MAX3221
SLLS348P – JUNE 1999 – REVISED JULY 2021
MAX3221 3-V to 5.5-V RS-232 Line Driver and Receiver
With ±15-kV ESD Protection
1 Features
3 Description
•
The MAX3221 device consists of one line driver, one
line receiver with dedicated enable pin, and a dual
charge-pump circuit with ±15-kV ESD protection pin
to pin (serial-port connection pins, including GND).
The device meets the requirements of TIA/EIA-232F and provides the electrical interface between
an asynchronous communication controller and the
serial-port connector. The charge pump and four small
external capacitors allow operation from a single
3-V to 5.5-V supply. These devices operate at data
signaling rates up to 250 kbps and a maximum of
30-V/μs driver output slew rate.
•
•
•
•
•
•
•
•
•
RS-232 Bus-pin ESD protection exceeds
±15 kV using human body model (HBM)
Meets or exceeds the requirements of
TIA/EIA-232-F and ITU V.28 standards
Operates with 3-V to 5.5-V VCC supply
Operates up to 250 kbps
One driver and one receiver
Low standby current: 1 μA typical
External capacitors: 4 × 0.1 μF
Accepts 5-V logic input with 3.3-V supply
Alternative high-speed pin-compatible
device (1 Mbps)
– SNx5C3221
Automatic power-down feature automatically
disables drivers for power savings
Flexible control options for power management
are available when the serial port is inactive.
The automatic power-down feature functions when
FORCEON is low and FORCEOFF is high. During
this mode of operation, if the device does not sense a
valid
RS-232 signal on the receiver input, the driver output
is disabled and the supply current is reduced to 1 μA.
The INVALID output notifies the user if an RS-232
signal is present at the receiver input.
2 Applications
•
•
•
•
•
•
•
•
•
Industrial PCs
Wired networking
Data center and enterprise computing
Battery-powered systems
PDAs
Notebooks
Laptops
Palmtop PCs
Hand-held equipment
Device Information
PART NUMBER
MAX3221
(1)
PACKAGE(1)
BODY SIZE (NOM)
SSOP (DB) (32)
6.20 mm × 5.30 mm
TSSOP (PW) (32)
5.00 mm × 4.40 mm
For all available packages, see the orderable addendum at
the end of the data sheet.
spacer
3.3 V, 5 V
POWER
EN [RX]
FORCEON
APD
FORCEOFF
DIN
1
1
TX
DOUT
RS232
1
ROUT
INVALID
RX
1
RIN
RS232
STATUS
Simplified Diagram
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
MAX3221
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SLLS348P – JUNE 1999 – REVISED JULY 2021
Table of Contents
1 Features............................................................................1
2 Applications..................................................................... 1
3 Description.......................................................................1
4 Revision History.............................................................. 2
5 Pin Configuration and Functions...................................3
6 Specifications.................................................................. 4
6.1 Absolute Maximum Ratings........................................ 4
6.2 ESD Ratings............................................................... 4
6.3 Recommended Operating Conditions.........................4
6.4 Thermal Information....................................................5
6.5 Electrical Characteristics – Power.............................. 5
6.6 Electrical Characteristics – Driver............................... 5
6.7 Electrical Characteristics – Receiver.......................... 6
6.8 Electrical Characteristics – Status.............................. 6
6.9 Switching Characteristics – Driver.............................. 6
6.10 Switching Characteristics – Receiver........................7
6.11 Switching Characteristics – Status............................7
6.12 Typical Characteristics.............................................. 7
7 Parameter Measurement Information............................ 8
8 Detailed Description...................................................... 11
8.1 Overview................................................................... 11
8.2 Functional Block Diagram......................................... 11
8.3 Feature Description...................................................11
8.4 Device Functional Modes..........................................12
9 Application and Implementation.................................. 13
9.1 Application Information............................................. 13
9.2 Typical Application.................................................... 13
10 Power Supply Recommendations..............................14
11 Layout........................................................................... 15
11.1 Layout Guidelines................................................... 15
11.2 Layout Example...................................................... 15
12 Device and Documentation Support..........................16
12.1 Support Resources................................................. 16
12.2 Trademarks............................................................. 16
12.3 Electrostatic Discharge Caution..............................16
12.4 Glossary..................................................................16
13 Mechanical, Packaging, and Orderable
Information.................................................................... 16
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision O (June 2015) to Revision P (July 2021)
Page
• Changed the Applications list............................................................................................................................. 1
• Changed the values in the Thermal Information table for DB and PW packages...............................................5
Changes from Revision N (January 2014) to Revision O (June 2015)
Page
• Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device
Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout
section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information
section ............................................................................................................................................................... 1
Changes from Revision M (March 2004) to Revision N (January 2013)
Page
• Updated document to new TI data sheet format - no specification changes...................................................... 1
• Deleted Ordering Information table.....................................................................................................................1
2
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5 Pin Configuration and Functions
EN
C1+
V+
C1−
C2+
C2−
V−
RIN
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
FORCEOFF
VCC
GND
DOUT
FORCEON
DIN
INVALID
ROUT
Figure 5-1. DB or PW Package, 16-Pin SSOP or TSSOP, Top View
Table 5-1. Pin Functions
PIN
NAME
NO.
