Rainbow Electronics MAX13223E User Manual

General Description
The MAX13223E is a +3.0V to +5.5V-powered EIA/TIA­232 and V.28 communications interface with fault protec­tion on the RS-232 line interface. This allows shorts of the transmitter outputs and receiver inputs to voltages in the ±70V range without adversely affecting the MAX13223E.
The MAX13223E achieves 1µA supply current using Maxim’s AutoShutdown™ feature. The MAX13223E automatically enters a low-power shutdown mode when the RS-232 cable is disconnected or the receivers are inactive. The device turns on again when a valid transi­tion at any receiver input is sensed. A proprietary, high­efficiency, dual charge-pump power supply and a low-dropout transmitter combine to deliver true RS-232 performance from a single +3.0V to +5.5V supply.
The MAX13223E has two receivers and two drivers and is guaranteed to run at data rates of 250kbps for one trans­mitter switching while maintaining RS-232 output levels.
The MAX13223E operates from input voltages ranging from +3.0V to +5.5V and is available in a 20-pin, 6.5mm x 4.4mm, TSSOP package. The MAX13223E is speci­fied over the -40°C to +85°C temperature range.
Applications
Automotive
Telematics Equipment
Base Stations
Utility Meters
Industrial Equipment
Telecomm Equipment
POS Terminal Equipment
Features
o ±70V Fault Protection
o +3.0V to +5.5V Supply Voltage
o Overvoltage Current Limiting
o Current Protection at Transmitter Outputs
o AutoShutdown
o 250kbps (Max) Data Rate
o Low Current Consumption in Shutdown 1µA (typ)
o Thermal Shutdown Protection
o ±8kV IEC 61000-4-2 Contact-Discharge Method
o -40°C to +85°C Operating Temperature Range
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V,
2Tx/2Rx RS-232 Transceiver
________________________________________________________________
Maxim Integrated Products
1
Ordering Information
19-4585; Rev 0; 4/09
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.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
AutoShutdown is a trademark of Maxim Integrated Products, Inc.
Typical Operating Circuit appears at end of data sheet.
Typical Operating Circuit
PART TEMP RANGE PIN-PACKAGE
MAX13223EEUP+ -40°C to +85°C 20 TSSOP
V
CC
C
BYPASS
0.1µF
V
C1
C2
TTL/CMOS
INPUTS
C1+
C1-
C2+
C2-
T1IN
T2IN
CC
MAX13223E
T1OUT
T2OUT
V+
V-
C3
C4
RS-232 OUTPUTS
TTL/CMOS
OUTPUTS
R1OUT
R2OUT
EN
FORCEON
GND
5k
5k
INVALID
FORCEOFF
R1IN
R2IN
RS-232 INPUTS
TO POWER­MANAGEMENT UNIT
V
CC
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC= +3.0V to +5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at V
CC
= +3.3V, TA= +25°C, unless otherwise
noted. For V
CC
= +3.0V to +3.6V, C1–C3 = 0.1µF, C4 = 1µF. For V
CC
= +4.5V to +5.5V, C1 = 47nF, C2–C3 = 330nF, C4 = 1µF.) (Note 2)
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.
(Voltages referenced to GND.) V
CC
...................................................................... -0.3V to +7.0V
V+ ..........................................................................-0.3V to +7.0V
V- ...........................................................................+0.3V to -7.0V
V+ to V- ................................................................................+13V
Input Voltages
T1IN, T2IN, EN, FORCEON, FORCEOFF ..........-0.3V to +6.0V
R1IN, R2IN .......................................................................±70V
Output Voltages
T1OUT, T2OUT ................................................................±70V
R1OUT, R2OUT, INVALID ......................-0.3V to (V
CC
+ 0.3V)
Short-Circuit Duration
T1OUT, T2OUT.......................................................Continuous
Continuous Power Dissipation (T
A
= +70°C)
20-Pin TSSOP (derate 13.6mW/°C above +70°C) .....1084mW
Junction-to-Case Thermal Resistance (θ
JC
) (Note 1)
20-Pin TSSOP...............................................................20°C/W
Junction-to-Ambient Thermal Resistance (θ
JA
) (Note 1)
20-Pin TSSOP............................................................73.8°C/W
Operating Temperature Range .......................... -40°C to +85°C
Junction Temperature..................................................... +150°C
Storage Temperature Range ............................ -65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-
layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial
.
