Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsInterface ICsInterface IC - transceivers RS232 3/5 SOIC 28 W

AVAILABLE

Functional Diagrams

Pin Configurations appear at end of data sheet.

Functional Diagrams continued at end of data sheet.

UCSP is a trademark of Maxim Integrated Products, Inc.

For pricing, delivery, and

ordering information, please contact Maxim Direct

at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.

1µA Supply Current, 1Mbps, 3.0V to 5.5V,

RS-232 Transceivers with AutoShutdown Plus

AutoShutdown Plus, MegaBaud, and UCSP are trademarks

of Maxim Integrated Products, Inc.

________________General Description

The MAX3224–MAX3227/MAX3244/MAX3245 are 3V-

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

interfaces with automatic shutdown/wakeup features

and high data-rate capabilities.

All devices achieve a 1µA supply current using Maxim’s

revolutionary AutoShutdown Plus™ feature. These

devices automatically enter a low-power shutdown

mode when the RS-232 cable is disconnected or the

transmitters of the connected peripherals are inactive,

and the UART driving the transmitter inputs is inactive

for more than 30 seconds. They turn on again when

they sense a valid transition at any transmitter or receiv-

er input. AutoShutdown Plus saves power without

changes to the existing BIOS or operating system.

The MAX3225/MAX3227/MAX3245 also feature

MegaBaud™ operation, guaranteeing 1Mbps for high-

speed applications such as communicating with ISDN

modems. The MAX3224/MAX3226/MAX3244 guarantee

250kbps operation. The transceivers have a proprietary

low-dropout transmitter output stage enabling true RS-

232 performance from a +3.0V to +5.5V supply with a

dual charge pump. The charge pump requires only four

small 0.1µF capacitors for operation from a 3.3V supply.

The MAX3224–MAX3227 feature a logic-level output

(READY) that asserts when the charge pump is regulat-

ing and the device is ready to begin transmitting.

All devices are available in a space-saving TQFN,

TSSOP, and SSOP packages.

________________________Applications

Notebook, Subnotebook, and Palmtop Computers

Cellular Phones

Battery-Powered Equipment

Handheld Equipment

Peripherals

Printers

_Next Generation Device Features

♦♦

For Smaller Packaging:

MAX3228/MAX3229: +2.5V to +5.5V RS-232

Transceivers in UCSP™

♦♦

For Low-Voltage or Data Cable Applications:

MAX3380E/MAX3381E: +2.35V to +5.5V, 1µA,

2 Tx/2 Rx RS-232 Transceivers with ±15kV ESD-

Protected I/O and Logic Pins

♦♦

For Integrated ESD Protection:

MAX3222E/MAX3232E/MAX3237E/MAX3241E/

MAX3246E: ±15kV ESD-Protected, Down to 10nA,

+3.0V to +5.5V, Up to 1Mbps, True RS-232

Transceivers (MAX3246E Available in UCSP)

PART

MAX3224

MAX3225

MAX3226

1/1

2/2

NO. OF

DRIVERS/

RECEIVERS

READY

OUTPUT

✔

Auto-

Shut

down

Plus

✔

250k

GUARANTEED

DATA RATE

(bps)

MAX3227

MAX3244

MAX3245

3/5

1/1

✔

—

✔

250k

_____________________ Selector Guide

_______________Ordering Information

PART TEMP RANGE PIN-PACKAGE

MAX3224CPP+ 0°C to +70°C 20 PDIP

MAX3224CAP+ 0°C to +70°C 20 SSOP

MAX3224CTP+ 0°C to +70°C 20 TQFN-EP*

MAX3224CUP+ 0° C to +70°C 20 TSSOP

MAX3224EPP+ -40°C to +85°C 20 PDIP

MAX3224EAP+ -40°C to +85°C 20 SSOP

MAX3224ETP+ -40°C to +85°C 20 TQFN-EP*

MAX3224EUP+ -40° C to +85°C 20 TSSOP

Denotes a lead(Pb)-free/RoHS-compliant package.

EP = Exposed pad.

Ordering Information continued at end of data sheet.

19-1289; Rev 5; 2/11

MAX3224–MAX3227/

MAX3244/MAX3245

Summary of content (19 pages)

