Maxim MAX3229AEEWV+T ±15kv esd-protected 2.5v to 5.5v rs-232 transceivers in ucsp and wlp Datasheet

19-2139; Rev 2; 10/08
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
The MAX3228E/AE and MAX3229E/AE are +2.5V to
+5.5V powered EIA/TIA-232 and V.28/V.24 communications interfaces with low power requirements, high datarate capabilities, and enhanced electrostatic discharge
(ESD) protection, in a chip-scale package (UCSP™)
and WLP Package. All transmitter outputs and receiver
inputs are protected to ±15kV using IEC 1000-4-2 AirGap Discharge, ±8kV using IEC 1000-4-2 Contact
Discharge, and ±15kV using the Human Body Model.
The MAX3228E/AE and MAX3229E/AE 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 transmitters of the connected peripherals are off.
The transceivers have a proprietary low-dropout transmitter output stage, delivering RS-232 compliant performance 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 supply. Each device is guaranteed to run at data rates of
250kbps while maintaining RS-232 output levels.
The MAX3228E/AE and MAX3229E/AE 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 VCC range, VL
provides the MAX3228E/AE and MAX3229E/AE compatibility with multiple logic families.
The MAX3229E/AE contains one receiver and one
transmitter. The MAX3228E/AE contains two receivers
and two transmitters. The MAX3228E/AE and
MAX3229E/AE are available in tiny chip-scale and WLP
packaging and are specified across the extended
industrial temperature range of -40°C to +85°C.
Applications
Personal Digital Assistants
Features
♦ 6 ✕ 5 Chip-Scale Package (UCSP) and WLP
Package
♦ ESD Protection for RS-232 I/O Pins:
±15kV—IEC 1000-4-2 Air-Gap Discharge
±8kV—IEC 1000-4-2 Contact Discharge
±15kV—Human Body Model
♦ 1µA Low-Power AutoShutdown
♦ 250kbps Guaranteed Data Rate
♦ Meets EIA/TIA-232 Specifications Down to +3.1V
♦ RS-232 Compatible to +2.5V Allows Operation
from Single Li+ Cell
♦ Small 0.1µF Capacitors
♦ Configurable Logic Levels
Ordering Information
TEMP RANGE
BUMP-PACKAGE
MAX3228EEBV-T
PART
-40°C to +85°C
6 x 5 UCSP*
MAX3228AEEWV+T
-40°C to +85°C
6 x 5 WLP
MAX3229EEBV-T
-40°C to +85°C
6 x 5 UCSP*
MAX3229AEEWV+T
-40°C to +85°C
6 x 5 WLP
+Denotes a lead-free/RoHS-compliant package.
*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.
T = Tape and reel.
Typical Operating Circuits
2.5V TO 5.5V 1.65V TO 5.5V
0.1μF
CBYPASS
0.1μF
A1
C1
C1
0.1μF
D1
A2
C2
0.1μF
A3
A5
VCC
C1+
C1-
VL
MAX3228E/AE
C2+
V-
T1OUT
TTL/CMOS
INPUTS
Typical Operating Circuits continued at end of data sheet.
C4
0.1μF
E3
RS-232
OUTPUTS
T2OUT E4
VL
Handheld Devices
Cell Phones
C3
0.1μF
A4
VL
B6 T2IN
Set-Top Boxes
B1
VL
C2-
A6 T1IN
Cell Phone Data Lump Cables
V+
R1IN
D6 R1OUT
TTL/CMOS
OUTPUTS
VL
E6
5kΩ
RS-232
INPUTS
R2IN E5
C6 R2OUT
5kΩ
Pin Configurations appear at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
AutoShutdown is a trademark of Maxim Integrated Products, Inc.