I/O
DESCRIPTION
C1+
2
C2+
5
C1–
4
C2–
6
DIN
11
I
Driver input
DOUT
13
O
RS-232 driver output
EN
1
I
Low input enables receiver ROUT output. High input sets ROUT to high impedance.
FORCEOFF
16
I
Automatic power-down control input
FORCEON
12
I
Automatic power-down control input
GND
14
—
Ground
INVALID
10
O
Invalid output pin. Output low when all RIN inputs are unpowered.
RIN
8
I
RS-232 receiver input
ROUT
9
O
Receiver output
VCC
15
—
3-V to 5.5-V supply voltage
V+
3
O
5.5-V supply generated by the charge pump
V–
7
O
–5.5-V supply generated by the charge pump
—
Positive terminals of the voltage-doubler charge-pump capacitors
—
Negative terminals of the voltage-doubler charge-pump capacitors
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6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)(1)
MIN
MAX
VCC to GND
–0.3
6
V+ to GND
–0.3
7
V– to GND
0.3
–7
V+ + |V–|(2)
VI
Input voltage
VO
Output voltage
TJ
Junction temperature(3)
Tstg
Storage temperature range
(1)
(2)
(3)
UNIT
V
13
DIN, EN, FORCEOFF , and FORCEON to GND
–0.3
6
RIN to GND
V
±25
DOUT to GND
±13.2
ROUT to GND
–0.3
VCC + 0.3
150
–65
V
°C
150
Operation outside the Absolute Maximum Ratings may cause permanent device damage. Absolute Maximum Ratings do not imply
functional operation of the device at these or any other conditions beyond those listed under Recommended Operating Conditions.
If used outside the Recommended Operating Conditions but within the Absolute Maximum Ratings, the device may not be fully
functional, and this may affect device reliability, functionality, performance, and shorten the device lifetime.
V+ and V– can have maximum magnitudes of 7 V, but their absolute difference cannot exceed 13 V.
Maximum power dissipation is a function of TJ(max), RθJA, and TA. The maximum allowable power dissipation at any allowable
ambient temperature is PD = (TJ(max) – TA) / RθJA. Operating at the absolute maximum TJ of 150°C can affect reliability.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human body model (HBM), per ANSI/
ESDA/JEDEC JS-001(1)
All pins except 8, 13
UNIT
±3000
Pins 8, 13
±15,000
Charged-device model (CDM), per JEDEC specification JESD22C101(2)
V
±1500
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
(see Figure 9-1)(1)
VCC = 3.3 V
Supply voltage
VCC = 5 V
VIH
Driver high-level input voltage
DIN, FORCEOFF,
FORCEON, EN
VIL
Driver low-level input voltage
DIN, FORCEOFF,
FORCEON, EN
Driver input voltage
DIN, FORCEOFF,
FORCEON, EN
VI
VCC = 3.3 V
VCC = 5 V
(1)
4
Operating free-air temperature
NOM
MAX
3
3.3
3.6
4.5
5
5.5
2
MAX3221C
MAX3221I
UNIT
V
V
2.4
0.8
Receiver input voltage
TA
MIN
0
5.5
–25
25
0
70
–40
85
V
V
°C
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
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6.4 Thermal Information
MAX3221
THERMAL
METRIC(1)
DB (SSOP)
PW (TSSOP)
16 PINS
16 PINS
UNIT
RθJA
Junction-to-ambient thermal resistance
105.8
110.9
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
51.9
41.7
°C/W
RθJB
Junction-to-board thermal resistance
57.6
57.2
°C/W
ψJT
Junction-to-top characterization parameter
14.1
4.2
°C/W
ψJB
Junction-to-board characterization parameter
56.8
56.6
°C/W
(1)
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report, SPRA953.
