Low Power, 3.3 V, RS-232
Line Drivers/Receivers
ADM3202/ADM3222/ADM1385
FEATURES
460 kbps data rate
Specified at 3.3 V
Meets EIA-232E specifications
0.1 μF charge pump capacitors
Low power shutdown (ADM3222 and ADM1385)
PDIP, SOIC_N, SOIC_W, SSOP, and TSSOP options
Upgrade for MAX3222/MAX3232 and LTC1385
ESD protection to IEC 1000-4-2 (801.2)
on RS-232 pins (ADM3202 only)
±8 kV: contact discharge
±15 kV: air gap discharge
FUNCTIONAL BLOCK DIAGRAMS
+3.3V INPUT
C3
0.1µF
6.3V
C4
0.1µF
10V
EIA/TIA-232
OUTPUTS
+
+
CMOS
INPUTS
T1
IN
T2
IN
R1
OUT
R2
OUT
T1
T2
R1
R2
GND
T1
OUT
T2
OUT
R1
IN
R2
IN
CMOS
OUTPUTS
ADM3202
*INTERNAL 5kΩ PULL-DOWN RESISTOR
ON EACH RS-232 INPUT
00071-001
APPLICATIONS
General-purpose RS-232 data link
Portable instruments
Printers, palmtop computers, PDAs
Figure 1.
+3.3V INPUT
0.1µF +
10V
0.1µF +
10V
T1
IN
T2
IN
R1
OUT
R2
OUT
EN
GND
C1+ +3.3V TO +6.6V V
CC
VOLTAGE
C1–
V+
DOUBLER
C2+ +6.6V TO –6.6V
VOLTAGE
C2–
INVERTER
T1
T2
R1
R2
SD
V–
+
C3
0.1µF
6.3V
C4
0.1µF
10V
EIA/TIA-232
OUTPUTS
GENERAL DESCRIPTION
The ADM3202/ADM3222/ADM1385 transceivers are high
speed, 2-channel RS-232/V.28 interface devices that operate
from a single 3.3 V power supply. Low power consumption and
a shutdown facility (ADM3222/ADM1385) make them ideal for
battery-powered portable instruments.
The ADM3202/ADM3222/ADM1385 parts conform to the
EIA-232E and CCITT V.28 specifications and operate at data
rates up to 460 kbps.
Four external 0.1 μF charge pump capacitors are used for the
voltage doubler/inverter, permitting operation from a single
3.3 V supply.
The ADM3222 contains additional enable and shutdown
circuitry. The EN input can be used to three-state the receiver
outputs. The SD input is used to power down the charge pump
and transmitter outputs, reducing the quiescent current to less
than 0.5 μA. The receivers remain enabled during shutdown
unless disabled using EN.
The ADM1385 contains a driver disable mode and a complete
shutdown mode.
The ADM3202 is available in a 16-lead PDIP, SOIC_W, and
SOIC_N, as well as a space-saving 16-lead TSSOP. The ADM3222
is available in 18-lead PDIP and SOIC_W and in 20-lead SSOP
and TSSOP. The ADM1385 is available in a 20-lead SSOP,
which is pin-compatible with the LTC1385 CG.
Rev. E
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
CMOS
INPUTS
T1
OUT
T2
OUT
R1
IN
R2
IN
CMOS
OUTPUTS
ADM3222
*INTERNAL 5kΩ PULL-DOWN RESISTOR
ON EACH RS-232 INPUT
00071-002
Figure 2.
+3.3V INPUT
+
0.1µF +
10V
0.1µF +
10V
T1
IN
T2
IN
R1
OUT
R2
OUT
DD
GND
C1+ +3.3V TO +6.6V V
CC
VOLTAGE
C1–
V+
DOUBLER
C2+ +6.6V TO –6.6V
VOLTAGE
C2–
INVERTER
T1
T2
R1
R2
SD
00071-003
V–
+
C4
0.1µF
10V
T1
OUT
T2
OUT
R1
IN
R2
IN
CMOS
INPUTS
CMOS
OUTPUTS
ADM1385
*INTERNAL 5kΩ PULL-DOWN RESISTOR
ON EACH RS-232 INPUT
Figure 3.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©1998–2011 Analog Devices, Inc. All rights reserved.