VL
VL
INVALID
20μA
20μA
E2
FORCEOFF C5
B5 FORCEON
TO POWERMANAGEMENT
UNIT
VL
GND
E1
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
General Description
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
ABSOLUTE MAXIMUM RATINGS
VCC 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
VL to GND..............................................................-0.3V to +6.0V
Input Voltages
T_IN_, FORCEON, FORCEOFF to GND .....-0.3V to (VL + 0.3V)
R_IN_ to GND ...................................................................±25V
Output Voltages
T_OUT to GND ...............................................................±13.2V
R_OUT INVALID to GND ............................-0.3V to (VL + 0.3V)
INVALID to GND..........................................-0.3V to (VCC +0.3V)
Short-Circuit Duration T_OUT to GND........................Continuous
Continuous Power Dissipation (TA = +70°C)
6 ✕ 5 UCSP (derate 10.1mW/°C above TA = +70°C) ...805mW
6 ✕ 5 WLP (derate 20mW/°C above TA = +70°C) ............1.6W
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 recommended in the industry-standard specification, JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and convection reflow. Preheating 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
(VCC = +2.5V to +5.5V, VL = +1.65V to +5.5V, C1–C4 = 0.1µF, tested at +3.3V ±10%, TA = TMIN to TMAX. Typical values are at TA =
+25°C, unless otherwise noted.) (Note 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC CHARACTERISTICS
VL Input Voltage Range
VCC Supply Current,
AutoShutdown
VCC Supply Current,
AutoShutdown Disabled
VL Supply Current
VL
ICC
ICC
IL
1.65
VCC + 0.3
V
FORCEON = GND
FORCEOFF = VL, all RIN open
10
µA
FORCEOFF = GND
10
µA
FORCEON, FORCEOFF floating
1
mA
1
mA
FORCEON = FORCEOFF = VL
no load
0.3
FORCEON or FORCEOFF = GND,
VCC = VL =+5V
85
FORCEON, FORCEOFF floating
1
µA
LOGIC INPUTS
Pullup Currents
FORCEON, FORCEOFF to VL
Input Logic Low
T_IN, FORCEON, FORCEOFF
Input Logic High
T_IN, FORCEON, FORCEOFF
Transmitter Input Hysteresis
Input Leakage Current
20
µA
0.4
0.66 ✕ VL
0.5
T_IN
V
V
±0.01
V
±1
µA
RECEIVER OUTPUTS
2
Output Leakage Currents
R_OUT, receivers disabled, FORCEOFF =
GND or in AutoShutdown
±10
µA
Output Voltage Low
IOUT = 0.8mA
0.4
V
Output Voltage High
IOUT = -0.5mA
VL - 0.4 VL - 0.1
_______________________________________________________________________________________
V
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
(VCC = +2.5V to +5.5V, VL = +1.65V to +5.5V, C1–C4 = 0.1µF, tested at +3.3V ±10%, TA = TMIN to TMAX. Typical values are at TA =
+25°C, unless otherwise noted.) (Note 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
+25
V
RECEIVER INPUTS
Input Voltage Range
-25
Input Threshold Low
TA = +25°C
Input Threshold High
TA = +25°C
VCC = +3.3V
0.6
1.2
VCC = +5.0V
0.8
1.7
V
VCC = +3.3V
1.3
2.4
VCC = +5.0V
1.8
2.4
Input Hysteresis
0.5
Input Resistance
3
5
V
V
7
kΩ
AUTO SHUTDOWN
Receiver Input Threshold to
INVALID Output High
Figure 3a
Positive threshold
Negative threshold
Receiver Input Threshold to
INVALID Output Low
2.7
-2.7
-0.3
0.3
V
V
Receiver Positive or Negative
Threshold to INVALID High
tINVH
VCC = +5.0V, Figure 3b
1
µs
Receiver Positive or Negative
Threshold to INVALID Low
tINVL
VCC = +5.0V, Figure 3b
30
µs
Receiver Edge to Transmitters
Enabled
tWU
VCC = +5.0V, Figure 3b
100
µs
INVALID OUTPUT
Output Voltage Low
IOUT = 0.3mA
Output Voltage High
IOUT = -0.5mA
0.4
VCC - 0.4
VCC - 0.1
V
V
TRANSMITTER OUTPUTS
VCC Mode Switch Point
(VCC Falling)
T_OUT = ±5.0V to ±3.7V
2.85
3.1
V
VCC Mode Switch Point
(VCC Rising)
T_OUT = ±3.7V to ±5.0V
3.3
3.7
V
VCC Mode Switch Point Hysteresis
Output Voltage Swing
Output Resistance
400
All transmitter
outputs loaded with
3kΩ to ground.