6.5 Electrical Characteristics – Power
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(2)
PARAMETER
II
±1
µA
0.3
1
mA
Supply current
No load, FORCEOFF at GND
1
10
No load, FORCEOFF at VCC,
FORCEON at GND,
All RIN are open or grounded
1
10
No load, FORCEOFF and
FORCEON at VCC
Powered off
No load,
VCC = 3.3 V to 5 V
Automatic power-down enabled
(1)
(2)
MAX
±0.01
MIN
Input leakage current FORCEOFF, FORCEON, EN
Automatic power-down
disabled
ICC
TYP(1)
TEST CONDITIONS
UNIT
µA
All typical values are at VCC = 3.3 V or VCC = 5 V, and TA = 25°C.
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
6.6 Electrical Characteristics – Driver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(3)
PARAMETER
TEST CONDITIONS
MIN
TYP(1)
5.4
MAX
UNIT
VOH
High-level output voltage
DOUT at RL = 3 kΩ to GND,
DIN = GND
5
VOL
Low-level output voltage
DOUT at RL = 3 kΩ to GND,
DIN = VCC
–5
IIH
High-level input current
VI = VCC
±0.01
±1
μA
IIL
Low-level input current
VI at GND
±0.01
±1
μA
IOS
Short-circuit output current(2)
rO
Output resistance
Ioff
(1)
(2)
(3)
Output leakage current
V
–5.4
V
VCC = 3.6 V
VO = 0 V
±35
±60
VCC = 5.5 V
VO = 0 V
±35
±60
VCC, V+, and V– = 0 V
VO = ±2 V
FORCEOFF = GND
300
10M
mA
Ω
VO = ±12 V,
VCC = 3 V to 3.6 V
±25
VO = ±12 V,
VCC = 4.5 V to 5.5 V
±25
µA
All typical values are at VCC = 3.3 V or VCC = 5 V, and TA = 25°C.
Short-circuit durations should be controlled to prevent exceeding the device absolute power dissipation ratings, and not more than one
output should be shorted at a time.
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5
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6.7 Electrical Characteristics – Receiver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(2)
PARAMETER
VOH
High-level output voltage
IOH = –1 mA
VOL
Low-level output voltage
IOL = 1.6 mA
VIT+
Positive-going input threshold voltage
VIT–
Negative-going input threshold voltage
TYP(1)
VCC – 0.6
VCC – 0.1
MAX
VCC = 3.3 V
1.5
2.4
VCC = 5 V
1.8
2.4
VCC = 3.3 V
0.6
1.1
VCC = 5 V
0.8
1.4
Vhys
Input hysteresis (VIT+ – VIT–)
Output leakage current
FORCEOFF = 0 V
ri
Input resistance
VI = ±3 V to ±25 V
V
V
V
0.5
3
UNIT
V
0.4
Ioff
(1)
(2)
MIN
TEST CONDITIONS
V
±0.05
±10
µA
5
7
kΩ
All typical values are at VCC = 3.3 V or VCC = 5 V, and TA = 25°C.
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
6.8 Electrical Characteristics – Status
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(2)
PARAMETER
TEST CONDITIONS
VT+(valid)
Receiver input threshold for INVALID high- FORCEON = GND,
level output voltage
FORCEOFF = VCC
VT–(valid)
Receiver input threshold for INVALID high- FORCEON = GND,
level output voltage
FORCEOFF = VCC
–2.7
VT(invalid)
Receiver input threshold for INVALID lowlevel output voltage
FORCEON = GND,
FORCEOFF = VCC
–0.3
VOH
INVALID high-level output voltage
IOH = –1 mA,
FORCEON = GND,
FORCEOFF = VCC
VCC – 0.6
VOL
INVALID low-level output voltage
IOH = –1 mA,
FORCEON = GND,
FORCEOFF = VCC
(1)
(2)
TYP(1)
MIN
MAX
2.7
UNIT
V
V
0.3
V
V
0.4
V
All typical values are at VCC = 3.3 V or VCC = 5 V, and TA = 25°C.
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
6.9 Switching Characteristics – Driver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(3)
PARAMETER
Maximum data rate
CL = 1000 pF, RL = 3 kΩ,
see Figure 7-1
tsk(p)
Pulse skew(2)
CL = 150 to 2500 pF, RL = 3 kΩ to 7 kΩ,
see Figure 7-2
SR(tr)
Slew rate, transition region
(see Figure 7-1)
VCC = 3.3 V,
RL = 3 kΩ to 7 kΩ
(1)
(2)
(3)
6
TEST CONDITIONS
MIN
TYP(1)
150
250
kbps
100
ns
MAX
CL = 150 to 1000 pF
6
30
CL = 150 to 2500 pF
4
30
UNIT
V/μs
All typical values are at VCC = 3.3 V or VCC = 5 V, and TA = 25°C.