Supply Voltage V
Supply Current
Supply Current AutoShutdown I
Supply Current Shutdown I
LOGIC INPUTS
Input-Logic Low V
Input-Logic High V
Transmitter Input Hysteresis V
Input Leakage Current I
RECEIVER OUTPUTS
Output Leakage Current I
Output-Voltage Low V
Output-Voltage High V
INVALID OUTPUT (AutoShutdown (FORCEON = GND, FORCEOFF = VCC))
Receiver-Input Level to INVALID Output High
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
CC
AutoShutdown disabled (FORCEON = FORCEOFF = V
ASD
SD
T_IN,LO
T_IN,HI
TX,INHYS
IN,LKG
RX , OU T,LK G
R X , OU T, L OIOUT
R X ,OU T , H I
V
RX_IN,
INV_HI
FORCEON = GND, FORCEOFF = VCC, R1IN and R2IN idle, T1IN and T2IN idle
FORCEOFF = GND 1.0 10 µA
T_IN, EN, FORCEON, FORCEOFF, V
= +3.3V to +3.6V, +5.0V to +5.5V
CC
T_IN, FORCEON, FORCEOFF, EN
T_IN, EN, FORCEON, FORCEOFF ±0.01 ±1 µA
EN = V
CC
= 1.6mA 0.4 V
I
= -1.0mA
OUT
Figure 6a
), no load
CC
VCC = +3.3V 2.0
V
= +5.0V 2.4
CC
Positive level 2.7
Negative level -2.7
3.0 5.5 V
815mA
1.0 10 µA
0.8 V
0.5 V
±0.05 ±10 µA
V
-
CC
0.6
VCC -
0.2
V
V
V
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V,
2Tx/2Rx RS-232 Transceiver
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VCC= +3.0V to +5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at V
CC
= +3.3V, TA= +25°C, unless otherwise
noted. For V
CC
= +3.0V to +3.6V, C1–C3 = 0.1µF, C4 = 1µF. For V
CC
= +4.5V to +5.5V, C1 = 47nF, C2–C3 = 330nF, C4 = 1µF.) (Note 2)
Receiver-Input Level to INVALID Output Low
INVALID Output-Voltage Low V
INVALID Output-Voltage High V
RECEIVER INPUTS
Input-Voltage Range V
Overvoltage Threshold | V
Input Threshold Low V
Input Threshold High V
Input Resistance R
TRANSMITTER OUTPUTS
Output-Voltage Swing V
Output Resistance R
Overvoltage Protection Threshold |V
Output Short-Circuit Current I
Overvoltage Current I
Output Leakage Current in Shutdown Mode
PROTECTION
Overvoltage Protection Range R1IN, R2IN, T1OUT, T2OUT -70 +70 V
ESD PROTECTION (Note 4)
R1IN, R2IN, T1OUT, T2OUT
All Other Pins Human Body Model ±2
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
V
RX_IN,
INV_LO
RX,INV_LOIOUT
RX,INV_HIIOUT
RX,IN
RX ,OV TH R
RX,LO
RX,HI
RX,INRES
TX,ROUTVCC
TX,FB
TX,SHORT
TX,IFBOUT
I
TX,LKG T_OUT = -12V, V
Figure 6a -0.3 +0.3 V
= 1.6mA 0.4 V
= -1.0mA
(Note 3) -70 +70 V
| 24 28.3 32 V
VCC = +3.3V 0.6
VCC = +5.0V 0.8
VCC = +3.3V 2.4
VCC = +5.0V 2.4
-24V < V
VCC = V+ = V- = 0 35 250
+32V < |V
RL = 3k, Figure 4 ±5 ±6 V
O
| 14 19 V
T_OUT = 0 ±80 mA
V
V
T_OUT = +12V 450 900
shutdown mode
IEC 6100-4-2 Contact Discharge ±8
Human Body Model ±8
R_IN
= V+ = V- = 0, T
> V
OUT
< -V
OUT
< +24V (Note 3) 3 5 7
| < +70V 35 250
R_IN
= ±2V 300
OUT
TX,FB
TX,FB
= 0 or 3V to 5.5V in
CC
V
-
CC
0.6
6
-6
-150 -80
V
V
V
k
mA
µA
kV
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver
4 _______________________________________________________________________________________
Note 2: All devices are 100% production tested at TA= +85°C. Specifications are over -40°C to +85°C and are guaranteed by design. Note 3: Both receivers will operate over the ±70V input range. The input resistance increases with input voltage. The input resistance
will increase within 24V |VR_IN| 32V.
