MAX221ECUE ,【15kV ESD-Protected, +5V, 1レA, Single RS-232 Transceiver with AutoShutdownELECTRICAL CHARACTERISTICS(V = +5V ±10%, C1–C4 = 0.1µF, T = T to T , unless otherwise noted. Typica ..
MAX221ECUE+ ,±15kV ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdownFeaturesThe MAX221E is a +5V powered, single transmit/♦ Single RS-232 Transceiver in a Small 16-Pin ..
MAX221EEAE+ ,±15kV ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdownELECTRICAL CHARACTERISTICS(V = +5V ±10%, C1–C4 = 0.1µF, T = T to T , unless otherwise noted. Typica ..
MAX221EEAE+ ,±15kV ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdownFeaturesThe MAX221E is a +5V powered, single transmit/♦ Single RS-232 Transceiver in a Small 16-Pin ..
MAX221EEAE+ ,±15kV ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdownApplicationsTypical Operating CircuitMaintenance/Diagnostic PortsIndustrial Systems+5V 15Telecommun ..
MAX221EEAE-T ,±15kV ESD-Protected, +5V, 1µA, Single RS-232 Transceiver with AutoShutdownfeatures enhanced electrostatic discharge±15kV—IEC 1000-4-2, Air-Gap Discharge(ESD) protection. Bot ..
MAX530ACAG ,+5V, Low-Power, Parallel-Input, Voltage-Output, 12-Bit DACfeatures but with a serial data interface, referto the MAX531/MAX538/MAX539 data sheet.ERRORPART TE ..
MAX530ACNG ,+5V, Low-Power, Parallel-Input, Voltage-Output, 12-Bit DACMAX53019-0168; Rev 3; 7/95+5V, Low-Power, Parallel-Input, Voltage-Output, 12-Bit DAC_______________
MAX530AEAG ,+5V, Low-Power, Parallel-Input, Voltage-Output, 12-Bit DACapplications. In40µA Shutdown-Mode Currentaddition, the SSOP (Shrink-Small-Outline-Package) mea-sur ..
MAX530AEAG+ ,+5V, Low-Power, Parallel-Input, Voltage-Output, 12-Bit DACapplications. In40μA Shutdown-Mode Currentaddition, the SSOP (Shrink-Small-Outline-Package) mea-sur ..
MAX530AENG+ ,+5V, Low-Power, Parallel-Input, Voltage-Output, 12-Bit DACFeatures♦ Buffered Voltage OutputThe MAX530 is a low-power, 12-bit, voltage-output digi-tal-to-anal ..
MAX530AEWG ,+5V, Low-Power, Parallel-Input, Voltage-Output, 12-Bit DACApplications /MAX530ACNG 0°C to +70°C 24 Narrow Plastic DIP ±2Battery-Powered Data-Conversion Produ ..
MAX221ECUE-MAX221EEUE
【15kV ESD-Protected, +5V, 1レA, Single RS-232 Transceiver with AutoShutdown
General DescriptionThe MAX221E is a +5V powered, single transmit/
receive RS-232 and V.28 communications interface with
automatic shutdown/wake-up features and high data
rate capabilities.
The MAX221E features enhanced electrostatic discharge
(ESD) protection. Both the transmitter output and receiver
input are protected to ±15kV using the IEC 1000-4-2 Air-
Gap Discharge Method, to ±8kV using the IEC 1000-4-2
Contact Discharge Method, and to ±15kV using the
Human Body Model.
The MAX221E achieves a low 1µA supply current with
Maxim’s revolutionary AutoShutdown™ feature.
AutoShutdown saves power without changes to the
existing BIOS or operating system by entering low-
power shutdown mode when the RS-232 cable is dis-
connected or when the transmitter of the connected
peripheral is off. The MAX221E wakes up and drives the
INVALIDpin high when an active RS-232 cable is con-
nected, signaling the host that a peripheral is connected
to the communications port.
The MAX221E is available in a 16-pin SSOP package as
well as a 16-pin TSSOP that uses 50% less board space
than a 16-pin SO.
ApplicationsMaintenance/Diagnostic Ports
Industrial Systems
Telecommunications
Set-Top Boxes
FeaturesSingle RS-232 Transceiver in a Small 16-Pin TSSOPESD Protection for RS-232 I/O Pins
±15kV—Human Body Model
±8kV—IEC 1000-4-2, Contact Discharge
±15kV—IEC 1000-4-2, Air-Gap DischargeLatchup Free1µA Supply CurrentAutoShutdown Saves Power without Changes
to BIOSGuaranteed 250kbps Data Rate
MAX221E
±15kV ESD-Protected, +5V, 1µA, Single RS-232
Transceiver with AutoShutdown ypical Operating Circuit19-1527; Rev 0; 8/99
Pin Configuration
Ordering InformationAutoShutdown is a trademark of Maxim Integrated Products.
MAX221E
±15kV ESD-Protected, +5V, 1µA, Single RS-232
Transceiver with AutoShutdown
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(VCC = +5V ±10%, C1–C4 = 0.1µF, 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.
