MAX212CAG-MAX212EAG Fast Delivery |IC PHOENIX CO.,LIMITED

MAX212CAG ,+3V-powered, low-power, true RS-232 tranceiver.MAX21219-0162; Rev 2; 2/94+3V-Powered, Low-Power,True RS-232 Transceiver________________
MAX212CAG ,+3V-powered, low-power, true RS-232 tranceiver.Applications1Computers 23 214V+ LN LP V-Notebooks/Palmtops/Subnotebooks+3.3V 3VCCPrintersDC-DC CONV ..
MAX212CAG ,+3V-powered, low-power, true RS-232 tranceiver.FeaturesSUPERIOR TO BIPOLAR:The MAX212 RS-232 transceiver is intended for 3V-pow-ered EIA/TIA-232E ..
MAX212CAG+ ,+3V-Powered, Low-Power, True RS-232 TransceiverFeaturesSUPERIOR TO BIPOLAR:The MAX212 RS-232 transceiver is intended for 3V-pow-ered EIA/TIA-232E ..
MAX212EAG ,+3V-powered, low-power, true RS-232 tranceiver.General Description ________
MAX2135AETN/V+T ,ISDB-T/DVB-T Diversity Tunerth8 EditionAUTOMOTIVESolutions Guidewww.maximintegrated.com/automotiveDownloaded from: http://www.i ..
MAX522ESA ,Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO PackageFeaturesThe MAX522 contains two 8-bit, buffered, voltage-output' Operates from a Single +2.7V to +5 ..
MAX522ESA ,Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO PackageFeaturesThe MAX522 contains two 8-bit, buffered, voltage-output' Operates from a Single +2.7V to +5 ..
MAX522ESA+ ,Dual, 8-Bit, Voltage-Output Serial DAC in 8-Pin SO PackageFeaturesThe MAX522 contains two 8-bit, buffered, voltage-output' Operates from a Single +2.7V to +5 ..
MAX5230AEEE ,3V/5V, 12-Bit, Serial Voltage-Output Dual DACs with Internal ReferenceApplications Space-Saving 16-Pin QSOP PackageIndustrial Process ControlsAutomatic Test EquipmentOr ..
MAX5230AEEE+ ,3V/5V, 12-Bit, Serial Voltage-Output Dual DACs with Internal ReferenceApplicationsIndustrial Process ControlsAutomatic Test EquipmentOrdering InformationDigital Offset a ..
MAX5230AEEE+ ,3V/5V, 12-Bit, Serial Voltage-Output Dual DACs with Internal ReferenceELECTRICAL CHARACTERISTICS—MAX5231(V = +4.5V to +5.5V, OS_ = AGND = DGND = 0, R = 5kΩ, C = 100pF, T ..

MAX212CAG-MAX212EAG
+3V-powered, low-power, true RS-232 tranceiver.
________________General Description
The MAX212 RS-232 transceiver is intended for 3V-pow-
ered EIA/TIA-232E and V.28/V.24 communication inter-
faces where 3 drivers and 5 receivers are needed with
minimum power consumption. The operating voltage
range extends from 3.6V down to 3.0V while still main-
taining true RS-232 and EIA/TIA-562 voltage levels.
A 1µA typical shutdown mode reduces power con-
sumption, extending battery life in portable systems.
While shut down, all receivers can remain active or can
be disabled under logic control. This enables a system
incorporating the CMOS MAX212 to be in low-power
shutdown mode and monitor incoming RS-232 activity.
A guaranteed data rate of 120kbps provides compati-
bility with popular software for communicating with per-
sonal computers.
Three-state drivers on all receiver outputs are provided
so that multiple receivers, generally of different inter-
face standards, can be wire-ORed at the UART.
The MAX212 is available in both small-outline (SO) and
shrink-small-outline (SSOP) packages. The SSOP
package occupies less than half of the board area
required by the equivalent SO package.
________________________Applications
Computers
Notebooks/Palmtops/Subnotebooks
Printers
Peripherals
Instruments
____________________________Features
SUPERIOR TO BIPOLAR:Operates from Single +3.0V to +3.6V Supply24-Pin SSOP or Wide SO PackagesMeets All EIA/TIA-232E & EIA/TIA-562
Specifications3mA Max Supply Current (Unloaded)1µA Low-Power Shutdown ModeAll Receivers Active During Low-Power ShutdownMouse Compatible at 3.0VLow-Cost, Surface-Mount External Components120kbps Guaranteed Data Rate—LapLink™
CompatibleThree-State Receiver OutputsEvaluation Kit AvailableFlow-Through Pinout
MAX212
+3V-Powered, Low-Power,
True RS-232 Transceiver
________________________________________________________________Maxim Integrated Products1
Call toll free 1-800-998-8800 for free samples or literature.