VCC = +3.1V to
+5.5V, VCC falling
(TA = +25°C)
±5
VCC = +2.5V to
+3.1V, VCC rising
±3.7
VCC = V+ = V- = 0, T_OUT = ±2V
±5.4
V
300
Ω
10M
Output Short-Circuit Current
Output Leakage Current
mV
T_OUT = ±12V, transmitters disabled
±60
mA
±25
µA
ESD PROTECTION
R_IN, T_OUT
Human Body Model
±15
IEC 1000-4-2 Air-Gap Discharge
±15
IEC 1000-4-2 Contact Discharge
±8
kV
_______________________________________________________________________________________
3
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
ELECTRICAL CHARACTERISTICS (continued)
TIMING CHARACTERISTICS
(VCC = +2.5V to +5.5V, VL = +1.65V to +5.5V, C1–C4 = 0.1µF, tested at +3.3V ±10%, TA = TMIN to TMAX. Typical values are at TA =
+25°C, unless otherwise noted.) (Note 3)
PARAMETER
CONDITIONS
MIN
Maximum Data Rate
RL = 3kΩ, CL = 1000pF, one transmitter
switching
250
Receiver Propagation Delay
Receiver input to receiver output,
CL = 150pF
0.15
μs
Receiver Output Enable-Time
VCC = VL = +5V
200
ns
SYMBOL
VCC = VL = +5V
Receiver Output Disable-Time
TYP
MAX
UNITS
kbps
200
ns
Transmitter Skew
| tPHL - tPLH |
100
ns
Receiver Skew
| tPHL - tPLH |
50
ns
RL = 3kΩ to 7kΩ, CL = 150pF to
1000pF, TA = +25°C
Transition Region Slew Rate
6
30
V/μs
Note 3: VCC must be greater than VL.
Typical Operating Characteristics
(VCC = +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.)
0
VOL
-2
10
5
-6
0
500
1000
1500
2000
LOAD CAPACITANCE (pF)
2500
3000
VCC = 5.5V
15
-4
0
4
20
VCC = 2.5V
MAX3228E/28AE/29E/29AE toc03
VOH
2
25
20
OPERATING SUPPLY CURRENT (mA)
4
30
MAX3228E/28AE/29E/29AE toc02
VCC RISING
SLEW RATE (V/µs)
6
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE (MAX3229E)
SLEW RATE vs. LOAD CAPACITANCE
MAX3228E/28AE/29E/29AE toc01
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
TRANSMITTER OUTPUT VOLTAGE (V)
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
18
16
14
250kbps
12
10
8
6
4
2
20kbps
0
0
500
1000
1500
2000
LOAD CAPACITANCE (pF)
2500
3000
0
500
1000
1500
2000
LOAD CAPACITANCE (pF)
_______________________________________________________________________________________
2500
3000
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
14
12
10
8
6
4
8
6
4
0
-2
-6
0
-8
3.0
3.5
4.0
4.5
5.0
5.5
VOL
-4
2
2.5
VOH
2
10
TRANSMITTER OUTPUT VOLTAGE (V)
16
10
MAX3228E/28AE/29E/29AE toc05
18
TRANSMITTER OUTPUT VOLTAGE (V)
MAX3228E/28AE/29E/29AE toc04
OPERATING SUPPLY CURRENT (mA)
20
TRANSMITTER OUTPUT VOLTAGE vs.
SUPPLY VOLTAGE (VCC FALLING)
TRANSMITTER OUTPUT VOLTAGE vs.
SUPPLY VOLTAGE (VCC RISING)
8
6
4
VOH
2
0
-2
VOL
-4
-6
-8
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)
MAX3228E/28AE/29E/29AE toc06
OPERATING SUPPLY CURRENT
vs. SUPPLY VOLTAGE (MAX3229E)
Pin Description
PIN
MAX3228E/ MAX3229E/
MAX3228AE MAX3229AE
NAME
FUNCTION
A1
A1
VCC
Supply Voltage. +2.5V to +5.5V supply voltage
A2
A2
C2+
Inverting Charge-Pump Capacitor Positive Terminal
A3
A3
C2-
Inverting Charge-Pump Capacitor Negative Terminal
A4
A4
V-
Negative Charge-Pump Output. -5.5V/-4.0V generated by charge pump.
A5
A5
VL
Logic Voltage Input. Logic-level input for receiver outputs and transmitter inputs.
Connect VL to the system logic supply voltage or VCC if no logic supply is required.
A6, B6
A6
T_IN
B1
B1
V+
Positive Charge-Pump Output. +5.5V/+4.0V generated by charge pump. If charge
pump is generating +4.0V, the device has switched from RS-232 compliant to RS-232
compatible mode.
B2, B3, B4,
C2, C3, C4,
D2, D3, D4,
D5
B2, B3, B4,
C2, C3, C4,
D2, D3, D4,
D5
N.C.
No Connection. The MAX3228AE/MAX3229AE are not populated with solder bumps at
these locations. The MAX3228AE/MAX3229AE are populated with electrically isolated
bumps at these locations.
B5
B5
FORCEON
Active-High FORCEON Input. Drive FORCEON high to override automatic circuitry,
keeping transmitters and charge pumps on. Pulls itself high internally if not connected.
