MAX32_ _C_ _.......................................................0°C to +70°C
MAX32_ _E_ _ ....................................................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1:
V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
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.
Electrical Characteristics
(V
CC
= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
DC CHARACTERISTICS
Supply Current, AutoShutdown
Supply Current, Shutdown
Supply Current,
AutoShutdown Disabled
Input Logic Threshold Low
Input Logic Threshold High
Input Leakage Current
Output Leakage Current
Output Voltage Low
Output Voltage High
All R_IN open, FORCEON = GND,
V
CC
= 3.3V
FORCEOFF
= V
CC
or 5.0V,
FORCEOFF
= GND
T
A
= +25°C FORCEON =
FORCEOFF
= V ,
CC
CONDITIONS
MIN
TYP
MAX
UNITS
1.0
1.0
0.3
10
10
1.0
µA
µA
mA
no load
T_IN, FORCEON,
FORCEOFF, EN
(MAX3223)
T_IN, EN, FORCEON,
FORCEOFF
T_IN, EN, FORCEON,
FORCEOFF
Receivers disabled
I
OUT
= 1.6mA
I
OUT
= -1.0mA
Positive threshold
Negative threshold
-2.7
-0.3
V
CC
- 0.6
V
CC
= 3.3V
V
CC
= 5.0V
2.0
2.4
LOGIC INPUTS AND RECEIVER OUTPUTS
0.8
V
V
±0.01
±0.05
±1.0
±10
0.4
V
CC
- 0.1
2.7
µA
µA
V
V
AUTOSHUTDOWN
(FORCEON = GND,
FORCEOFF
= V
CC
)
Receiver Input Thresholds to
Transmitters Enabled
Receiver Input Thresholds to
Transmitters Disabled
INVALID
Output Voltage Low
INVALID
Output Voltage High
Receiver Threshold to
Transmitters Enabled (t
WU
)
Receiver Positive or Negative
Threshold to
INVALID
High (t
INVH
)
Receiver Positive or Negative
Threshold to
INVALID
Low (t
INVL
)
www.maximintegrated.com
Figure 5
V
V
V
V
1µA supply current, Figure 5
I
OUT
= 1.6mA
I
OUT
= -1.0mA
Figure 5
Figure 5
Figure 5
0.3
0.4
V
CC
- 0.6
250
1
30
µs
µs
µs
Maxim Integrated | 2
MAX3221/MAX3223/MAX3243
+3V to +5.5V RS-232 Transceivers
with AutoShutdown
Electrical Characteristics (continued)
(V
CC
= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
RECEIVER INPUTS
Input Voltage Range
Input Threshold Low
Input Threshold High
Input Hysteresis
Input Resistance
TRANSMITTER OUTPUTS
Output Voltage Swing
Output Resistance
Output Short-Circuit Current
Output Leakage Current
V
OUT
= ±12V, V
CC
= 0V or 3.0V to 5.5V,
transmitters disabled
All transmitter outputs loaded with 3kΩ to ground
V
CC
= V+ = V- = 0V, transmitter output = ±2V
±5.0
300
±5.4
10M
±35
±60
±25
V
Ω
mA
µA
T
A
= +25°C
3
T
A
= +25°C
T
A
= +25°C
V
CC
= 3.3V
V
CC
= 5.0V
V
CC
= 3.3V
V
CC
= 5.0V
-25
0.6
0.8
1.2
1.5
1.5
1.8
0.3
5
7
2.4
2.4
25
V
V
V
V
kΩ
CONDITIONS
MIN
TYP
MAX
UNITS
MOUSE DRIVEABILITY
(MAX3243)
Transmitter Output Voltage
TIMING CHARACTERISTICS
Maximum Data Rate
Receiver Propagation Delay
Receiver Output Enable Time
Receiver Output Disable Time
Transmitter Skew
Receiver Skew
R
L
= 3kΩ, C
L
= 1000pF, one transmitter switching
Receiver input to receiver output,
C
L
= 150pF
Normal operation
Normal operation
⏐
t
PHL
- t
PLH
⏐
⏐
t
PHL
- t
PLH
⏐
V
CC
= 3.3V,
R
L
= 3kΩ to 7kΩ,
T
A
= +25°C,
measured from +3V to
-3V or -3V to +3V
MAX3221/MAX3223
MAX3243
MAX3221/MAX3223
MAX3243
C
L
= 200pF to 2500pF
4
t
PHL
t
PLH
120
235
0.3
0.3
200
200
200
200
100
100
8.0
500
30
V/µs
C
L
= 200pF to 1000pF
6
30
1000
kbps
µs
ns
ns
ns
ns
T1IN = T2IN = GND, T3IN = V
CC
,
T3OUT loaded with 3kΩ to GND, T1OUT and
T2OUT loaded with 2.5mA each
±5
V
Transition-Region Slew Rate
Note 2:
C1–C4 = 0.1µF, tested at 3.3V ±10%. C1 = 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%.
www.maximintegrated.com
Maxim Integrated | 3
MAX3221/MAX3223/MAX3243
+3V to +5.5V RS-232 Transceivers
with AutoShutdown
Typical Operating Characteristics
(V
CC
= +3.3V, 235kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ, T
A
= +25°C, unless otherwise noted.)