19-0162; Rev 2; 2/94
™LapLink is a registered trademark of Traveling Software.
_______________Ordering Information
* Dice are tested at TA= +25°C only.
___________Typical Operating Circuit
MAX212
+3V-Powered, Low-Power,rue RS-232 Transceiver_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC= 3.0V to 3.6V, TA= TMINto TMAX, unless otherwise noted.)
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.
Supply Voltages
VCC.....................................................................-0.3V to +4.6V
V+............................................................(VCC- 0.3V) to +7.4V
V-........................................................................-7.4V to +2.0V
LN..............................................................-0.3V to (V+ + 1.0V)
LP.......................................................(V- - 1.0V) to (V+ + 0.3V)
Input Voltages
T_IN, –S—D, EN..............................................-0.3V to (V+ + 0.3V)
R_IN...................................................................................±25V
Output Voltages
T_OUT................................................................................±15V
R_OUT........................................................-0.3V to (V+ + 0.3V)
Short-Circuit Duration, T_OUT.....................................Continuous
Continuous Power Dissipation (TA= +70°C)
Wide SO (derate 11.76mW/°C above +70°C)...............941mW
SSOP (derate 8.00mW/°C above +70°C).....................640mW
Lead Temperature (soldering, 10sec).............................+300°C
MAX212
+3V-Powered, Low-Power,
True RS-232 Transceiver
_______________________________________________________________________________________3
TIMING CHARACTERISTICS
(VCC= 3.0V to 3.6V, TA= TMINto TMAX, unless otherwise noted.)
__________________________________________Typical Operating Characteristics
(VCC= 3.3V, TA = +25°C, unless otherwise noted.)
DATA RATE (kbps)
SUPPLY POWER (mW)
SUPPLY POWER vs.
DATA RATE
212 GR4
DATA RATE (kbps)
OUTPUT VOLTAGE (V)
TRANSMITTER OUTPUT VOLTAGE vs.
DATA RATE
212 GR5
200250
MAX212
+3V-Powered, Low-Power,rue RS-232 Transceiver_______________________________________________________________________________________
____________________________Typical Operating Characteristics (continued)
(VCC= 3.3V, TA = +25°C, unless otherwise noted.)
LOAD CAPACITANCE (pF)
SLEW RATE (V/
SLEW RATE vs.
LOAD CAPACITANCE
212 GR6
4500
_____________________Pin Description
_______________Detailed Description
The MAX212 line driver/receiver is intended for 3V-
powered EIA/TIA-232E and V.28/V.24 communications
interfaces where 3 drivers and 5 receivers are
required. The operating voltage range extends from
3.6V down to 3.0V while still maintaining true RS-232
and EIA/TIA-562 transmitter output voltage levels.
The circuit comprises three sections: power supply,
transmitters, and receivers. The power-supply sec-
tion converts the supplied 3V to about ±6.5V, to pro-
vide the voltages necessary for the drivers to meet
true RS-232 levels. External components are small
and inexpensive.
The transmitters and receivers are guaranteed to oper-
ate at data rates of 120kbps.
A shutdown mode reduces current to 1µA to extend
battery life in portable systems. While shut down, all
receivers can remain active or can be disabled under
logic control. This enables a system incorporating the
MAX212 to be in low-power shutdown mode and still
monitor incoming RS-232 activity.
Three-state drivers on all receiver outputs are provided
so that multiple receivers, generally of different inter-
face standards, can be wire-ORed at the UART.
SUPPLY VOLTAGE (V)
SUPPLY POWER (mW)
SUPPLY POWER vs.
SUPPLY VOLTAGE
212 GR2100020003000
LOAD CAPACITANCE (pF)
SUPPLY CURRENT (mA)
SUPPLY CURRENT vs.
LOAD CAPACITANCE
212 GR3
4000
MAX212
+3V-Powered, Low-Power,
True RS-232 Transceiver
_______________________________________________________________________________________5
Switch-Mode Power Supply
The switch-mode power supply uses a single inductor
with two inexpensive diodes and two capacitors to
generate ±6.5V from the 3.0V to 3.6V input. Figure 1
shows the complete circuit for the power supply.
