Datasheet

ManualsBrandsMaxim ManualsDriversTransceiver RS232 5.5V 300uA SSOP

_______________General Description

The MAX3221/MAX3223/MAX3243 achieve 1µA supply

current with Maxim’s revolutionary AutoShutdown™ fea-

ture. When the MAX3221/MAX3223/MAX3243 do not

sense a valid signal level on their receiver inputs, the

on-board power supply and drivers shut down. This

occurs if the RS-232 cable is disconnected or if the

transmitters of the connected peripheral are turned off.

The system turns on again when a valid level is applied

to any RS-232 receiver input. As a result, the system

saves power without changes to the existing BIOS or

operating system.

The MAX3221/MAX3223/MAX3243 transceivers are 3V-

powered EIA/TIA-232 and V.28/V.24 communications

interfaces intended for notebook computer applica-

tions. A proprietary, high-efficiency, dual charge-pump

power supply and a low-dropout transmitter combine to

deliver true RS-232 performance from a single +3.0V to

+5.5V supply. A guaranteed data rate of 120kbps pro-

vides compatibility with popular software for communi-

cating with personal computers.

The MAX3221/MAX3223/MAX3243 require only 0.1µF

capacitors in 3.3V operation, and can operate from input

voltages ranging from +3.0V to +5.5V. They are ideal for

3.3V-only systems, mixed 3.3V and 5.0V systems, or

5.0V-only systems that require true RS-232 performance.

The MAX3221 is a 1-driver/1-receiver 16-pin SSOP ver-

sion of the 20-pin MAX3223 (2-driver/2-receiver). The

MAX3243 3-driver/5-receiver, complete serial port is

ideal for notebook or subnotebook computers. The

MAX3243 includes one complementary always-active

receiver. This receiver can monitor an external device

(such as a modem) in shutdown, without forward bias-

ing the protection diodes in a UART that may have V

completely removed.

____________________________Features

♦ 1µA Supply Current Achieved with AutoShutdown

♦ Small 0.1µF Capacitors

♦ True RS-232 Operation from V

= +3.0V to +5.5V

♦ Meets EIA/TIA-562 Specifications Down to 2.7V

♦ Guaranteed 120kbps Data Rate

♦ 6V/µs Min Guaranteed Slew Rate

♦ Smallest Single-Supply RS-232 Transceiver

(MAX3221)

♦ Guaranteed Mouse Driveability (MAX3243)

♦ Small TSSOP Package (MAX3223/MAX3243)

________________________Applications

Notebook, Subnotebook, and Palmtop Computers

Battery-Powered Equipment

Hand-Held Equipment

Peripherals

Printers

MAX3221/MAX3223/MAX3243*

1µA Supply-Current, True +3V to +5.5V

RS-232 Transceivers with AutoShutdown

________________________________________________________________ Maxim Integrated Products 1

19-0306; Rev 6; 3/99

PART

MAX3221CAE

MAX3221EUE†

-40°C to +85°C

0°C to +70°C

TEMP. RANGE PIN-PACKAGE

16 SSOP

16 TSSOP

* Covered by U.S. Patent numbers 4,636,930; 4,679,134; 4,777,577; 4,797,899; 4,809,152; 4,897,774; 4,999,761; and other patents pending.

†Future product—contact factory for availability.

AutoShutdown is a trademark of Maxim Integrated Products.

Pin Configurations appear at end of data sheet.

Typical Operating Circuits appear at end of data sheet.

MAX3223EPP -40°C to +85°C 20 Plastic DIP

MAX3223EAP -40°C to +85°C 20 SSOP

MAX3243CWI

0°C to +70°C 28 Wide SO

MAX3243CAI 0°C to +70°C 28 SSOP

MAX3243EWI -40°C to +85°C 28 Wide SO

MAX3243EAI -40°C to +85°C 28 SSOP

MAX3223CPP

MAX3223CAP 0°C to +70°C

0°C to +70°C 20 Plastic DIP

20 SSOP

______________Ordering Information

_____________________Selector Guide

MAX3221

MAX3223

MAX3243

3.0 to 5.5

3.0 to 5.55

Yes

PART Tx Rx V

RANGE (V) AutoShutdown

MAX3221CUE†

0°C to +70°C 16 TSSOP

MAX3221EAE -40°C to +85°C 16 SSOP

MAX3223CUP 0°C to +70°C 20 TSSOP

MAX3223EUP -40°C to +85°C 20 TSSOP

MAX3243CUI 0°C to +70°C 28 TSSOP

MAX3243EUI -40°C to +85°C 28 TSSOP

For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.