VCC..........................................................................-0.3V to +6V
V+ ...............................................................(VCC- 0.3V) to +14V
V- ...........................................................................-14V to +0.3V
Input Voltages
TIN............................................................-0.3V to (V+ + 0.3V)
RIN...................................................................................±30V
FORCEON, FORCEOFF, EN..................-0.3V to (VCC+ 0.3V)
Output Voltages
TOUT................................................(V- - 0.3V) to (V+ + 0.3V)
ROUT, INVALID......................................-0.3V to (VCC+ 0.3V)
Short-Circuit Duration, TOUT.....................................Continuous
Continuous Power Dissipation (TA= +70°C)
16-Pin TSSOP (derated 6.7mW/°C above +70°C).......533mW
16-Pin SSOP (derated 7.1mW/°C above +70°C).........571mW
Operating Temperature Range
MAX221EC_ _.....................................................0°C to +70°C
MAX221EE_ _..................................................-40°C to +85°C
Maximum Junction Temperature....................................+150°C
Storage Temperature Range ...........................-65°C to +150°C
Lead Temperature (soldering, 10sec)............................+300°C
MAX221E
±15kV ESD-Protected, +5V, 1µA, Single RS-232
Transceiver with AutoShutdown
TIMING CHARACTERISTICS(VCC= +5V ±10%, C1–C4 = 0.1µF, TA = TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
ELECTRICAL CHARACTERISTICS (continued)(VCC = +5V ±10%, C1–C4 = 0.1µF, TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
Note 1:Transmitter skew is measured at the transmitter zero crosspoints.
MAX221E
±15kV ESD-Protected, +5V, 1µA, Single RS-232
Transceiver with AutoShutdown10002000300040005000
SLEW RATE vs.
LOAD CAPACITANCEMAX221Etoc02
LOAD CAPACITANCE (pF)
SLEW RATE (V/
Pin Description
Typical Operating Characteristics(VCC= +5V, 250kbps data rate, 0.1µF capacitors, transmitter loaded with 3kWand CL, TA= +25°C, unless otherwise noted.)
MAX221E
±15kV ESD-Protected, +5V, 1µA, Single RS-232
Transceiver with AutoShutdown
_______________Detailed Description
Dual Charge-Pump Voltage ConverterThe MAX221E’s internal power supply consists of a
dual charge pump that provides a positive output volt-
age (doubling charge pump) and negative output volt-
age (inverting charge pump) from a single +5V supply.
The charge pumps operate in continuous mode. Each
charge pump requires a flying capacitor (C1, C2) and a
reservoir capacitor (C3, C4) to generate the V+ and V-
supplies.
RS-232 TransmitterThe transmitter is an inverting level translator that con-
verts CMOS-logic levels to 5.0V EIA/TIA-232 levels. It
guarantees a 250kbps data rate with worst-case loads
of 3kWin parallel with 1000pF.
When FORCEOFFis driven to ground, or when the
AutoShutdown circuitry senses invalid voltage levels on
the receiver input, the transmitter is disabled and the
output is forced into a high-impedance state. The trans-
mitter input does not have a pull-up resistor.
RS-232 ReceiverThe MAX221E’s receiver converts RS-232 signals to
CMOS-logic output levels. The receiver has an inverting
three-state output and can be active or inactive. In
shutdown (FORCEOFF= low) or in AutoShutdown, the
receiver is active (Table 1). Drive ENhigh to place the
receiver in a high-impedance state. The receiver is
high-impedance when the MAX221E is in shutdown
(FORCEOFF= low).
The MAX221E’s INVALIDoutput is pulled low when
there is no valid RS-232 signal level detected on the
receiver input. INVALIDis functional in any mode
(Figures 2 and 3).
AutoShutdownThe MAX221E achieves 1µA supply current with
Maxim’s AutoShutdown feature, which operates when
FORCEON is low and FORCEOFFis high. When the
device senses no valid signal levels on the receiver
input for 30µs, the on-board charge pump and driver
are shut off, reducing supply current to 1µA. This
occurs if the RS-232 cable is disconnected or the con-
nected peripheral transmitter is turned off. The
MAX221E turns on again when a valid level is applied
to the RS-232 receiver input. As a result, the system
saves power without changes to the existing BIOS or
operating system.
Table 1 and Figure 2c summarize the MAX221E operat-
ing modes. FORCEON and FORCEOFFoverride
AutoShutdown. When neither control is asserted, the
device selects between these states automatically,
based on the receiver input level. Figures 2a, 2b, and
3a depict valid and invalid RS-232 receiver levels.
Figure 3 shows the input levels and timing diagram for
AutoShutdown operation.
A device or another system with AutoShutdown con-
nected to the MAX221E may need time to wake up.
Figure 4 shows a circuit that forces the transmitter on
for 100ms, allowing enough time for the other system to
realize that the MAX221E is awake. If the other system
transmits valid RS-232 signals within that time, the
RS-232 ports on both systems remain enabled.
When shut down, the device’s charge pumps turn off,
V+ is pulled to VCC, V- is pulled to ground, and the
transmitter output is high impedance. The time required
to exit shutdown is typically 100µs (Figure 3b).
MAX221E
±15kV ESD-Protected, +5V, 1µA, Single RS-232
Transceiver with AutoShutdown
Table 1. Output Control Truth Table
Table 2. INVALIDTruth Tablex = Don’t care