+
+
0.1µF +
10V
C2+ +6.6V TO –6.6V
VOLTAGE
C2–
INVERTER
V–
+
+
0.1µF +
10V
C1+ +3.3V TO +6.6V V
CC
VOLTAGE
C1–
V+
DOUBLER
C5
0.1µF
EIA/TIA-232
INPUTS*
C5
0.1µF
EIA/TIA-232
INPUTS*
C3
0.1µF
10V
C5
0.1µF
EIA/TIA-232
OUTPUTS
EIA/TIA-232
INPUTS*
ADM3202/ADM3222/ADM1385
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagrams............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
ESD Caution.................................................................................. 4
Pin Configurations and Function Descriptions ........................... 5
Pin Configurations (N, RN, RU, and RW Packages)................5
Pin Configurations (RS and RU Packages)................................5
Typical Performance Characteristics ..............................................6
General Description..........................................................................8
Circuit Description .......................................................................8
High Baud Rate..............................................................................9
Outline Dimensions ....................................................................... 10
Ordering Guide .......................................................................... 14
REVISION HISTORY
7/11—Rev. D to Rev. E
Changes to Figure 3.......................................................................... 1
Changes to Table 2............................................................................ 4
Changes to Figure 17........................................................................ 8
Updated Outline Dimensions ....................................................... 10
Changes to Ordering Guide .......................................................... 14
8/06—Rev. C to Rev. D
Changes to Table 1............................................................................ 3
Updated Outline Dimensions ....................................................... 10
Changes to Ordering Guide .......................................................... 12
9/05—Rev. B to Rev. C
Updated Outline Dimensions ....................................................... 10
Changes to Ordering Guide .......................................................... 12
12/01—Rev. A to Rev. B
Changes to Specifications Page....................................................... 2
Rev. E | Page 2 of 16
ADM3202/ADM3222/ADM1385
SPECIFICATIONS
V
CC
= 3.3 V ± 0.3 V, C1 to C4 = 0.1 μF. All specifications T
MIN
to T
MAX
, unless otherwise noted.
Table 1.
Parameter
DC CHARACTERISTICS
Operating Voltage Range
V
CC
Power Supply Current
Shutdown Supply Current
LOGIC
Input Logic Threshold Low, V
INL
Input Logic Threshold High, V
INH
CMOS Output Voltage Low, V
OL
CMOS Output Voltage High, V
OH
Logic Pull-Up Current
Output Leakage Current
RS-232 RECEIVER
EIA-232 Input Voltage Range
EIA-232 Input Threshold Low
EIA-232 Input Threshold High
EIA-232 Input Hysteresis
EIA-232 Input Resistance
RS-232 TRANSMITTER
Output Voltage Swing (RS-232)
Output Voltage Swing (RS-562)
Transmitter Output Resistance
RS-232 Output Short-Circuit Current
Output Leakage Current
TIMING CHARACTERISTICS
Maximum Data Rate
Receiver Propagation Delay
TPHL
TPLH
Transmitter Propagation Delay
Receiver Output Enable Time
Receiver Output Disable Time
Transmitter Skew
Receiver Skew
Transition Region Slew Rate
1
Min
3.0
Typ
3.3
1.3
8
0.01
Max
5.5
3
12
0.5
0.8
Unit
V
mA
mA
μA
V
V
V
V
μA
μA
V
V
V
V
kΩ
V
V
Ω
mA
μA
kbps
Test Conditions/Comments
No load
R
L
= 3 kΩ to GND
2.0
0.4
V
CC
− 0.6
5
10
±10
+30
1.2
1.6
0.4
5
±5.2
2.4
7
T
IN
T
IN
I
OUT
= 1.6 mA
I
OUT
= −1 mA
T
IN
= GND to V
CC 1
Receivers disabled
−30
0.6
3
±5.0
±3.7
300
V
CC
= 3.3 V, all transmitter outputs loaded with 3 kΩ to ground
V
CC
= 3.0 V
V
CC
= 0 V, V
OUT
= ±2 V
SD = low, V
OUT
= 12 V
V
CC
= 3.3 V, R
L
= 3 kΩ to 7 kΩ, C
L
= 50 pF to 1000 pF, one
Tx switching
±15
±25
460
5.5
0.4
0.4
0.3
200
200
30
300
10
1
1
1.2
30
μs
μs
μs
ns
ns
ns
ns
V/μs
R
L
= 3 kΩ, C
L
= 1000 pF
Measured from +3 V to −3 V or −3 V to +3 V, V
CC
= +3.3 V;
R
L
= 3 kΩ, C
L
= 1000 pF, T
A
= 25°C
ADM1385: Input leakage current typically −10 μA when T
IN
= GND.
Rev. E | Page 3 of 16
ADM3202/ADM3222/ADM1385
ABSOLUTE MAXIMUM RATINGS
T
A
= 25°C, unless otherwise noted.
Table 2.