—
B6, D6,
E4, E6
N.C.
No Connection. These locations are populated with solder bumps, but are electrically
isolated.
C1
C1
C1+
Positive Regulated Charge-Pump Capacitor Positive Terminal
Transmitter Input(s)
_______________________________________________________________________________________
5
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
Typical Operating Characteristics (continued)
(VCC = +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.)
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
Pin Description (continued)
PIN
MAX3228E/ MAX3229E/
MAX3228AE MAX3229AE
NAME
FUNCTION
Active-Low FORCEOFF Input. Drive FORCEOFF low to shut down transmitters,
receivers, and on-board charge pump. This overrides all automatic circuitry and
FORCEON. Pulls itself high internally if not connected.
C5
FORCEOFF
C6, D6
C6
R_OUT
D1
D1
C1-
Positive Regulated Charge-Pump Capacitor Negative Terminal
E1
E1
GND
Ground
E2
E2
INVALID
E3, E4
E3
T_OUT
E5, E6
E5
R_IN
C5
Receiver Output(s)
Valid Signal Detector Output. INVALID is enabled low if no valid RS-232 level is present
on any receiver input.
RS-232 Transmitter Output(s)
RS-232 Receiver Input(s)
Table 1. Operating Supply Options
SYSTEM SUPPLY (V)
VCC (V)
VL (V)
RS-232 MODE
1 Li+ Cell
+2.4 to +4.2
Regulated System Voltage
Compliant/Compatible
3 NiCad/NiMh Cells
+2.4 to +3.8
Regulated System Voltage
Compliant/Compatible
Regulated Voltage Only
(VCC falling)
+3.0 to +5.5
+3.0 to +5.5
Compliant
Regulated Voltage Only
(VCC falling)
+2.5 to +3.0
+2.5 to +3.0
Compatible
Detailed Description
Dual-Mode Regulated Charge-Pump
Voltage Converter
The MAX3228E/AE and MAX3229E/AE internal power
supply consists of a dual-mode regulated charge
pump. For supply voltages above +3.7V, the charge
pump will generate +5.5V at V+ and -5.5V at V-. 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.
For supply voltages below +2.85V, the charge pump
will generate +4.0V at V+ and -4.0V at V-. The charge
pumps operate in a discontinuous mode. If the output
voltages are less than ±4.0V, the charge pumps are
enabled, if the output voltages exceed ±4.0V, the
charge pumps are disabled.
The MAX3228E/AE and MAX3229E/AE include a
switchover circuit between these two modes that have
approximately 400mV of hysteresis around the
switchover point. The hysteresis is shown in Figure 1.
This large hysteresis eliminates mode changes due to
power-supply bounce.
For example, a three-cell NiMh battery system starts at
VCC = +3.6V, and the charge pump will generate an
output voltage of ±5.5V. As the battery discharges, the
VCC
4V
0
V+
6V
Each charge pump requires a flying capacitor (C1, C2)
and a reservoir capacitor (C3, C4) to generate the V+
and V- supply voltages.
Voltage Generation in the
Switchover Region
0
20ms/div
Figure 1. V+ Switchover for Changing VCC
6
_______________________________________________________________________________________
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
R_IN
-0.3V
30μs
COUNTER
R
TO MAX322 _E
POWER SUPPLY
AND TRANSMITTERS
R_IN
30μs
COUNTER
R
INVALID
*TRANSMITTERS ARE DISABLED, REDUCING SUPPLY CURRENT TO 1μA IF
ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR AT LEAST 30μs.
-2.7V
TO MAX322 _E
POWER SUPPLY
INVALID
*TRANSMITTERS ARE ENABLED IF:
ANY RECEIVER INPUT IS GREATER THAN +2.7V OR LESS THAN -2.7V.
ANY RECEIVER INPUT HAS BEEN BETWEEN +0.3V AND -0.3V FOR LESS THAN 30μs.
Figure 2a. MAX322_E Entering 1µA Supply Mode via
AutoShutdown
Figure 2b. MAX322_E with Transmitters Enabled Using
AutoShutdown
MAX3228E/AE and MAX3229E/AE maintain the outputs
in regulation until the battery voltage drops below +3.1V.
Then the output regulation points change to ±4.0V
When VCC is rising, the charge pump will generate an
output voltage of ±4.0V, while VCC is between +2.5V
and +3.5V. When VCC rises above the switchover voltage of +3.5V, the charge pump switches modes to
generate an output of ±5.5V.