Pulse skew is defined as |tPLH − tPHL| of each channel of the same device.
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
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6.10 Switching Characteristics – Receiver
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(3)
PARAMETER
TEST CONDITIONS
MIN
TYP(1)
MAX
UNIT
tPLH
Propagation delay time, low- to high-level output
CL = 150 pF,
see Figure 7-3
150
ns
tPHL
Propagation delay time, high- to low-level output
CL = 150 pF,
see Figure 7-3
150
ns
ten
Output enable time
CL = 150 pF, RL = 3 kΩ,
see Figure 7-4
200
ns
tdis
Output disable time
CL = 150 pF, RL = 3 kΩ,
see Figure 7-4
200
ns
tsk(p)
Pulse skew(2)
See Figure 7-3
50
ns
(1)
(2)
(3)
All typical values are at VCC = 3.3 V or VCC = 5 V, and TA = 25°C.
Pulse skew is defined as |tPLH − tPHL| of each channel of the same device.
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
6.11 Switching Characteristics – Status
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)(2)
PARAMETER
MIN
TYP(1)
MAX
UNIT
tvalid
Propagation delay time, low- to high-level output
1
µs
tinvalid
Propagation delay time, high- to low-level output
30
µs
ten
Supply enable time
100
µs
(1)
(2)
All typical values are at VCC = 3.3 V or VCC = 5 V, and TA = 25°C.
Test conditions are C1–C4 = 0.1 μF at VCC = 3.3 V ± 0.3 V; C1 = 0.047 μF, C2–C4 = 0.33 μF at VCC = 5 V ± 0.5 V.
6.12 Typical Characteristics
VCC = 3.3 V
0
6
VOH
VOL
±1
DOUT Voltage (V)
DOUT Voltage (V)
5
4
3
2
1
±2
±3
±4
±5
0
±6
0
5
10
15
20
DOUT Current (mA)
25
0
5
Figure 6-1. DOUT VOH vs Load Current
10
15
20
DOUT Current (mA)
C001
25
C001
Figure 6-2. DOUT VOL vs Load Current
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7 Parameter Measurement Information
3V
Generator
(see Note B)
RS-232
Output
50 Ω
RL
TEST CIRCUIT
0V
tTHL
CL
(see Note A)
3V
FORCEOFF
A.
B.
Input
tTLH
3V
3V
Output
−3 V
−3 V
6V
SR(tr) =
t THL or t TLH
VOH
VOL
VOLTAGE WAVEFORMS
CL includes probe and jig capacitance.
The pulse generator has the following characteristics: PRR = 250 kbps, ZO = 50 Ω, 50% duty cycle, tr ≤ 10 ns, tf ≤ 10 ns.
Figure 7-1. Driver Slew Rate
3V
Generator
(see Note B)
RS-232
Output
50 Ω
RL
Input
0V
CL
(see Note A)
tPHL
tPLH
VOH
3V
FORCEOFF
50%
50%
Output
VOL
TEST CIRCUIT
A.
B.
1.5 V
1.5 V
VOLTAGE WAVEFORMS
CL includes probe and jig capacitance.
The pulse generator has the following characteristics: PRR = 250 kbps, ZO = 50 Ω, 50% duty cycle, tr ≤ 10 ns, tf ≤ 10 ns.
Figure 7-2. Driver Pulse Skew
3 V or 0 V
FORCEON
3V
Input
1.5 V
1.5 V
−3 V
Output
Generator
(see Note B)
50 Ω
3V
FORCEOFF
tPHL
CL
(see Note A)
tPLH
VOH
50%
Output
50%
VOL
TEST CIRCUIT
A.
B.
VOLTAGE WAVEFORMS
CL includes probe and jig capacitance.
The pulse generator has the following characteristics: ZO = 50 Ω, 50% duty cycle, tr ≤ 10 ns, tf ≤ 10 ns.
Figure 7-3. Receiver Propagation Delay Times
8
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3V
Input
3 V or 0 V
FORCEON
VCC
S1
1.5 V
GND
0V
tPZH
(S1 at GND)
tPHZ
(S1 at GND)
RL
3 V or 0 V
1.5 V
VOH
Output
50%
Output
CL
(see Note A)
EN
Generator
(see Note B)
50 Ω
0.3 V
tPZL
(S1 at VCC)
tPLZ
(S1 at VCC)
0.3 V
Output
50%
VOL
TEST CIRCUIT
A.
B.
C.
D.