Use a 15mH inductor with a saturation current rating of at
least 350mA and under 1Wresistance. Sample surface-
mount inductors are available from Maxim. Use 1N6050
diodes or equivalent. Surface-mount equivalents for the
1N6050 include the Motorola MMBD6050LT1, Philips
PMBD6050, and Allegro (formerly Sprague) TMPD6050LT.
For C1 and C2, use ceramic capacitors with values no
less than indicated in Figure 1. These capacitors deter-
mine the ripple on V+ and V-, but not the absolute volt-
ages. Bypass VCCto GND with at least 0.33mF close to
the MAX212. Increase this to 4.7mF if there are no other
VCCsupply bypass components less than 6 inches
(15cm) away from the MAX212.
Component suppliers are listed in Table 1.
RS-232 Drivers
All three drivers are identical and deliver EIA/TIA-232E
and EIA/TIA-562 output voltage levels when VCCis
between 3.0V and 3.6V. Disable the drivers by taking
the –S—Dpin to GND. The transmitter outputs are forced
into a high-impedance state when –S—Dis grounded.
RS-232 Receivers
All five receivers are identical and accept
EIA/TIA-232E and EIA/TIA-562 input signals. The CMOS
receiver outputs swing rail-to-rail (0V to VCC). When EN
is high, the receivers are active regardless of –S—D’sstatus.
When EN is low, the receivers’ outputs are put into a
high-impedance state. This allows two RS-232 ports (or
two parts of different types) to be wire-ORed at the UART.
Figure 1. Typical Application Circuit
Table 1. Suggested Component Suppliers
MAX212
+3V-Powered, Low-Power,rue RS-232 Transceiver_______________________________________________________________________________________
Operating Modes–S—Dand EN determine the operation of the MAX212 follows:
Shutdown
V+ and V- are disabled and the transmitters are put into
a high-impedance state when –S—Dis taken to logic low.
Receiver operation is not affected, but power consump-
tion is dramatically reduced while in shutdown mode.
Supply current is minimized when the receiver inputs are
static in any of three states: floating (ground), less than
GND, or greater than VCC. This will be true for all static
RS-232 conditions. The presence of AC signals on receiv-
er inputs will increase VCCcurrent in shutdown.
From a low-power system perspective, powering-up with
non-critical or unused sections of circuitry shut down or
deselected is generally recommended. Activating these
sections only when required saves power and reduces
power-up current surges. Powering-up the MAX212 in
shutdown mode (holding the shutdown pin, –S—D, low until VCC> 2.7V), helps to achieve this.
Driving the MAX212 from 5V Logic
The MAX212 can interface with 5V logic while it operates
from a 3V supply, however a 200kΩseries resistor between–S—Dand the +5V logic signal is required (see Figure 2).
This protects the MAX212 by preventing –S—Dfrom sinking
current while V+ is powering up. Also, the UART must not
be permitted to send a logic high to the MAX212’s EN or
transmitter input pins until –S—Dis high (not shut down).
Mouse Driveability
The MAX212 has been specifically designed to power
serial mice while operating from low-voltage power
supplies. It has been tested with samples of ten major
mouse models from six manufacturers, including the
leading three, Logitech (5 models), Mouse Systems,
and Microsoft. The MAX212 successfully drove all seri-
al mice and met their respective current and voltage
requirements (Figure 1).
Figure 3 shows the transmitter output voltages under
increasing load current. The MAX212’s switching regu-
lator ensures the transmitters will supply at least ±5V
during worst-case load conditions.
EIA/TIA-232E and 562 Standards
Most of the power drawn by RS-232 circuits is con-
sumed because the EIA/TIA-232E standard demands
that at least ±5V be delivered by the transmitters to
impedances that can be as low as 3kΩ. For applica-
____________________________+3V Powered RS-232 Transceivers from Maxim

Partno	Mfg	Dc	Qty	Available	Descript
MAX212CAG	MAXIM	N/a	236	avai	+3V-powered, low-power, true RS-232 tranceiver.
MAX212CAG		N/a	51	avai	+3V-powered, low-power, true RS-232 tranceiver.
MAX212CAG	MAX	N/a	26	avai	+3V-powered, low-power, true RS-232 tranceiver.
MAX212EAG	MAXIM	N/a	23	avai	+3V-powered, low-power, true RS-232 tranceiver.