Table 1 shows different supply schemes and their operating voltage ranges.
The transmitter inputs do not have pullup resistors.
Connect unused inputs to GND or VL.
RS-232 Transmitters
The transmitters are inverting level translators that convert CMOS-logic levels to RS-232 levels. The
MAX3228E/AE and MAX3229E/AE will automatically
reduce the RS-232 compliant levels (±5.5V) to RS-232
compatible levels (±4.0V) when V CC falls below
approximately +3.1V. The reduced levels also reduce
supply current requirements, extending battery life.
Built-in hysteresis of approximately 400mV for V CC
ensures that the RS-232 output levels do not change if
VCC is noisy or has a sudden current draw causing the
supply voltage to drop slightly. The outputs will return to
RS-232 compliant levels (±5.5V) when VCC rises above
approximately +3.5V.
The MAX3228E/AE and MAX3229E/AE transmitters
guarantee a 250kbps data rate with worst-case loads of
3kΩ in parallel with 1000pF.
When FORCEOFF is driven to ground, the transmitters
and receivers are disabled and the outputs become
high impedance. When the AutoShutdown circuitry
senses that all receiver and transmitter inputs are inactive for more than 30µs, the transmitters are disabled
and the outputs go to a high-impedance state. When
the power is off, the MAX3228E/AE and MAX3229E/AE
permit the transmitter outputs to be driven up to ±12V.
RS-232 Receivers
The MAX3228E/AE and MAX3229E/AE receivers convert RS-232 signals to logic output levels. All receivers
have inverting three-state outputs and can be active or
inactive. In shutdown (FORCEOFF = low) or in
AutoShutdown, the MAX3228E/AE and MAX3229E/AE
receivers are in a high-impedance state (Table 3).
The MAX3228E/AE and MAX3229E/AE feature an
INVALID output that is enabled low when no valid
RS-232 signal levels have been detected on any
receiver inputs. INVALID is functional in any mode
(Figures 2 and 3).
VL
FORCEOFF
POWER DOWN
VL
VCC
FORCEON
INVALID
INVALID IS AN INTERNALLY GENERATED SIGNAL
THAT IS USED BY THE AUTOSHUTDOWN LOGIC
AND APPEARS AS AN OUTPUT OF THE DEVICE.
POWER DOWN IS ONLY AN INTERNAL SIGNAL.
IT CONTROLS THE OPERATIONAL STATUS OF
THE TRANSMITTERS AND THE POWER SUPPLIES.
Figure 2c. MAX322_E AutoShutdown Logic
_______________________________________________________________________________________
7
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
+2.7V
+0.3V
AutoShutdown
The MAX3228E/AE and MAX3229E/AE achieve a 1µA
supply current with Maxim’s AutoShutdown feature,
which operates when FORCEON is low and FORCEOFF
is high. When these devices sense no valid signal levels on all receiver inputs for 30µs, the on-board charge
pump and drivers are shut off, reducing VCC supply
current to 1µA. This occurs if the RS-232 cable is disconnected or the connected peripheral transmitters are
turned off. The device turns on again when a valid level
is applied to any RS-232 receiver input. As a result, the
system saves power without changes to the existing
BIOS or operating system.
TRANSMITTERS ENABLED, INVALID HIGH
RECEIVER INPUT LEVELS
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
+2.7V
INDETERMINATE
+0.3V
0
AUTOSHUTDOWN, TRANSMITTERS DISABLED,
1μA SUPPLY CURRENT, INVALID LOW
-0.3V
INDETERMINATE
-2.7V
TRANSMITTERS ENABLED, INVALID HIGH
a)
RECEIVER
INPUT
VOLTAGE
(V)
INVALID
REGION
VCC
INVALID
OUTPUT
(V)
0
tINVL
tINVH
tWU
V+
VCC
0
V-
Table 3 and Figure 2c summarize the MAX3228E/AE
and MAX3229E/AE operating modes. FORCEON and
FORCEOFF override AutoShutdown. When neither control is asserted, the IC selects between these states
automatically, based on receiver input levels. Figures
2a, 2b, and 3a depict valid and invalid RS-232 receiver
levels. Figures 3a and 3b show the input levels and timing diagram for AutoShutdown operation.
A system with AutoShutdown may need time to wake
up. Figure 4 shows a circuit that forces the transmitters
on for 100ms, allowing enough time for the other
system to realize that the MAX3228E/AE and
MAX3229E/AE are active. If the other system transmits
valid RS-232 signals within that time, the RS-232 ports
on both systems remain enabled.