Note 4: Guaranteed by design, not production tested. Note 5: Transmitter skew is measured at the transmitter zero crosspoints. Note 6: Output recovery time is the delayed time for the transmitter to enter normal operating mode after an overvoltage condition.
TIMING CHARACTERISTICS
(VCC= +3.0V to +5.5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VCC= +3.3V, TA= +25°C, unless otherwise noted. For V
CC
= +3.0V to +3.6V, C1–C3 = 0.1µF, C4 = 1µF. For VCC= +4.5V to +5.5V, C1 = 47nF, C2–C3 = 330nF, C4 = 1µF.) (Note 2)
Maximum Data Rate DR
Receiver Positive or Negative Threshold to INVALID High
Receiver Positive or Negative Threshold to INVALID Low
Receiver Edge to Transmitters Enabled
Receiver-Output Enable Time t
Receiver-Output Disable Time t
Receiver Skew |t
Transmitter Skew |t
Receiver Propagation Delay
Transmitter Propagation Delay
Transmitter Fall Time or Rise Time
Transmitter Time to Exit Shutdown
Output Recovery Time t
Transition-Region Slew Rate SR
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
R
= 3k, CL = 1000pF, one transmitter
PRHL
PTHL
t
INVH
t
INVL
t
WU
RX,EN
RX,DIS
- t
- t
t
PRHL
t
PRLH
t
PTHL
t
PTLH
, t
t
R
F
t
SHDN
TX,REC
OUT
L
switching, Figure 1
VCC = 5V, Figure 6b 1 µs
VCC = 5V, Figure 6b 30 µs
VCC = 5V, Figure 6b 135 µs
Normal operation 200 ns
Normal operation 200 ns
|50ns
PRLH
| (Note 5) 200 ns
PTLH
CL = 150pF, Figure 4
CL = 1nF, RL = 3k, Figure 3
Figure 3 0.3 µs
Figure 7 100 µs
CL = 1nF, RL = 5k (Note 6) 100 µs
VCC = 3.3V, RL = 3k to 7kΩ, TA = +25°C, measured from +3V to -3V or -3V to +3V, one transmitter switching, C
= 1nF
L
250 kbps
0.3
0.3
0.8
0.6
6 30 V/µs
µs
µs
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V,
2Tx/2Rx RS-232 Transceiver
_______________________________________________________________________________________ 5
Figure 3. Driver Propagation Delay
t
PRHL
t
PRLH
1.3V
1.7V
VCC/2
VCC/2
V
IL
V
0H
V
0L
R_IN
R_OUT
V
IH
tR, tF 10ns
Figure 4. Receiver Propagation Delay
Timing Diagrams
C
L
R
L
V
O
T_IN
T_OUT
Figure 1. Driver Test Circuit
T_IN
T_OUT
R_IN
15pF
Figure 2. Receiver Test Circuit
Test Circuits
V
CC
T_IN
0
V
0
T_OUT
-V
0
V
/2
CC
t
PTHL
3V
0
-3V
t
F
VCC/2
t
PTLH
-3V
3V
0
t
R
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver
6 _______________________________________________________________________________________
Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
-8
-6
-4
-2
0
2
4
6
8
0 1000 2000 3000 4000 5000
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX13223E toc01
LOAD CAPACITANCE (pF)
TRANSMITTER OUTPUT VOLTAGE (V)
V
OUT+
V
OUT-
0
22
20
18
16
14
12
10
8
6
4
2
0 5000
SLEW RATE
vs. LOAD CAPACITANCE
MAX13223E toc02
LOAD CAPACITANCE (pF)
SLEW RATE (V/µs)
20001000 3000 4000
+ SLEW
- SLEW
0
10
5
25
20
15
40
35
30
45
0 20001000 3000 4000 5000
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX13223E toc03
LOAD CAPACITANCE (pF)
SUPPLY CURRENT (mA)
250kbps
120kbps
20kbps
T1 TRANSMITTING AT 250kbps T2 TRANSMITTING AT 15.6kbps