Parameter
V
CC
V+
V−
Input Voltages
T
IN
R
IN
Output Voltages
T
OUT
R
OUT
Short-Circuit Duration
T
OUT
Power Dissipation (Derates 6 mW/°C
above 50°C)
Thermal Impedance, θ
JA
N-16/N-18 (2-Layer Test Board)
RW-16/RW-18 (4-Layer Test Board)
R-16 (4-Layer Test Board)
RU-16 (4-Layer Test Board)
RU-20 (4-Layer Test Board)
RS-20 (4-Layer Test Board)
Operating Temperature Range
Industrial (A Version)
Storage Temperature Range
Lead Temperature
(Soldering, 10 sec)
Rating
−0.3 V to +6 V
(V
CC
− 0.3 V) to +14 V
+0.3 V to –14 V
−0.3 V to (V+, +0.3 V)
±30 V
±15 V
−0.3 V to (V
CC
+ 0.3 V)
Continuous
450 mW
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
117°C/W
56°C/W
81°C/W
113°C/W
110°C/W
83°C/W
−40°C to +85°C
−65°C to +150°C
JEDEC industry
standard J-STD-020
Rev. E | Page 4 of 16
ADM3202/ADM3222/ADM1385
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
PIN CONFIGURATIONS (N, R, RU, AND RW PACKAGES)
C1+
V+
C1–
C2+
C2–
V–
T2
OUT
R2
IN
1
2
3
4
5
6
7
8
16
15
V
CC
GND
T1
OUT
R1
IN
R1
OUT
T1
IN
00071-004
EN
C1+
V+
C1–
C2+
C2–
V–
T2
OUT
R2
IN
1
2
3
4
5
6
7
8
9
18
17
SD
V
CC
GND
T1
OUT
R1
IN
R1
OUT
T1
IN
R2
OUT
00071-005
ADM3202
TOP VIEW
(Not to Scale)
14
13
12
11
10
9
ADM3222
TOP VIEW
(Not to Scale)
16
15
14
13
12
11
10
T2
IN
R2
OUT
T2
IN
Figure 4. N, R, RU, and RW Packages Pin Configuration
Figure 5. N and RW Packages Pin Configuration
PIN CONFIGURATIONS (RS AND RU PACKAGES)
EN
1
C1+
2
V+
3
C1–
4
20
19
SD
V
CC
GND
T1
OUT
R1
IN
R1
OUT
NC
T1
IN
T2
IN
00071-006
DD
1
C1+
2
V+
3
C1–
4
C2+
5
C2–
6
V–
7
T2
OUT 8
R2
IN 9
NC
10
NC = NO CONNECT
20
SD
19
V
CC
18
GND
17
T1
OUT
16
R1
IN
15
R1
OUT
14
T1
IN
13
T2
IN
12
R2
OUT
00071-007
ADM3222
(SSOP/TSSOP)
TOP VIEW
(Not to Scale)
18
17
16
15
14
13
12
11
ADM1385
(SSOP)
TOP VIEW
(Not to Scale)
C2+
5
C2–
6
V–
7
T2
OUT 8
R2
IN 9
R2
OUT 10
11
NC
NC
NC = NO CONNECT
Figure 6. RS and RU Packages Pin Configuration
Figure 7. RS Package Pin Configuration
Table 3. Pin Function Descriptions
Mnemonic
V
CC
V+
V–
GND
C1+, C1–
C2+, C2–
Tx
IN
Tx
OUT
Rx
IN
Rx
OUT
EN
SD
SD
DD
NC
Description
Power Supply Input (3.3 V ± 0.3 V).
Internally Generated Positive Supply (+6 V nominal).
Internally Generated Negative Supply (−6 V nominal).
Ground Pin. Must be connected to 0 V.
External Capacitor 1 is connected between these pins. A 0.1 μF capacitor is recommended but larger capacitors up to 47 μF
can be used.
External Capacitor 2 is connected between these pins. A 0.1 μF capacitor is recommended but larger capacitors up to 47 μF
can be used.
Transmitter (Driver) Inputs. These inputs accept TTL/CMOS levels.
Transmitter (Driver) Outputs. These are RS-232 signal levels (typically ±9 V).
Receiver Inputs. These inputs accept RS-232 signal levels. An internal 5 kΩ pull-down resistor to GND is connected on each input.
Receiver Outputs. These are CMOS output logic levels.
(ADM3222 only) Receiver Enable. Active low. When low, the receiver outputs are enabled. When high, they are three-stated.
(ADM3222 only) Shutdown Control. Active low. When low, the charge pump is shut down and the transmitter outputs
are disabled.
(ADM1385 only) Shutdown Control. When low, the charge pump is shut down and all transmitters and receivers are disabled.
(ADM1385 only) Driver Disable. When low, the charge pump is turned off and the transmitters are disabled. The receivers
remain active.
No Connect.
Rev. E | Page 5 of 16