19-1845; Rev 1; 9/01
2.5V, ±15kV ESD-Protected RS-232
Transceivers for PDAs and Cell Phones
General Description
The MAX3388E/MAX3389E are 2.5V-powered EIA/TIA-
232 and V.28/V.24 communications interfaces with low
power requirements, high data-rate capabilities, and
enhanced electrostatic discharge (ESD) protection. The
MAX3388E/MAX3389E have two receivers and three
transmitters. All RS-232 inputs and outputs are protected
to ±15kV using the IEC 1000-4-2 Air-Gap Discharge
method, ±8kV using the IEC 1000-4-2 Contact Discharge
method, and ±15kV using the Human Body Model.
In addition to the traditional RS-232 I/O, these devices have
dedicated logic-level I/O pins for additional device-to-
device handshaking. During shutdown the logic-level I/O
pins are active for the MAX3389E. An internal 62Ω switch is
provided to switch power to external circuitry or modules.
A proprietary low-dropout transmitter output stage
enables RS-232 compatible performance from a +2.35V
to +3.0V supply with a dual charge pump. The charge
pump requires only four small 0.1µF capacitors for oper-
ation from a +2.5V supply. The MAX3388E/MAX3389E
are capable of running at data rates up to 460kbps while
maintaining RS-232-compatible output levels.
The MAX3388E/MAX3389E have a unique V
L
pin that
allows interoperation in mixed-logic voltage systems.
Both input and output logic levels are pin programma-
ble through the V
L
pin. The MAX3388E/MAX3389E are
available in a space-saving TSSOP package.
Features
o
V
L
Pin for Compatibility with Mixed-Voltage
Systems
o
Additional I/O for Hot-Sync Applications
o
±15kV ESD Protection on Rx Inputs, Tx Outputs,
LIN, and SWIN
o
Low 300µA Supply Current
o
Guaranteed 460kbps Data Rate
o
1µA Low-Power Shutdown
o
Integrated Switch for Powering Remote Circuitry
o
Flow-Through Pinout
o
L
OUT
Active During Shutdown (MAX3389E)
MAX3388E/MAX3389E
Applications
Subnotebook/Palmtop Computers
PDAs and PDA Cradles
Cell Phone Data Cables
Battery-Powered Equipment
Hand-Held Equipment
Peripherals
Ordering Information
PART
TEMP. RANGE
0°C to +70°C
-40°C to +85°C
0°C to +70°C
-40°C to +85°C
PIN-PACKAGE
24 TSSOP
24 TSSOP
24 TSSOP
24 TSSOP
MAX3388ECUG
MAX3388EEUG
MAX3389ECUG
Typical Operating Circuit
+2.5V
C
BYPASS
C1
0.1µF
1 C1+
3
4
C2
0.1µF
5
C1-
C2+
C2-
T1OUT
21
8 T2IN
9 T3IN
V
L
13 R1OUT
R1IN
18
5kΩ
V
L
12 R2OUT
10 LOUT
R2IN
17
5kΩ
LIN
16
SHDN
11
=
±15kV
ESD PROTECTION
SWOUT
30kΩ
SWIN 15
T2OUT
20
T3OUT
19
RS-232
I/O
24
SHDN
23
V
CC
14
V
L
V+
2
C3
0.1µF
MAX3389EEUG
MAX3388E
MAX3389E
V-
6
C4
0.1µF
Pin Configuration
TOP VIEW
C1+ 1
V+ 2
C1- 3
C2+ 4
C2- 5
V- 6
T1IN 7
T2IN 8
T3IN 9
LOUT 10
SWOUT 11
R2OUT 12
24 SHDN
23 V
CC
22 GND
21 T1OUT
7 T1IN
MAX3388E
MAX3389E
20 T2OUT
19 T3OUT
18 R1IN
17 R2IN
16 LIN
15 SWIN
14 V
L
13 R1OUT
GND
22
Covered by U.S Patent numbers 4,636,930; 4,679,134;
4,777,577; 4,797,899; 4,809,152; 4,897,774; 4,999,761.
TSSOP
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