For small orders, phone 1-800-835-8769.

Summary of content (16 pages)

PAGE 1
9-0306; Rev 6; 3/99 1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown The MAX3221/MAX3223/MAX3243 require only 0.1µF capacitors in 3.3V operation, and can operate from input voltages ranging from +3.0V to +5.5V. They are ideal for 3.3V-only systems, mixed 3.3V and 5.0V systems, or 5.0V-only systems that require true RS-232 performance. The MAX3221 is a 1-driver/1-receiver 16-pin SSOP version of the 20-pin MAX3223 (2-driver/2-receiver).
PAGE 2
MAX3221/MAX3223/MAX3243 1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown ABSOLUTE MAXIMUM RATINGS 16-Pin SSOP (derate 7.14mW/°C above +70°C) ...........571mW 16-Pin TSSOP (derate 6.70mW/°C above +70°C) .........533mW 20-Pin Plastic DIP (derate 11.11mW/°C above +70°C)....889mW 20-Pin SSOP (derate 8.00mW/°C above +70°C) ...........640mW 20-Pin TSSOP DIP (derate 7.00mW/°C above +70°C).....559mW 28-Pin Wide SO (derate 12.50mW/°C above +70°C) ............1W 28-Pin SSOP (derate 9.
PAGE 3
1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown (VCC = +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER CONDITIONS MIN TYP MAX UNITS 25 V RECEIVER INPUTS Input Voltage Range -25 Input Threshold Low TA = +25°C Input Threshold High TA = +25°C VCC = 3.3V 0.6 1.2 VCC = 5.0V 0.8 1.5 V VCC = 3.3V 1.5 2.4 VCC = 5.0V 1.8 2.4 Input Hysteresis 0.
PAGE 4
__________________________________________Typical Operating Characteristics (VCC = +3.3V, 235kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ, TA = +25°C, unless otherwise noted.) 20 18 SLEW RATE (V/µs) 4 3 2 1 0 -1 -2 -3 MAX3221/3223-02 VOUT+ 16 14 -SLEW 12 10 +SLEW 8 6 -4 4 VOUT- FOR DATA RATES UP TO 235kbps 35 35 30 235kbps 30 25 25 20 120kbps 20 15 15 10 20kbps 10 5 2 1000 2000 3000 4000 4000 MAX3243 TRANSMITTER OUTPUT VOLTAGE vs.
PAGE 5
1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown PIN NAME FUNCTION — EN Receiver Enable Control. Drive low for normal operation. Drive high to force the receiver outputs into a high-Z state.
PAGE 6
MAX3221/MAX3223/MAX3243 1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown POWER MANAGEMENT UNIT OR KEYBOARD CONTROLLER FORCEOFF VCC FORCEON INVALID PROTECTION DIODE PREVIOUS RS-232 MAX3243 VCC I Rx 5k UART Tx CPU I/O CHIP WITH UART GND SHDN = GND RS-232 (a) OLDER RS-232: POWERED-DOWN UART DRAWS CURRENT FROM ACTIVE RECEIVER OUTPUT IN SHUTDOWN. VCC TO µP LOGIC TRANSITION DETECTOR Figure 1.
PAGE 7
1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown FORCEOFF EN T_OUT R_OUT 0 0 High-Z Active 0 1 High-Z 1 0 Active* High-Z Active 1 1 Active* High-Z MAX3221/MAX3223/MAX3243 Table 1a. MAX3221/MAX3223 FORCEOFF and Enable Control Truth Table +0.3V R_IN 30µs COUNTER R -0.3V TO MAX32_ _ POWER SUPPLY AND TRANSMITTERS INVALID * TRANSMITTERS ARE DISABLED, REDUCING SUPPLY CURRENT TO 1µA IF ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR AT LEAST 30µs.