When shut down, the device’s charge pumps are off,
V+ is pulled to VCC, V- is pulled to ground, and the
transmitter outputs are high-impedance. The time
required to exit shutdown is typically 100µs (Figure 3b).
FORCEON and FORCEOFF
b)
Figure 3. AutoShutdown Trip Levels
POWERMANAGEMENT
UNIT
MASTER SHDN LINE
0.1μF
1MΩ
In case FORCEON and FORCEOFF are inaccessible,
these pins have 60kΩ (typ) pullup resistors connected to
VL (Table 2). Therefore, if FORCEON and FORCEOFF are
not connected, the MAX3228E/AE and MAX3229E/AE
will always be active. Pulling these pins to ground will
draw current from the VL supply. This current can be calculated from the voltage supplied at VL and the 60kΩ
(typ) pullup resistor.
FORCEOFF FORCEON
MAX3228E/AE
MAX3229E/AE
VL Logic Supply Input
Unlike other RS-232 interface devices, where the
receiver outputs swing between 0 and V CC , the
Table 2. Power-On Default States
Figure 4. AutoShutdown with Initial Turn-On to Wake Up a
Mouse or Another System
8
PIN NAME
POWER-ON DEFAULT
FORCEON
High
Internal pullup
FORCEOFF
High
Internal pullup
_______________________________________________________________________________________
MECHANISM
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
FORCEON
FORCEOFF
RECEIVER STATUS
Low
High
High-Z
L
X
Low
High-Z
†
Normal Operation (Forced On)
High
High
Active
†
Normal Operation (AutoShutdown)
Low
High
Active
H
TRANSCEIVER STATUS
Shutdown (AutoShutdown)
Shutdown (Forced Off)
INVALID
X = Don’t care.
† = INVALID output state is determined by R_IN input levels.
MAX3228E/AE and MAX3229E/AE feature a separate
logic supply input (VL) that sets VOH for the receiver
and INVALID outputs. The transmitter inputs (T_IN),
FORCEON and FORCEOFF, are also referred to VL.
This feature allows maximum flexibility in interfacing to
different systems and logic levels. Connect VL to the
system’s logic supply voltage (+1.65V to +5.5V), and
bypass it with a 0.1µF capacitor to GND. If the logic
supply is the same as VCC, connect VL to VCC. Always
enable VCC before enabling the VL supply. VCC must
be greater than or equal to the VL supply.
Software-Controlled Shutdown
If direct software control is desired, connect FORCEOFF and FORCEON together to disable AutoShutdown.
The microcontroller then drives FORCEOFF and
FORCEON like a SHDN input, INVALID can be used to
alert the microcontroller to indicate serial data activity.
RC 1MΩ
CHARGE-CURRENT
LIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
100pF
RD 1500Ω
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
Figure 5a. Human Body ESD Test Models
IP 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPERES
±15kV ESD Protection
As with all Maxim devices, ESD-protection structures are
incorporated on all pins to protect against electrostatic
discharges encountered during handling and assembly.
The driver outputs and receiver inputs of the
MAX3228E/AE and MAX3229E/AE have extra protection
against static electricity. Maxim’s engineers have developed state-of-the-art structures to protect these pins
against ESD of ±15kV without damage. The ESD structures withstand high ESD in all states: normal operation,
shutdown, and powered down. After an ESD event
Maxim’s E versions keep working without latchup,
whereas competing RS-232 products can latch and
must be powered down to remove latchup.
ESD protection can be tested in various ways; the transmitter outputs and receiver inputs of this product family
are characterized for protection to the following limits:
1) ±15kV using the Human Body Model.
2) ±8kV using the Contact Discharge method specified
in IEC 1000-4-2.
3) ±15kV using the IEC 1000-4-2 Air-Gap method.
36.8%
10%
0
0
tRL
TIME
tDL
CURRENT WAVEFORM
Figure 5b. Human Body Model Current Waveform
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents test
setup, test methodology, and test results.
Human Body Model
Figure 5a shows the Human Body Model, and Figure 5b
shows the current waveform it generates when discharged into a low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the test device through a
1.5kΩ resistor.
_______________________________________________________________________________________
9
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
Table 3. Output Control Truth Table
IEC 1000-4-2
The IEC 1000-4-2 standard covers ESD testing and performance of finished equipment; it does not specifically
refer to integrated circuits. The MAX3228E/AE and
MAX3229E/AE help you design equipment that meets
Level 4 (the highest level) of IED 1000-4-2, without the
need for additional ESD-protection components.