PAGE 1
MAX3224–MAX3227/ LE MAX3244/MAX3245 AVAILAB 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus ________________General Description The MAX3224–MAX3227/MAX3244/MAX3245 are 3Vpowered EIA/TIA-232 and V.28/V.24 communications interfaces with automatic shutdown/wakeup features and high data-rate capabilities. All devices achieve a 1µA supply current using Maxim’s revolutionary AutoShutdown Plus™ feature.
PAGE 2
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus ABSOLUTE MAXIMUM RATINGS VCC to GND ..............................................................-0.3V to +6V V+ to GND (Note 1) ..................................................-0.3V to +7V V- to GND (Note 1) ...................................................+0.3V to -7V V+ + ⏐V-⏐(Note 1) ................................................................
PAGE 3
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus ELECTRICAL CHARACTERISTICS (continued) (VCC = +3V to +5.5V, C1–C4 = 0.1µF, tested at 3.3V ±10%; C1 = 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%; TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS TRANSMITTER OUTPUTS Output Voltage Swing All transmitter outputs loaded with 3kΩ to ground ±5 ±5.
PAGE 4
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus TIMING CHARACTERISTICS—MAX3224/MAX3226/MAX3244 (VCC = +3V to +5.5V, C1–C4 = 0.1µF, tested at 3.3V ±10%; C1 = 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%; TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.
PAGE 5
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus __________________________________________Typical Operating Characteristics (VCC = +3.3V, 250kbps data rate, C1–C4 = 0.1µF, all transmitters loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.) -SLEW 10 +SLEW 8 6 4 VOUT3000 4000 5000 0 1000 2000 3000 4000 3000 4000 80 -SLEW 50 +SLEW 40 30 1 TRANSMITTER AT 1Mbps 1 TRANSMITTER AT 62.
PAGE 6
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus Typical Operating Characteristics (continued) (VCC = +3.3V, 250kbps data rate, C1–C4 = 0.1µF, all transmitters loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.) 1 TRANSMITTER AT 250kbps 2 TRANSMITTERS AT 15.
PAGE 7
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus Pin Description PIN MAX3224 MAX3225 MAX3226 MAX3227 MAX3244 MAX3245 NAME FUNCTION 19 1 — READY Ready to Transmit Output, Active High. READY is enabled high when V- goes below -4V and the device is ready to transmit. 2 1 2 28 C1+ 3 20 3 27 V+ +5.
PAGE 8
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus POWERMANAGEMENT UNIT OR KEYBOARD CONTROLLER VCC FORCEOFF FORCEON INVALID PROTECTION DIODE MAX3244 MAX3245 PREVIOUS RS-232 VCC I Rx 5kΩ UART Tx CPU GND I/O CHIP WITH UART 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 9
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus Table 1.
PAGE 10
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus +0.3V T_IN R_IN 30μs TIMER R -0.3V INVALID R_IN EDGE DETECT S 30sec TIMER EDGE DETECT INVALID ASSERTED IF ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR AT LEAST 30μs. Figure 3a. INVALID Functional Diagram, INVALID Low FORCEOFF AUTOSHDN R FORCEON Figure 3c. AutoShutdown Plus Logic +2.7V FORCEOFF POWERDOWN* FORCEON R_IN 30μs TIMER R -2.
PAGE 11
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus RECEIVER INPUTS INVALID } REGION TRANSMITTER INPUTS TRANSMITTER OUTPUTS INVALID OUTPUT VCC tINVL 0 tINVH tAUTOSHDN tAUTOSHDN tWU tWU *VCC OUTPUT 0 V+ VCC 0 V- *MAX3224–MAX3227 Figure 4b.
PAGE 12
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus Software-Controlled Shutdown If direct software control is desired, use INVALID to indicate DTR or Ring Indicator signal. Tie FORCEOFF and FORCEON together to bypass the AutoShutdown Plus so the line acts like a SHDN input. transmitter is loaded with 3kΩ in parallel with 1000pF. The transmitter outputs display no ringing or undesirable transients as they come out of shutdown.
PAGE 13
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus High Data Rates The MAX3224/MAX3226/MAX3244 maintain the RS-232 ±5.0V minimum transmitter output voltage even at high data rates. Figure 7 shows a transmitter loopback test circuit. Figure 8 shows a loopback test result at 120kbps, and Figure 9 shows the same test at 250kbps. For Figure 8, all transmitters were driven simultaneously at 120kbps into RS-232 loads in parallel with 1000pF.
PAGE 14
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus +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+ MAX3244 MAX3245 COMPUTER SERIAL PORT 3 V- C4 0.
PAGE 15
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus drove all serial mice tested and met their respective current and voltage requirements. The MAX3244/ MAX3245 dual charge pump ensures the transmitters will supply at least ±5V during worst-case conditions. Figure 11a shows the transmitter output voltages under increasing load current. Figure 11b shows a typical mouse connection.
PAGE 16
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus ___________________________________________________Typical Operating Circuits +3.3V +3.3V 15 0.1μF CBYPASS 2 C1+ C1 0.1μF 4 C15 C2 0.1μF 6 C2+ 3 V+ MAX3226 MAX3227 V- 9 R1OUT C3 0.1μF C1 0.1μF C4 0.1μF C2 0.1μF 7 C2- 11 T1IN 12 24 1 2 VCC C3 0.1μF C1C2+ MAX3244 MAX3245 C1 0.
PAGE 17
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.
PAGE 18
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.
PAGE 19
MAX3224–MAX3227/MAX3244/MAX3245 1µA Supply Current, 1Mbps, 3.0V to 5.5V, RS-232 Transceivers with AutoShutdown Plus Revision History REVISION NUMBER REVISION DATE 3 5/05 Added new packaging types 4 10/08 Added automotive qualified product information 1, 18 5 2/11 Changed all the parts in the Ordering Information to lead-free 1, 18 DESCRIPTION PAGES CHANGED Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product.