HBM and IEC61000-4-2, Air-Gap Discharge) and ±8-kV ESD (IEC61000-4-2, Contact Discharge)

protection on serial-port connection pins. The device meets the requirements of TIA/EIA-232-F and provides the

electrical interface between an asynchronous communication controller and the serial-port connector. This

combination of drivers and receivers matches that needed for the typical serial port used in an IBM PC/AT, or

compatible. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-V

supply. In addition, the device includes an always-active noninverting output (ROUT2B), which allows

applications using the ring indicator to transmit data while the device is powered down. The device operates at

data signaling rates up to 250 kbit/s and a maximum of 30-V/

µs driver output slew rate.

Flexible control options for power management are available when the serial port is inactive. The

auto-powerdown feature functions when FORCEON is low and FORCEOFF is high. During this mode of

operation, if the device does not sense a valid RS-232 signal, the driver outputs are disabled. If FORCEOFF is

set low, both drivers and receivers (except ROUT2B) are shut off, and the supply current is reduced to 1

µA.

Disconnecting the serial port or turning off the peripheral drivers causes the auto-powerdown condition to occur.

Auto-powerdown can be disabled when FORCEON and FORCEOFF are high, and should be done when driving

a serial mouse. With auto-powerdown enabled, the device is activated automatically when a valid signal is

applied to any receiver input. The INVALID output is used to notify the user if an RS-232 signal is present at any

receiver input. INVALID is high (valid data) if any receiver input voltage is greater than 2.7 V or less than –2.7 V

or has been between –0.3 V and 0.3 V for less than 30

µs. INVALID is low (invalid data) if all receiver input

voltages are between –0.3 V and 0.3 V for more than 30

µs. Refer to Figure 5 for receiver input levels.

The MAX3243EC is characterized for operation from 0°C to 70°C. The MAX3243EI is characterized for operation

from –40°C to 85°C.

ORDERING INFORMATION

ORDERABLE PART NUMBER

TOP-SIDE MARKING

MAX3243ECDW

SOIC – DW

Tape and reel

MAX3243EC

MAX3243ECDWR

MAX3243ECDB

SSOP – DB

Tape and reel

MAX3243EC

0°C to 70°C

MAX3243ECDBR

MAX3243ECPW

TSSOP – PW

Tape and reel

MP243EC

MAX3243ECPWR

QFN – RHB

Tape and reel

MAX3243ECRHBR

MP243E

MAX3243EIDB

SSOP – DB

Tape and reel

MAX3243EI

MAX3243EIDBR

MAX3243EIDW

SOIC – DW

Tape and reel

MAX3243EI

–40°C to 85°C

MAX3243EIDWR

MAX3243EIPW

TSSOP – PW

Tape and reel

MP243EI

MAX3243EIPWR

QFN – RHB

Tape and reel

MAX3243EIRHBR

MR243E

(1)

Package drawings, thermal data, and symbolization are available at www.ti.com/packaging.

(2)

For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI

website at www.ti.com.

2

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Product Folder Link(s): MAX3243E