PAGE 8
Table 2. AutoShutdown Logic RS-232 SIGNAL PRESENT AT RECEIVER INPUT FORCEOFF INPUT Yes No FORCEON INPUT INVALID OUTPUT H X H Normal Operation H H L Normal Operation (Forced On) TRANSCEIVER STATUS No H L L Shutdown (AutoShutdown) Yes L X H Shutdown (Forced Off) No L X L Shutdown (Forced Off) other system to realize that the MAX3221/MAX3223/ MAX3243 is awake. If the other system outputs valid RS-232 signals within that time, the RS-232 ports on both systems remain enabled.
PAGE 9
2V/div T1 50µs/div 4 3 T1 0 -1 T2 VOUT+ -2 -3 VCC VOUT- T3 VOUT- -4 -5 -6 0 VCC = +3.3V C1–C4 = 0.1µF VOUT+ VCC = 3.0V 2 1 MAX3222-04 T2 6 5 1 2 3 4 5 6 7 LOAD CURRENT PER TRANSMITTER (mA) Figure 6. Transmitter Outputs when Exiting Shutdown or Powering Up Power-Supply Decoupling In most circumstances a 0.1µF bypass capacitor is adequate.
PAGE 10
MAX3221/MAX3223/MAX3243 1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown +3.3V 26 0.1µF 28 C1 0.1µF 24 1 C2 0.1µF 2 LOGIC INPUTS VCC 27 C1+ V+ C3 0.1µF C1C2+ COMPUTER SERIAL PORT 3 MAX3243 V- C4 0.
PAGE 11
1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown VCC (V) 0.1µF VCC C1+ V+ C3 C1 C1 (µF) C2, C3, C4 (µF) 3.0 to 3.6 0.1 0.1 4.5 to 5.5 0.047 0.33 3.0 to 5.5 0.1 0.47 C1C2+ MAX3221 MAX3223 MAX3243 C2 C2- R_ IN R_ OUT VCC C4 T_ OUT T_ IN 0V V- EN (MAX3221/3) FORCEOFF 5k Table 4. Logic Family Compatibility with Various Supply Voltages SYSTEM POWERSUPPLY VOLTAGE (V) VCC SUPPLY VOLTAGE (V) 3.3 3.3 5 5 5 3.
PAGE 12
MAX3221/MAX3223/MAX3243 1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown __________________________________________________Typical Operating Circuits +3.3V 15 0.1µF C5 2 C1+ C1 0.1µF 4 C15 C2 0.1µF 6 VCC 3 V+ MAX3221 C2+ V- C3 0.1µF 28 C1+ C1 0.1µF T1OUT 13 24 1 C2 0.
PAGE 13
1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown PART POWERSUPPLY VOLTAGE (V) No. OF TRANSMITTERS/ RECEIVERS No. OF RECEIVERS ACTIVE IN SHUTDOWN GUARANTEED DATA RATE (kbps) EIA/TIA232 OR 562 MAX212 3.0 to 3.6 3/5 5 120 232 Drives mice MAX218 1.8 to 4.25 2/2 2 120 232 Operates directly from batteries without a voltage regulator MAX562 MAX563 2.7 to 5.25 3.0 to 3.6 3/5 2/2 5 2 230 120 562 562 230kbps guaranteed data rate 0.1µF capacitors MAX3212 2.
PAGE 14
MAX3221/MAX3223/MAX3243 1µA Supply-Current, True +3V to +5.
PAGE 15
1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown TSSOP.EPS SSOP.
PAGE 16
SOICW.EPS ___________________________________________Package Information (continued) PDIPN.EPS MAX3221/MAX3223/MAX3243 1µA Supply-Current, True +3V to +5.5V RS-232 Transceivers with AutoShutdown Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.