19-2140; Rev 0; 8/01
+2.5V to +5.5V RS-232 Transceivers
in UCSP
General Description
The MAX3228/MAX3229 are +2.5V to +5.5V powered
EIA/TIA-232 and V.28/V.24 communications interfaces
with low power requirements, and high data-rate capa-
bilities, in a chip-scale package (UCSP™).
The MAX3228/MAX3229 achieve a 1µA supply current
with Maxim’s AutoShutdown™ feature. They save
power without changes to existing BIOS or operating
systems by entering low-power shutdown mode when
the RS-232 cable is disconnected, or when the trans-
mitters of the connected peripherals are off.
The transceivers have a proprietary low-dropout trans-
mitter output stage, delivering RS-232 compliant perfor-
mance from a +3.1V to +5.5V supply, and RS-232
compatible performance with a supply voltage as low
as +2.5V. The dual charge pump requires only four
small 0.1µF capacitors for operation from a +3.0V sup-
ply. Each device is guaranteed to run at data rates of
250kbps while maintaining RS-232 output levels.
The MAX3228/MAX3229 offer a separate power-supply
input for the logic interface, allowing configurable logic
levels on the receiver outputs and transmitter inputs.
Operating over a +1.65V to V
CC
range, V
L
provides the
MAX3228/MAX3229 compatibility with multiple logic
families.
The MAX3229 contains one receiver and one transmit-
ter. The MAX3228 contains two receivers and two
transmitters. The MAX3228/MAX3229 are available in
tiny chip-scale packaging and are specified across the
extended industrial temperature range of -40°C to
+85°C.
o
6
✕
5 Chip-Scale Packaging (UCSP)
o
1µA Low-Power AutoShutdown
o
250kbps Guaranteed Data Rate
o
Meets EIA/TIA-232 Specifications Down to +3.1V
o
RS-232 Compatible to +2.5V Allows Operation
from Single Li+ Cell
o
Small 0.1µF Capacitors
o
Configurable Logic Levels
Features
MAX3228/MAX3229
Ordering Information
PART
MAX3228EBV
MAX3229EBV
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
6
✕
5 UCSP*
6
✕
5 UCSP*
*Requires solder temperature profile described in the Absolute
Maximum Ratings section.
*UCSP reliability is integrally linked to the user’s assembly
methods, circuit board material, and environment. Refer to the
UCSP Reliabilitly Notice in the UCSP Reliability section of this
data sheet for more information.
Typical Operating Circuits
2.5V TO 5.5V 1.65V TO 5.5V
0.1µF
C
BYPASS
0.1µF
A1
C1
C1+
C1-
C2+
C2-
V
L
T1OUT
V
L
B6 T2IN
V
L
D6 R1OUT
R1IN
E6
T2OUT E4
E3
RS-232
OUTPUTS
V
CC
A5
V
L
V+
B1
C3
0.1µF
A4
C4
0.1µF
Applications
Personal Digital Assistants
Cell Phone Data Lump Cables
Set-Top Boxes
Hand-Held Devices
Cell Phones
C1
0.1µF
D1
A2
MAX3228
V-
C2
0.1µF
A3
A6 T1IN
TTL/CMOS
INPUTS
Typical Operating Circuits continued at end of data sheet.
Pin Configurations appear at end of data sheet.
TTL/CMOS
OUTPUTS
C6 R2OUT
V
L
5kΩ
R2IN E5
RS-232
INPUTS
5kΩ
UCSP is a trademark of Maxim Integrated Products, Inc.
AutoShutdown is a trademark of Maxim Integrated Products, Inc.
20µA
B5 FORCEON
V
L
V
L
INVALID
20µA
E2
TO POWER-
MANAGEMENT
UNIT
V
L
FORCEOFF C5
GND
E1
________________________________________________________________
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.
+2.5V to +5.5V RS-232 Transceivers
in UCSP
MAX3228/MAX3229
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ...........................................................-0.3V to +6.0V
V+ to GND .............................................................-0.3V to +7.0V
V- to GND ..............................................................+0.3V to -7.0V
V+ to |V-| (Note 1) ................................................................+13V
V
L
to GND..............................................................-0.3V to +6.0V
Input Voltages
T
_
IN, FORCEON,
FORCEOFF
to GND .......-0.3V to (V
L
+ 0.3V)
R
_
IN to GND .....................................................................±25V
Output Voltages
T
_
OUT to GND ...............................................................±13.2V
R
_
OUT to GND ...........................................-0.3V to (V
L
+ 0.3V)
INVALID
to GND......................................-0.3V to (V
CC
+ 0.3V)
Short-Circuit Duration T
_
OUT to GND........................Continuous
Continuous Power Dissipation (T
A
= +70°C)
6
✕
5 UCSP (derate 10.1mW/°C above T
A
= +70°C) ...805mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Bump Temperature (Soldering) (Note 2)
Infrared (15s) ...............................................................+200°C
Vapor Phase (20s) .......................................................+215°C
Note 1:
V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
Note 2:
This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device
can be exposed to during board level solder attach and rework. This limit permits only the use of the solder profiles recom-
mended in the industry-standard specification, JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and convection reflow. Pre-
heating is required. Hand or wave soldering is not allowed.