MAX3221/MAX3223
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3221/3223-01
MAX3221/MAX3223
SLEW RATE
vs. LOAD CAPACITANCE
20
18
SLEW RATE (V/μs)
16
12
10
8
6
4
2
+SLEW
-SLEW
CU
14
MAX3221/3223-02
MAX3221/MAX3223
SUPPLY CURRENT vs. LOAD CAPACITANCE
WHEN TRANSMITTING DATA
40
35
235kbps
30
25
20
15
10
5
20kbps
120kbps
25
20
15
10
5
0
0
1000
2000
3000
4000
5000
LOAD CAPACITANCE (pF)
)
MAX3221/3223-03
6
5
TRANSMITTER OUTPUT VOLTAGE (V)
4
3
2
1
0
-1
-2
-3
-4
-5
-6
0
1000
2000
3000
22
35
MAX3221 SUPPLY CURRENT (mA)
30
V
OUT+
V
OUT-
FOR DATA RATES UP TO 235kbps
4000
5000
0
150 500 1000
2000
3000
4000
5000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
MAX3243
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3221/3223-04
3 3 SU
(
MAX3243
SLEW RATE
vs. LOAD CAPACITANCE
MAX3221/3223-05
MAX3243
SUPPLY CURRENT vs. LOAD
CAPACITANCE WHEN TRANSMITTING DATA
40
SUPPLY CURRENT (mA)
35
30
25
20
15
10
20kbps
120kbps
235kbps
MAX3221/3223-06
7.5
V
OUT
+
TRANSMITTER OUTPUT VOLTAGE (V)
5.0
2.5
0
-2.5
-5.0
-7.5
0
1000
2000
3000
4000
V
OUT
-
24
22
20
SLEW RATE (V/μs)
18
16
14
12
10
8
6
4
+SLEW
ALL OUTPUTS LOADED WITH 3kΩ +C
L
0.1μF CHARGE-PUMP CAPACITORS
FOR ALL DATA RATES UP TO 235kbps
0
1000
2000
3000
4000
45
1 TRANSMITTER AT 235kbps
2 TRANSMITTERS AT 30kbps
-SLEW
5
0
5000
0
1000
2000
3000
4000
5000
LOAD CAPACITANCE (pF)
5000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
www.maximintegrated.com
Maxim Integrated | 4
MAX3221/MAX3223/MAX3243
+3V to +5.5V RS-232 Transceivers
with AutoShutdown
Pin Description
PIN
MAX3221
1
5
6
7
8
13
11
9
—
10
16
12
4
14
15
3
2
MAX3223
1
5
6
7
9, 16
8, 17
12, 13
10, 15
—
11
20
14
4
18
19
3
2
MAX3243
—
1
2
3
4–8
9, 10, 11
12, 13, 14
15–19
20
21
22
23
24
25
26
27
28
NAME
EN
C2+
C2-
V-
R_IN
T_OUT
T_IN
R_OUT
R2OUTB
INVALID
FORCEOFF
FORCEON
C1-
GND
V
CC
V+
C1+
FUNCTION
Receiver Enable Control. Drive low for normal operation. Drive high to force
the receiver outputs into a high-Z state.
Positive terminal of inverting charge-pump capacitor
Negative terminal of inverting charge-pump capacitor
-5.5V generated by the charge pump
RS-232 Receiver Inputs
RS-232 Transmitter Outputs
TTL/CMOS Transmitter Inputs
TTL/CMOS Receiver Outputs
Noninverting Receiver Output—active in shutdown
Output of the valid signal detector. Indicates if a valid RS-232 level is pres-
ent on receiver inputs logic “1”.
Drive low to shut down transmitters and on-board power supply. This over-
rides all automatic circuitry and FORCEON (Table 1).
Drive high to override automatic circuitry keeping transmitters on
(FORCEOFF must be high) (Table 1).
Negative terminal of the voltage doubler charge-pump capacitor
Ground
+3.0V to +5.5V Supply Voltage
+5.5V generated by the charge pump
Positive terminal of the voltage doubler charge-pump capacitor
Detailed Description
Dual Charge-Pump Voltage Converter
The MAX3221/MAX3223/MAX3243’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), regardless
of the input voltage (V
CC
) over the +3.0V to +5.5V
range. The charge pumps operate in a 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 Transmitters
The transmitters are inverting level translators that con-
vert CMOS-logic levels to 5.0V EIA/TIA-232 levels. They
guarantee a 120kbps data rate with worst-case loads of
3kΩ in parallel with 1000pF, providing compatibility with
PC-to-PC communication software (such as Laplink™).
Typically, the MAX3221/MAX3223/MAX3243 can oper-
ate at data rates of 235kbps. Transmitters can be paral-
leled to drive multiple receivers or mice (MAX3243).
Figure 1 shows a complete system connection.
When
FORCEOFF
is driven to ground, or the Auto-
Shutdown circuitry senses invalid voltage levels at all
receiver inputs, the transmitters are disabled and the
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