VOLTAGE WAVEFORMS
CL includes probe and jig capacitance.
The pulse generator has the following characteristics: ZO = 50 Ω, 50% duty cycle, tr ≤ 10 ns, tf ≤ 10 ns.
tPLZ and tPHZ are the same as tdis.
tPZL and tPZH are the same as ten.
Figure 7-4. Receiver Enable and Disable Times
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2.7 V
2.7 V
0V
Receiver
Input
ROUT
Generator
(see Note B)
3V
0V
−2.7 V
−2.7 V
−3 V
50 Ω
tvalid
tinvalid
VCC
Autopowerdown
INVALID
CL = 30 pF
(see Note A)
FORCEOFF
FORCEON
DIN
DOUT
INVALID
Output
50% VCC
50% VCC
0V
ten
V+
≈V+
Supply
Voltages
0.3 V
VCC
0V
0.3 V
V−
TEST CIRCUIT
≈V−
VOLTAGE WAVEFORMS
Valid RS-232 Level, INVALID High
2.7 V
Indeterminate
0.3 V
0V
If Signal Remains Within This Region
For More Than 30 µs, INVALID Is Low†
−0.3 V
Indeterminate
−2.7 V
Valid RS-232 Level, INVALID High
† Auto-powerdown disables drivers and reduces supply
current to 1 µA.
Figure 7-5. INVALID Propagation Delay Times and Driver Enabling Time
10
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8 Detailed Description
8.1 Overview
The MAX3221 device is a one-driver and one-receiver RS-232 interface device. All RS-232 inputs and outputs
are protected to ±15 kV using the Human Body Model. The charge pump requires only four small 0.1-μF
capacitors for operation from a 3.3-V supply. The MAX3221 is capable of running at data rates up to 250 kbps,
while maintaining RS-232-compliant output levels.
Automatic power-down can be disabled when FORCEON and FORCEOFF are high. With automatic powerdown plus enabled, the device activates automatically when a valid signal is applied to any receiver input. The
device can automatically power down the driver to save power when the RIN input is unpowered.
INVALID is high (valid data) if receiver input voltage is greater than 2.7 V or less than –2.7 V, or has been
between –0.3 V and 0.3 V for less than 30 μs. INVALID is low (invalid data) if receiver input voltages are
between –0.3 V and 0.3 V for more than 30 μs. Refer to Figure 7-5 for receiver input levels.
8.2 Functional Block Diagram
3.3V, 5V
POWER
EN [RX]
FORCEON
APD
FORCEOFF
DIN
ROUT
INVALID
1
1
TX
RX
1
DOUT
RS232
1
RIN
RS232
STATUS
8.3 Feature Description
8.3.1 Power
The power block increases, inverts, and regulates voltage at V+ and V- pins using a charge pump that requires
four external capacitors. Auto-power-down feature for driver is controlled by FORCEON and FORCEOFF inputs.
Receiver is controlled by EN input. See Table 8-1 and Table 8-2
When MAX3221 is unpowered, it can be safely connected to an active remote RS232 device.
8.3.2 RS232 Driver
One driver interfaces standard logic level to RS232 levels. DIN input must be valid high or low.
8.3.3 RS232 Receiver
One receiver interfaces RS232 levels to standard logic levels. An open input will result in a high output on ROUT.
RIN input includes an internal standard RS232 load. A logic high input on the EN pin will shutdown the receiver
output.
8.3.4 RS232 Status
The INVALID output goes low when RIN input is unpowered for more than 30 μs. The INVALID output goes high
when receiver has a valid input. The INVALID output is active when Vcc is powered irregardless of FORCEON
and FORCEOFF inputs (see Table 8-3).
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MAX3221
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SLLS348P – JUNE 1999 – REVISED JULY 2021
8.4 Device Functional Modes
Table 8-1, Table 8-2, and Table 8-3 show the behavior of the driver, receiver, and INVALID(activelow) features
under all possible relevant combinations of inputs.
Table 8-1. Driver(1)
INPUTS
OUTPUT
DIN
(1)
FORCEON
VALID RIN RS-232
LEVEL
FORCEOFF
DRIVER STATUS
DOUT
X
X
L
X
Z
Powered off
Normal operation with
automatic power down disabled
L
H
H
X
H
H
H
H
X
L
L
L
H
Yes
H
H
L
H
Yes
L
L
L
H
No
Z
H
L
H
No
Z
Normal operation with
automatic power down enabled
Powered off by
automatic power down feature
H = high level, L = low level, X = irrelevant, Z = high impedance, Yes = |RIN| > 2.7 V, No = |RIN|