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
= +2.5V to +5.5V, V
L
= +1.65V to +5.5V, C1–C4 = 0.1µF, tested at +3.3V ±10%, T
A
= T
MIN
to T
MAX
. Typical values are at T
A
=
+25°C, unless otherwise noted.) (Note 3)
PARAMETER
DC CHARACTERISTICS
V
L
Input Voltage Range
V
CC
Supply Current,
AutoShutdown
V
L
FORCEON = GND
FORCEOFF
= V
L
, all R
IN
open
FORCEOFF
= GND
FORCEON,
FORCEOFF
floating
V
CC
Supply Current,
AutoShutdown Disabled
V
L
Supply Current
LOGIC INPUTS
Pullup Currents
Input Logic Low
Input Logic High
Transmitter Input Hysteresis
Input Leakage Current
RECEIVER OUTPUTS
Output Leakage Currents
Output Voltage Low
Output Voltage High
R_OUT, receivers disabled,
FORCEOFF
=
GND or in AutoShutdown
I
OUT
= 0.8mA
I
OUT
= -0.5mA
V
L
- 0.4 V
L
- 0.1
±10
0.4
µA
V
V
T_IN
FORCEON,
FORCEOFF
to V
L
T_IN, FORCEON,
FORCEOFF
T_IN, FORCEON,
FORCEOFF
0.66
✕
V
L
0.5
±0.01
±1
20
0.4
µA
V
V
V
µA
I
CC
FORCEON =
FORCEOFF
= V
L
no load
FORCEON or
FORCEOFF
= GND, V
CC
=
V
L
= +5v
FORCEON,
FORCEOFF
floating
0.3
85
1
1.65
V
CC
+ 0.3
10
10
1
1
V
µA
µA
mA
mA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
I
CC
I
L
µA
2
_______________________________________________________________________________________
+2.5V to +5.5V RS-232 Transceivers
in UCSP
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +2.5V to +5.5V, V
L
= +1.65V to +5.5V, C1–C4 = 0.1µF, tested at +3.3V ±10%, T
A
= T
MIN
to T
MAX
. Typical values are at T
A
=
+25°C, unless otherwise noted.) (Note 3)
PARAMETER
RECEIVER INPUTS
Input Voltage Range
Input Threshold Low
Input Threshold High
Input Hysteresis
Input Resistance
AUTOSHUTDOWN
Receiver Input Threshold to
INVALID
Output High
Receiver Input Threshold to
INVALID
Output Low
Receiver Positive or Negative
Threshold to
INVALID
High
Receiver Positive or Negative
Threshold to
INVALID
Low
Receiver Edge to Transmitters
Enabled
TRANSMITTER OUTPUTS
V
CC
Mode Switch Point
(V
CC
Falling)
V
CC
Mode Switch Point
(V
CC
Rising)
V
CC
Mode Switch Point Hysteresis
All transmitter
outputs loaded with
3kΩ to ground.
V
CC
= +3.1V to
+5.5V, V
CC
falling
V
CC
= +2.5V to
+2.9V
±5
±3.7
300
10M
±60
T_OUT = ±12V, transmitters disabled
I
OUT
= 0.8mA
I
OUT
= -0.5mA
V
CC
- 0.4 V
CC
- 0.1
±25
0.4
Ω
mA
µA
V
V
T_OUT = ±5.0V to ±3.7V
T_OUT = ±3.7V to ±5.0V
2.85
3.3
400
±5.4
V
3.1
3.7
V
V
mV
t
INVH
t
INVL
t
WU
V
CC
= +5.0V, Figure 3b
V
CC
= +5.0V, Figure 3b
V
CC
= +5.0V, Figure 3b
Figure 3a
Positive threshold
Negative threshold
-2.7
-0.3
1
30
100
0.3
2.7
V
V
µs
µs
µs
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
1.7
1.3
1.8
0.5
5
7
2.4
2.4
+25
V
V
V
V
kΩ
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX3228/MAX3229
Output Voltage Swing
Output Resistance
Output Short-Circuit Current
Output Leakage Current
INVALID
OUTPUT
Output Voltage Low
Output Voltage High
V
CC
= V+ = V- = 0, T_OUT = ±2V
_______________________________________________________________________________________
3
+2.5V to +5.5V RS-232 Transceivers
in UCSP
MAX3228/MAX3229
TIMING CHARACTERISTICS
(V
CC
= +2.5V to +5.5V, V
L
= +1.65V to +5.5V, C1–C4 = 0.1µF, tested at +3.3V ±10%, T
A
= T
MIN
to T
MAX
. Typical values are at T
A
=
+25°C, unless otherwise noted.) (Note 3)
PARAMETER
Maximum Data Rate
Receiver Propagation Delay
Receiver Output Enable-Time
Receiver Output Disable-Time
Transmitter Skew
Receiver Skew
Transition Region Slew Rate
| t
PHL
- t
PLH
|
| t
PHL
- t
PLH
|
R
L
= 3kΩ to 7kΩ, C
L
= 150pF to
1000pF, T
A
= +25°C
6
SYMBOL
CONDITIONS
R
L
= 3kΩ, C
L
= 1000pF, one transmitter
switching
Receiver input to receiver output,
C
L
= 150pF
V
CC
= V
L
= +5V
V
CC
= V
L
= +5V
MIN
250
0.15
200
200
100
50
30
TYP
MAX
UNITS
kbps
µs
ns
ns
ns
ns
V/µs
Note 3:
V
CC
must be greater than V
L
.