TRANSMITTER TIME TO EXIT SHUTDOWN
5V/div
MAX13223E toc04
FORCEON = FORCEOFF
T2OUT
2V/div
VCC = +3.3V C1–C4 = 0.1µF
T1OUT
40µs/div
Detailed Description
Figure 2 shows the receiver test circuit. Figure 3 shows driver propagation delay and Figure 4 shows receiver propagation delay.
Dual Charge-Pump Voltage Converter
The MAX13223E internal power supply consists of a dual-mode regulated charge pump that provides output voltages of +5.5V (doubling charge pump) and -5.5V (inverting charge pump), regardless of the input volt­age (VCC) over the +3.0V to +5.5V range. 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. Each charge pump requires a fly­ing capacitor (C1, C2) and a reservoir capacitor (C3, C4) to generate the V+ and V- supplies.
RS-232 Transmitters
The transmitters are inverting level translators that con­vert logic levels to EIA/TIA-232/V.28 levels. They guar­antee a 250kbps data rate with worst-case loads of 3kin parallel with 1000pF, providing compatibility with PC-to-PC communication software. The MAX13223E can operate at data rates of 250kbps (max). Transmitters can be paralleled to drive multiple receivers. When FORCEOFF is driven to ground, or the AutoShutdown circuitry senses invalid voltage levels at all receiver inputs, the transmitters are disabled and the outputs are forced into a high-impedance state. Figure 5 shows a complete system connection.
RS-232 Receivers
The MAX13223E’s receivers convert RS-232 signals to logic output levels. Both receiver outputs can be tri­stated using the EN input. In shutdown (FORCEOFF = low) or in AutoShutdown, the MAX13223E’s receivers are active (Table 1). Driving EN high places the receivers’ outputs in a high-impedance state.
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V,
2Tx/2Rx RS-232 Transceiver
_______________________________________________________________________________________ 7
Pin Description
PIN NAME FUNCTION
1 EN
2 C1+ Positive Terminal of the Voltage Doubler Charge-Pump Capacitor
3 V+ +5.5V Generated by Charge Pump
4 C1- Negative Terminal of the Voltage Doubler Charge-Pump Capacitor
5 C2+ Positive Terminal of Inverting Charge-Pump Capacitor
6 C2- Negative Terminal of Inverting Charge-Pump Capacitor
7 V- -5.5V Generated by Charge Pump
8 T2OUT RS-232 Transmitter 2 Output
9 R2IN RS-232 Receiver 2 Input
10 R2OUT Receiver 2 Logic Output 11 INVALID Valid Signal Detector Output. INVALID is high if a valid RS-232 level is present on any receiver input.
12 T2IN Transmitter 2 Logic Input
13 T1IN Transmitter 1 Logic Input
14 FORCEON
15 R1OUT Receiver 1 Logic Output
16 R1IN RS-232 Receiver 1 Input
17 T1OUT RS-232 Transmitter 1 Output
18 GND Ground
19 V
20 FORCEOFF
CC
Receiver Enable Control Input. Drive EN low for normal operation. Drive EN high to force the receiver outputs (R1OUT, R2OUT) into a high-impedance state.
Active-High FORCEON Input. Drive FORCEON high to override AutoShutdown, keeping transmitters and charge pump on (FORCEOFF must be high).