The major difference between tests done using the
Human Body Model and IEC 1000-4-2 is a higher peak
current in IEC 1000-4-2, because series resistance is
lower in the IEC 1000-4-2 model. Hence, the ESD withstand voltage measured to IEC 1000-4-2 is generally
lower than that measured using the Human Body Model.
Figure 6a shows the IEC 1000-4-2 model, and Figure 6b
shows the current waveform for the ±8kV IEC 1000-4-2
Level 4 ESD contact discharge test.
The air-gap test involves approaching the device with a
charged probe. The Contact Discharge method connects the probe to the device before the probe is energized.
RC 50MΩ to 100MΩ
CHARGE-CURRENT
LIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
150pF
RD 330Ω
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
Figure 6a. IEC 1000-4-2 ESD Test Model
Machine Model
The Machine Model for ESD tests all pins using a 200pF
storage capacitor and zero discharge resistance. Its
objective is to emulate the stress caused by contact that
occurs with handling and assembly during manufacturing. Of course, all pins require this protection during
manufacturing, not just RS-232 inputs and outputs.
Therefore, after PC board assembly, the Machine Model
is less relevant to I/O ports.
Applications Information
Capacitor Selection
The capacitor type used for C1–C4 is not critical for
proper operation; either polarized or non polarized
capacitors may be used. However, ceramic chip
capacitors with an X7R or X5R dielectric work best. The
charge pump requires 0.1µF capacitors for 3.3V operation. For other supply voltages, refer to Table 4 for
required capacitor values. Do not use values smaller
than those listed in Table 4. Increasing the capacitor
values (e.g., by a factor of 2) reduces ripple on the
transmitter outputs and slightly reduces power consumption. C2, C3, and C4 can be increased without
changing C1’s value. However, do not increase C1
without also increasing the values of C2, C3, and C4
to maintain the proper ratios (C1 to the other capacitors).
When using the minimum required capacitor values,
make sure the capacitor value does not degrade
excessively with temperature. If in doubt, use capacitors with a larger nominal value. The capacitor’s equivalent series resistance (ESR) usually rises at low
temperatures and influences the amount of ripple on V+
and V-.
Power-Supply Decoupling
I
100%
In most circumstances, a 0.1µF VCC bypass capacitor
is adequate. In applications that are sensitive to powersupply noise, use a capacitor of the same value as the
charge-pump capacitor C1. Connect bypass capacitors as close to the IC as possible.
90%
I PEAK
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
Table 4. Required Capacitor Values
10%
t r = 0.7ns to 1ns
t
30ns
60ns
VCC (V)
C1, CBYPASS (µF)
C2, C3, C4 (µF)
2.5 to 3.0
0.22
0.22
3.0 to 3.6
0.1
0.1
4.5 to 5.5
0.047
0.33
3.0 to 5.5
0.22
1
Figure 6b. IEC 1000-4-2 ESD Generator Current Waveform
10
______________________________________________________________________________________
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
Figure 7 shows a transmitter output when exiting shutdown mode. The transmitter is loaded with 3kΩ in parallel with 1000pF. The transmitter output displays no
ringing or undesirable transients as it comes out of
shutdown, and is enabled only when the magnitude of
V- exceeds approximately -3V.
For Figure 9, the transmitter was driven at 120kbps into
an RS-232 load in parallel with 1000pF. For Figure 10, a
single transmitter was driven at 250kbps, and loaded
with an RS-232 receiver in parallel with 1000pF.
High Data Rates
The MAX3228E/AE and MAX3229E/AE maintain the RS232 ±5.0V minimum transmitter output voltage even at
high data rates. Figure 8 shows a transmitter loopback
test circuit. Figure 9 shows a loopback test result at
120kbps, and Figure 10 shows the same test at 250kbps.
