MAX3243ECAI ,15kV ESD-Protected / 1A / 3.0V to 5.5V / 250kbps / RS-232 Transceivers with AutoShutdownFeaturesThe MAX3221E/MAX3223E/MAX3243E are 3V-powered' ESD Protection for RS-232 I/O Pins:EIA/TIA-2 ..
MAX3243ECAI+ ,±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps, RS-232 Transceivers with AutoShutdownfeatures, high data- to +5.5V RS-232 Transceivers in UCSP™rate capabilities, and enhanced electrost ..
MAX3243ECAI+T ,±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps, RS-232 Transceivers with AutoShutdownGeneral Description Next Generation Device
MAX3243ECAI-T ,±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps, RS-232 Transceivers with AutoShutdownApplications:1µA supply current with Maxim’s revolutionaryMAX3380E/MAX3381E: +2.35V to +5.5V, 1µA,A ..
MAX3243ECDB ,3-V to 5.5-V Multichannel RS-232 Line Driver/Receiver With +/-15kV IEC ESD Protection 28-SSOP 0 to 70FEATURESDB, DW, OR PW PACKAGE2• Single-Chip and Single-Supply Interface for(TOP VIEW)IBM™ PC/AT™ Se ..
MAX3243ECDB ,3-V to 5.5-V Multichannel RS-232 Line Driver/Receiver With +/-15kV IEC ESD Protection 28-SSOP 0 to 70FEATURESDB, DW, OR PW PACKAGE2• Single-Chip and Single-Supply Interface for(TOP VIEW)IBM™ PC/AT™ Se ..
MAX685EEE ,Dual-Output Positive and Negative / DC-DC Converter for CCD and LCDELECTRICAL CHARACTERISTICS (continued)(V = VP = 5V, T = 0°C to +85°C unless otherwise noted. Typica ..
MAX685EEE ,Dual-Output Positive and Negative / DC-DC Converter for CCD and LCDFeaturesThe MAX685 DC-DC converter provides low-noise dual' Dual Output Using a Single Inductoroutp ..
MAX685EEE ,Dual-Output Positive and Negative / DC-DC Converter for CCD and LCDMAX68519-1353; Rev 0; 4/98Dual-Output (Positive and Negative), DC-DC Converter for CCD and LCD
MAX685EEE ,Dual-Output Positive and Negative / DC-DC Converter for CCD and LCDELECTRICAL CHARACTERISTICS(V = VP = 5V, T = 0°C to +85°C unless otherwise noted. Typical values are ..
MAX685EEE ,Dual-Output Positive and Negative / DC-DC Converter for CCD and LCDApplicationsCamcorders LCDsDigital Cameras CCD Imaging DevicesINPUTNotebooks POSITIVE2.7V TO 5.5VOU ..
MAX685EEE+ ,Dual-Output (Positive and Negative), DC-DC Converter for CCD and LCDFeaturesThe MAX685 DC-DC converter provides low-noise dual♦ Dual Output Using a Single Inductoroutp ..
MAX3221ECAE-MAX3221EEAE-MAX3243ECAI-MAX3243ECWI-MAX3243EEAI
15kV ESD-Protected / 1A / 3.0V to 5.5V / 250kbps / RS-232 Transceivers with AutoShutdown
General DescriptionThe MAX3221E/MAX3223E/MAX3243E are 3V-powered
EIA/TIA-232 and V.28/V.24 communications interfaces
with automatic shutdown/wakeup features, high data-
rate capabilities, and enhanced electrostatic discharge
(ESD) protection. All transmitter outputs and receiver
inputs are protected to ±15kV using IEC 1000-4-2 Air-
Gap Discharge, to ±8kV using IEC 1000-4-2 Contact
Discharge, and to ±15kV using the Human Body Model.
The MAX3221E/MAX3223E/MAX3243E achieve a
1µA supply current with Maxim’s revolutionary
AutoShutdown™ feature. They save power without
changes to the existing BIOS or operating system by enter-
ing low-power shutdown mode when the RS-232 cable is
disconnected, or when the transmitters of the connected
peripherals are off.
The transceivers have a proprietary low-dropout trans-
mitter output stage, delivering 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 capaci-
tors for operation from a +3.3V supply. Each device is
guaranteed to run at data rates of 250kbps while main-
taining RS-232 output levels.
The MAX3221E contains just one driver and one receiver,
making it the smallest single-supply RS-232 transceiver.
The MAX3223E has two drivers and two receivers. The
MAX3243E is a complete 3-driver/5-receiver serial port
ideal for notebook or subnotebook computers. It also
includes two noninverting receiver outputs that are always
active, allowing external devices to be monitored without
forward biasing the protection diodes in circuitry that may
be powered down.
The MAX3221E, MAX3223E, and MAX3243E are avail-
able in space-saving SSOP packages.
ApplicationsNotebook, Subnotebook, and Palmtop Computers
Cellular Phones
Battery-Powered Equipment
Hand-Held Equipment
Peripherals
Printers
FeaturesESD Protection for RS-232 I/O Pins:
±15kV—Human Body Model
±8kV—IEC1000-4-2, Contact Discharge
±15kV—IEC1000-4-2, Air-Gap DischargeLatchup Free1µA Supply Current 250kbps Guaranteed Data Rate6V/µs Guaranteed Slew RateMeets EIA/TIA-232 Specifications Down to 3.0VSmallest Single-Supply RS-232 Transceiver
(MAX3221E)Guaranteed Mouse Driveability (MAX3243E)Small 0.1µF Capacitors
MAX3221E/MAX3223E/MAX3243E
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown19-1283; Rev 2; 1/98
AutoShutdown is a trademark of Maxim Integrated Products.