Typical Operating Characteristics
(V
CC
= +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ and C
L
, T
A
= +25°C, unless otherwise noted.)
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3228/9 toc01
SLEW RATE vs. LOAD CAPACITANCE
MAX3228/9 toc02
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE (MAX3229)
OPERATING SUPPLY CURRENT (mA)
18
16
14
12
10
8
6
4
2
0
20kbps
0
500
1000
1500
2000
2500
3000
250kbps
MAX3228/9 toc03
6
V
CC
RISING
TRANSMITTER OUTPUT VOLTAGE (V)
4
2
0
-2
-4
-6
0
500
1000
1500
2000
2500
V
OL
V
OH
30
25
SLEW RATE (V/µs)
20
15
10
5
0
V
CC
= 2.5V
V
CC
= 5.5V
20
3000
0
500
1000
1500
2000
2500
3000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
4
_______________________________________________________________________________________
+2.5V to +5.5V RS-232 Transceivers
in UCSP
MAX3228/MAX3229
Typical Operating Characteristics (continued)
(V
CC
= +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ and C
L
, T
A
= +25°C, unless otherwise noted.)
OPERATING SUPPLY CURRENT
vs. SUPPLY VOLTAGE (MAX3229)
MAX3228/9 toc04
TRANSMITTER OUTPUT VOLTAGE vs.
SUPPLY VOLTAGE (V
CC
RISING)
MAX3228/9 toc05
TRANSMITTER OUTPUT VOLTAGE vs.
SUPPLY VOLTAGE (V
CC
FALLING)
TRANSMITTER OUTPUT VOLTAGE (V)
8
6
4
2
0
-2
-4
-6
-8
V
OL
V
OH
MAX3228/9 toc06
20
OPERATING SUPPLY CURRENT (mA)
18
16
14
12
10
8
6
4
2
0
2.5
3.0
3.5
4.0
4.5
5.0
10
TRANSMITTER OUTPUT VOLTAGE (V)
8
6
4
2
0
-2
-4
-6
-8
V
OL
V
OH
10
5.5
2.5
3.0
3.5
4.0
4.5
5.0
5.5
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
Pin Description
PIN
MAX3228
A1
A2
A3
A4
A5
A6, B6
B1
B2, B3, B4,
C2, C3, C4,
D2, D3, D4,
D5
B5
—
C1
MAX3229
A1
A2
A3
A4
A5
A6
B1
B2, B3, B4,
C2, C3, C4,
D2, D3, D4,
D5
B5
B6, D6,
E4, E6
C1
NAME
V
CC
C2+
C2-
V-
V
L
T_IN
V+
+2.5V to +5.5V Supply Voltage
Positive Terminal of Inverting Charge-Pump Capacitor
Negative Terminal of Inverting Charge-Pump Capacitor
-5.5V/-4.0V Generated by Charge Pump
Logic-Level Input for Receiver Outputs and Transmitter Inputs. Connect V
L
to the
system logic supply voltage or V
CC
if no logic supply is required.
Transmitter Input(s)
+5.5V/+4.0V Generated by Charge Pump. If charge pump is generating +4.0V, the part
has switched from RS-232 compliant to RS-232 compatible mode.
FUNCTION
N.C.
No Connection. These locations are not populated with solder bumps.
FORCEON
N.C.
C1+
FORCEON Input, Active-High. Drive FORCEON high to override automatic circuitry,
keeping transmitters and charge pumps on. Pulls itself high internally if not connected.
No Connection. These locations are populated with solder bumps, but are electrically
isolated.
Positive Terminal of Positive Regulated Charge-Pump Capacitor
_______________________________________________________________________________________
5