+3.0V to +5.5V Supply Voltage. Bypass VCC with a 0.1µF ceramic capacitor located as close to the device as possible.
Active-Low FORCEOFF Input. Drive FORCEOFF low to shut down transmitters, receivers, and on-board charge pumps, overriding AutoShutdown and FORCEON.
MAX13223E
AutoShutdown
The MAX13223E achieves 1µA supply current with Maxim’s AutoShutdown feature, which operates when FORCEON is low and FORCEOFF is high. When the device senses no valid signal levels on both receiver inputs for > 30µs (typ), the onboard charge pump and drivers are shut off, reducing 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 either RS-232 receiver input. As a result, the system saves power. Table 2 summarizes the MAX13223E’s operating modes. FORCEON and FORCEOFF override
AutoShutdown. When neither control is asserted, the IC selects between these states automatically, based on receiver input levels. Figure 6a shows the input levels and Figure 6b shows the timing diagram for AutoShutdown operation.
Software-Controlled Shutdown
If direct software control is desired, INVALID can be used to indicate a DTR or Ring indicator signal. Connect FORCEOFF and FORCEON together to bypass AutoShutdown; therefore, the line acts as a SHDN input.
±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver
8 _______________________________________________________________________________________
Figure 5. Interface Under Control of PMU
Table 1. Receiver Control Truth Table
EN R_OUT
0 Active
1 High Impedence
Figures 6a and 6b. Trip Levels for Entering and Exiting AutoShutdown
POWER-
MANAGEMENT
UNIT OR CPU
FORCEOFF
FORCEON
INVALID
MAX13223E
UART
RS-232
a)
b)
RECEIVER
INPUT
VOLTAGE
INVALID OUTPUT
+2.7V
+0.3V
0
-0.3V
RECEIVER INPUT
-2.7V
+2.7V
+0.3V
-0.3V
(V)
-2.7V
V
CC
(V)
V+
V
CC
TRANSMITTER ENABLED, INVALID HIGH
INDETERMINATE
AutoShutdown, TRANSMITTER DISABLED,
1µA SUPPLY CURRENT
INDETERMINATE
TRANSMITTER ENABLED, INVALID HIGH
INVALID REGION
0
0
t
INVL
t
INVH
t
WU
V-
Applications Information
Capacitor Selection
The capacitor type used for C1–C4 is not critical for proper operation; either polarized or nonpolarized capacitors may be used. The charge pump requires
0.1µF capacitors for 3.3V operation. For other supply voltages, see Table 3 for required capacitor values. Do not use values smaller than those listed in Table 3. 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
In most circumstances, a 0.1µF VCCbypass capacitor is adequate. In applications that are sensitive to power-sup­ply noise, decouple VCCto ground with a capacitor of the same value as the charge-pump capacitor C1. Connect bypass capacitors as close to the IC as possible.
Transmitter Outputs when
Exiting Shutdown
Figure 7 shows two transmitter outputs when exiting shutdown mode. As they become active, the two trans­mitter outputs are shown going to opposite RS-232 lev­els. Each transmitter is loaded with 3kin parallel with 2500pF. The transmitter outputs display no ringing or undesirable transients as they come out of shutdown. Note that the transmitters are enabled only when the magnitude of V- exceeds approximately 3V.
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V,
2Tx/2Rx RS-232 Transceiver
_______________________________________________________________________________________ 9
Table 2. AutoShutdown Control
INPUTS OUTPUTS
FORCEOFF FORCEON
VALID RECEIVER INPUT
LEVEL
INVALID
OUTPUT
OPERATION MODE T_OUT
0 X No 0 Shutdown (Forced Off) High-Z
0 X Yes 1 Shutdown (Forced Off) High-Z
1 0 No 0
High-Z
1 0 Yes 1 Active (AutoShutdown) Active
1 1 No 0 Active (Forced On) Active
1 1 Yes 1 Active (Forced On) Active
Table 3. Required Capacitor Values
VCC (V)
C4 (µF)
3.0 to 3.6
0.1 0.1 1
4.5 to 5.5
0.047 0.33 1
X = Don’t Care.