†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; 5,649,210; and other patents pending.
Pin Configurations appear at end of data sheet.
Typical Operating Circuits appear at end of data sheet.
Selector Guide
MAX3221E/MAX3223E/MAX3243
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(VCC= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
VCCto 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).................................................................+13V
Input Voltages
T_IN, EN, FORCEON, FORCEOFFto GND............-0.3V to +6V
R_IN to GND......................................................................±25V
Output Voltages
T_OUT to GND................................................................±13.2V
R_OUT, R2OUTB, INVALIDto GND.........-0.3V to (VCC+ 0.3V)
Short-Circuit Duration
T_OUT to GND.........................................................Continuous
Continuous Power Dissipation (TA= +70°C)
16-Pin SSOP (derate 7.14mW/°C above +70°C)...........571mW
20-Pin Plastic DIP (derate 11.11mW/°C above +70°C)....889mW
20-Pin SSOP (derate 8.00mW/°C above +70°C)...........640mW
28-Pin Wide SO(derate 12.50mW/°C above +70°C)............1W
28-Pin SSOP(derate 9.52mW/°C above +70°C)............762mW
Operating Temperature Ranges
MAX32_ _EC_ _....................................................0°C to +70°C
MAX32_ _EE_ _..................................................-40°C to +85°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10sec).............................+300°C
Note 1:V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
MAX3221E/MAX3223E/MAX3243
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
ELECTRICAL CHARACTERISTICS (continued)(VCC= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
Typical Operating Characteristics(VCC= +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩand CL, TA = +25°C, unless otherwise noted.)
MAX3221E/MAX3223E/MAX3243
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
TIMING CHARACTERISTICS—MAX3221E/MAX3223E/MAX3243E(VCC= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
Note 2:C1–C4 = 0.1µF, tested at 3.3V ±10%. C1 = 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%.
Note 3:Transmitter skew is measured at the transmitter zero cross points.
MAX3221E/MAX3223E/MAX3243
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
Typical Operating Characteristics (continued)(VCC= +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩand CL, TA= +25°C, unless otherwise noted.)
MAX3221E/MAX3223E/MAX3243
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
Pin Description
_______________Detailed Description
Dual Charge-Pump Voltage ConverterThe MAX3221E/MAX3223E/MAX3243E’s internal power
supply consists of a regulated dual charge pump that
provides output voltages of +5.5V (doubling charge
pump) and -5.5V (inverting charge pump), over the
+3.0V to +5.5V VCCrange. The charge pumps operate
in discontinuous mode: if the output voltages are less
than 5.5V, the charge pumps are enabled; if the output
voltages exceed 5.5V, the charge pumps are disabled.
Each charge pump requires a flying capacitor (C1, C2)
and a reservoir capacitor (C3, C4) to generate the V+
and V- supplies.
RS-232 TransmittersThe transmitters are inverting level translators that con-
vert CMOS-logic levels to 5.0V EIA/TIA-232 levels. They
guarantee a 250kbps data rate with worst-case loads
of 3kΩin parallel with 1000pF, providing compatibility
with PC-to-PC communication software such as
LapLink™. Transmitters can be paralleled to drive mul-
tiple receivers. The MAX3243E has been specifically
designed to drive serial mice. Figure 1shows a com-
plete system connection.
When FORCEOFFis driven to ground, or the
AutoShutdown circuitry senses invalid voltage levels on
all receiver inputs, the transmitters are disabled and the
outputs are forced into a high-impedance state. When
powered off or shut down, the output can be driven up
to ±12V. The transmitter inputs do not have pull-up
resistors.
MAX3221E/MAX3223E/MAX3243
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
RS-232 ReceiversThe MAX3221E/MAX3223E/MAX3243E’s receivers con-
vert RS-232 signals to CMOS-logic output levels. All
receivers have inverting three-state outputs and can be
active or inactive. In shutdown (FORCEOFF= low) or in
AutoShutdown, the MAX3221E/MAX3223E’s receivers
are active (Table 1). Drive ENhigh to place the receiv-
er(s) in a high-impedance state. The MAX3243E’s
receivers are high-impedance when the part is in shut-
down (FORCEOFF= low).
The MAX3243E features an extra, always-active com-
plementary output (R2OUTB). R2OUTB monitors
receiver activity while the other receivers are high-
impedance. This allows Ring Indicator to be monitored
without forward biasing other devices connected to the
receiver outputs. This is ideal for systems where VCC
drops to 0 in shutdown to accommodate peripherals
such as UARTs (Figure 2).Figure 1. Interface Under Control of PMU
Figure 2. The MAX3243E detects RS-232 activity when the
UART and interface are shut down.
MAX3221E/MAX3223E/MAX3243
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
Table 1. Output Control Truth TableFigure 3a. MAX32_ _E Entering 1µA Supply Mode via
AutoShutdown
Figure 3b. MAX32__E with Transmitters Enabled Using
AutoShutdown
X = Don’t Care
The MAX3221E/MAX3223E/MAX3243E feature an
INVALIDoutput that is enabled low when no valid RS-232
signal levels have been detected on all receiver inputs.
INVALIDis functional in any mode (Figures 3 and 5).
AutoShutdownThe MAX3221E/MAX3223E/MAX3243E achieve a 1µA
supply current with Maxim’s new AutoShutdown fea-
ture, which operates when FORCEON is low and
FORCEOFFis high. When these devices sense no valid
signal levels on all receiver inputs for 30µs, the on-
board charge pump and drivers are shut off, reducing
supply current to 1µA. This occurs if the RS-232 cable
is disconnected or the connected peripheral transmit-
ters are turned off. The device 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.