5V
5V/div
FORCEON =
FORCEOFF
T_IN
0
0
5V
0
T_OUT
-5V
5V
2V/div
TOUT
R_OUT
0
4μs/div
4μs/div
Figure 7. Transmitter Outputs Exiting Shutdown or Powering Up
VCC
0
Figure 9. Loopback Test Result at 120kbps
VL
5V
0.1μF
0.1μF
T_IN
C1+
VCC
VL
0
V+
5V
C3
C1
C1-
T_OUT
MAX3229E/AE
C2+
0
V-
C2
-5V
C4
C2-
VL
5V
T1OUT
T1IN
R_OUT
4μs/div
R1IN
R1OUT
Figure 10. Loopback Test Result at 250kbps
5kΩ
INVALID
FORCEON
GND
0
1000pF
VL
FORCEOFF
TO POWERMANAGEMENT UNIT
VL
Figure 8. Transmitter Loopback Test Circuit
______________________________________________________________________________________
11
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
Transmitter Outputs when
Exiting Shutdown
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
Typical Operating Circuits
(continued)
2.5V TO 5.5V 1.65V TO 5.5V
CBYPASS
0.1μF
A1
C1
C1
0.1μF
D1
A2
C2
0.1μF
A3
VCC
C1+
C1-
0.1μF
A5
VL
V+
MAX3229E/AE
C2+
V-
B1
C3
0.1μF
A4
C4
0.1μF
VL
C2-
T1OUT
A6 T1IN
E3
VL
TTL/CMOS
RS-232
R1IN E5
C6 R1OUT
5kΩ
VL
VL
INVALID
20μA
E2
20μA
FORCEOFF C5
B5 FORCEON
TO POWERMANAGEMENT
UNIT
UCSP Reliability
The UCSP represents a unique packaging form factor
that may not perform equally to a packaged product
through traditional mechanical reliability tests. CSP reliability is integrally linked to the user’s assembly methods,
circuit board material, and usage environment. The user
should closely review these areas when considering use
of a CSP package. Performance through Operating Life
Test and Moisture Resistance remains uncompromised
as it is primarily determined by the wafer-fabrication
process.
Mechanical stress performance is a greater consideration for a CSP package. CSPs are attached through
direct solder contact to the user’s PC board, foregoing
the inherent stress relief of a packaged product lead
frame. Solder joint contact integrity must be considered.
Table 2 shows the testing done to characterize the CSP
reliability performance. In conclusion, the UCSP is capable of performing reliably through environmental stresses
as indicated by the results in the table. Additional usage
data and recommendations are detailed in the UCSP
application note, which can be found on Maxim’s website at www.maxim-ic.com.
Chip Information
VL
TRANSISTOR COUNT: 698
PROCESS TECHNOLOGY: CMOS
GND
E1
Table 2. Reliability Test Data
TEST
Temperature Cycle
CONDITIONS
-35°C to +85°C,
-40°C to +100°C
DURATION
NO. OF FAILURES PER
SAMPLE SIZE
150 cycles,
900 cycles
0/10,
0/200
Operating Life
TA = +70°C
240hr
0/10
Moisture Resistance
+20°C to +60°C, 90% RH
240hr
0/10
Low-Temperature Storage
Low-Temperature
Operational
Solderability
-20°C
240hr
0/10
-10°C
24hr
0/10
8hr steam age
—
0/15
ESD
±2000V, Human Body Model
—
0/5
High-Temperature Operating
Life
TJ = +150°C
168hr
0/45
12
______________________________________________________________________________________
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
TOP VIEW
A
VCC
C2+
C2-
V-
VL
T1IN
B
V+
N.C.
N.C.
N.C.
FON
T2IN
C
C1+
N.C.
N.C.
N.C.
FOFF
R2OUT
D
C1-
N.C.
N.C.
N.C.
N.C.
R1OUT
E
GND
INV
T1OUT
T2OUT
R2IN
R1IN
1
2
3
4
5
MAX3228E/AE
6
FON = FORCEON
FOFF = FORCEOFF
INV = INVALID
______________________________________________________________________________________
13
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
Pin Configurations
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
Pin Configurations (continued)
TOP VIEW
A
VCC
C2+
C2-
V-
VL
T1IN
B
V+
N.C.
N.C.
N.C.
FON
N.C.
C
C1+
N.C.
N.C.
N.C.
FOFF
R1OUT
D
C1-
N.C.
N.C.
N.C.
N.C.
N.C.
E
GND
INV
T1OUT
N.C.
R1IN
N.C.
1
2
3
4
5
MAX3229E/AE
14
6
FON = FORCEON
FOFF = FORCEOFF
INV = INVALID
______________________________________________________________________________________
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
PACKAGE TYPE
PACKAGE CODE
DOCUMENT NO.
6 x 5 UCSP
B30-2
21-0123
6 x 5 WLP
W302A3-2
21-0016
______________________________________________________________________________________
15
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
MAX3228E/MAX3228AE/MAX3229E/MAX3229AE
±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
Revision History
REVISION
NUMBER
REVISION
DATE
0
8/01
Initial release
1
5/04
Changed output voltage swing spec
3
2
10/08
Addition of lead-free WLP packaging
1, 5, 6, 7, 15
DESCRIPTION
PAGES CHANGED
—
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2008 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
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