40µs/div
5V/div
2V/div
T2OUT
T1OUT
VCC = +3.3V C1–C4 = 0.1µF
FORCEON = FORCEOFF
Figure 7. Transmitter Outputs when Exiting Shutdown or Powering Up
Shutdown (AutoShutdown)
C1, C
(µF) C2, C3 (µF)
BYPASS
MAX13223E
Fault Protection
The MAX13223E is designed to survive faults such as direct shorts to power supplies, miswiring faults, con­nector failures, and tool misapplications of the transmit­ter outputs and receiver inputs to voltages in the ±70V range without damage. This fault protection is applica­ble in all modes of the MAX13223E: active, shutdown, and powered down. Both receivers operate over the ±70V input range, but the termination resistor (R
RX,I
)
increases when |V
R_IN
| voltage exceeds ±32V. A receiver’s input termination resistor reduces to its nominal value if the input voltage reduces to within the ±24V range. The receiver inputs and transmitter out­puts are independently fault protected.
±8kV 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. In using the MAX13223E, C4 must be a 1µF capacitor for the extended ESD protection. The driver outputs and receiver inputs of the MAX13223E have extra protection against static electricity. Maxim’s engi­neers have developed state-of-the-art structures to pro­tect these pins against ESD of ±8kV 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) ±8kV using the Human Body Model
2) ±8kV using the Contact-Discharge Method speci-
fied in IEC 61000-4-2
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 8a shows the Human Body Model and Figure 8b 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
1.5kresistor.
IEC 61000-4-2
The IEC 61000-4-2 standard covers ESD testing and performance of finished equipment. It does not specifi­cally refer to integrated circuits. The major difference between tests done using the Human Body Model and IEC 61000-4-2 is higher peak current in IEC 61000-4-2, because series resistance is lower in the IEC 61000-4-2 model. Hence, the ESD withstand voltage measured to IEC 61000-4-2 is generally lower than that measured using the Human Body Model. Figure 9a shows the IEC 61000-4-2 model and Figure 9b shows the current waveform for the ±8kV, IEC 61000-4-2, level 4, ESD Contact-Discharge Method.
±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver
10 ______________________________________________________________________________________
Figure 8a. Human Body ESD Test Model
Figure 8b. Human Body Current Waveform
R
D
1500
DISCHARGE RESISTANCE
STORAGE CAPACITOR
HIGH-
VOLTAGE
DC
SOURCE
R
C
1M
CHARGE-CURRENT
LIMIT RESISTOR
C
100pF
s
IP 100%
90%
AMPERES
36.8%
10%
0
0
t
RL
TIME
t
DL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
I
r
(NOT DRAWN TO SCALE)
DEVICE UNDER
TEST
MAX13223E
±70V Fault-Protected, 3.0V to 5.5V,
2Tx/2Rx RS-232 Transceiver
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________
11
© 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
Figure 9a. IEC 61000-4-2 ESD Test Model
Figure 9b. IEC 61000-4-2 ESD Generator Current Waveform
Chip Information
PROCESS: CMOS
Pin Configuration
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
V
CC
GND
T1OUT
C1-
V+
C1+
R1IN
R1OUT
FORCEON
T1IN
T2OUT
V-
C2-
C2+
12
11
9
10
T2IN
R2OUT
R2IN
TSSOP
MAX13223E
INVALID
FORCEOFF
EN
TOP VIEW
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages
.
PACKAGE TYPE PACKAGE CODE DOCUMENT NO.
20 TSSOP U20+2
21-0066
R
D
330
DISCHARGE
RESISTANCE
STORAGE CAPACITOR
HIGH-
VOLTAGE
DC
SOURCE
R
C
50M to 100M
CHARGE CURRENT
LIMIT RESISTOR
C
150pF
s
I
100%
90%
PEAK
I
DEVICE UNDER
TEST
10%
tr = 0.7ns to 1ns
30ns
60ns
t
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