STMICROELECTRONICS ST3237EC

ST3237E
±15KV ESD-PROTECTED, 1µA, 3 TO 5.5V, 250KBPS,
RS-232 TRANSCEIVER WITH STAND-BY
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EDS PROTECTION FOR RS-232 I/O PINS:
±15KV HUMAN BODY MODEL
±8KV IEC 1000-4-2 CONTACT DISCHARGE
1µA LOW POWER SHUTDOWN WITH
RECEIVERS ACTIVE
GUARENTEED DATA RATE
250Kbps (Normal Operation)
1Mbps (Very High Speed Operation)
GUARANTEED SLEW RATE RANGE
6V/µs (Normal Operation)
24V/µs (Very High Speed Operation)
0.1µF EXTERNAL CAPACITORS
FLOW-THROUGH PINOUT
AVAILABLE IN SO-28, SSOP-28 AND
TSSOP28
LOW SUPPLY CURRENT 300µA
SOP
SSOP
DESCRIPTION
The ST3237E is a 3V to 5.5V powered EIA/
TIA-232 and V.28/V.24 communication interfaces
high data-rate capability and enhanced
electrostatic discharge (ESD) protection at ±8KV
using IEC1000-4-2 contact discharge and ±15kV
using Human Body Model (HBM). The other pins
are protected with standard ESD protection at
±2kV using HBM method. The ST3237C is a
transceiver (5 drivers, 3 receivers) for fast modem
applications.
The device has a proprietary low-dropout
transmitter output stage providing true RS-232
TSSOP
performance from a 3V to 5.5V supply using a
dual charge pump. The device is guaranteed to
run at data rates of 250Kbps in the normal
operation mode and 1Mbps in the very high speed
operation mode while maintaining RS-232 output
levels.
ORDERING CODES
Type
Temperature
Range
Package
Comments
ST3237ECD
ST3237EBD
ST3237ECDR
ST3237EBDR
ST3237ECPR
ST3237EBPR
ST3237ECTR (*)
ST3237EBTR
0 to 70 °C
-40 to 85 °C
0 to 70 °C
-40 to 85 °C
0 to 70 °C
-40 to 85 °C
0 to 70 °C
-40 to 85 °C
SO-28 (Tube)
SO-28 (Tube)
SO-28 (Tape & Reel)
SO-28 (Tape & Reel)
SSOP-28 (Tape & Reel)
SSOP-28 (Tape & Reel)
TSSOP28 (Tape & Reel)
TSSOP28 (Tape & Reel)
27parts per tube / 12tube per box
27parts per tube / 12tube per box
1000 parts per reel
1000 parts per reel
1350 parts per reel
1350 parts per reel
2500 parts per reel
2500 parts per reel
January 2003
1/13
ST3237E
PIN DESCRIPTION
PlN N°
NAME AND FUNCTION
1
C2+
Positive Terminal of Inverting Charge Pump Capacitor
2
GND
C2-
Ground
Negative Terminal of Inverting Charge Pump Capacitor
3
4
5
VT1OUT
-5.5V Generated by the Charge Pump
First Transmitter Output Voltage
6
T2OUT
Second Transmitter Output Voltage
7
T3OUT
Third Transmitter Output Voltage
8
R1IN
First Receiver Input Voltage
9
R2IN
Second Receiver Input Voltage
10
T4OUT
11
R3IN
12
T5OUT
Fifth Transmitter Output Voltage
13
14
15
EN
SHDN
VHSCI
16
R1OUTB
Receiver Enable, Active Low
Shutdown Control, Active Low
Very High Speed Control Input. Connected to GND for normal
operation; connected to VCC for 1Mbps transmission rates.
Non Inverting Complementary Receiver Output. Always Active.
Fourth Transmitter Output Voltage
Third Receiver Input Voltage
17
T5IN
Fifth Transmitter Input Voltage
18
R3OUT
Third Receiver Output Voltage
19
T4IN
Fourth Transmitter Input Voltage
20
R2OUT
Second Receiver Output Voltage
21
R1OUT
First Receiver Output Voltage
22
T3IN
Third Transmitter Input Voltage
23
T2IN
Second Transmitter Input Voltage
24
T1N
First Transmitter Input Voltage
25
C1-
Negative Terminal of Voltage-Doubler Charge Pump Capacitor
26
VCC
Supply Voltage
27
V+
C1 +
5.5V Generated by the Charge Pump
Positive Terminal of Voltage-Doubler Charge Pump Capacitor
28
2/13
SYMBOL
ST3237E
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
Symbol
VCC
V+
VV+ +|V-|
TIN
Parameter
Value
Unit
Supply Voltage
-0.3 to 6
V
Doubled Voltage Terminal
Inverted Voltage Terminal
-0.3 to 7
0.3 to -7
13
V
V
V
Transmitter Input Voltage Range
-0.3 to 6
V
-0.3 to 6
-0.3 to (VCC +0.3)
V
SHDN, EN
VHSCI
Very High Speed Control Input
RIN
Receiver Input Voltage Range
± 25
V
± 13.2
V
-0.3 to (VCC + 0.3)
V
Transmitter Output Voltage Range
TOUT
ROUT, ROUTB Receiver Output Voltage Range
tSHORT
Tstg
V
Short Circuit Duration on TOUT (one at a time)
Continuous
Storage Temperature Range
-65 to 150
°C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is
not implied. V+ and V- can have a maximum magnitude of +7V, but their absolute addition can not exceed 13 V.
SHUTDOWN AND ENABLE CONTROL TRUTH TABLE
SHDN
EN
T-OUT
R-OUT
R-OUTB
0
0
1
1
0
1
0
1
High Z
High Z
Active
Active
Active
High Z
Active
High Z
Active
Active
Active
Active
3/13
ST3237E
ESD PERFORMANCE: TRANSMITTER OUTPUTS, RECEIVER INPUTS
Symbol
ESD
ESD
Parameter
ESD Protection Voltage
ESD Protection Voltage
Test Conditions
Human Body Model
IEC-1000-4-2 Contact Discharge
Min.
Typ.
Max.
±15
±8
Unit
kV
kV
ELECTRICAL CHARACTERISTICS
(C1 - C4 = 0.1µF, VCC = 3V to 5.5V, TA = -40 to 85°C, unless otherwise specified.
Typical values are referred to TA = 25°C)
Symbol
Parameter
ISUPPLY VCC Power Supply Current
ISHDN
Shutdown Supply Current
Test Conditions
SHDN=VCC
Min.
No Load
SHDN=GND VT_IN=GND or VCC
Typ.
Max.
Unit
0.3
1
mA
1
5
µA
Typ.
Max.
Unit
0.8
V
LOGIC INPUT ELECTRICAL CHARACTERISTICS
(C1 - C4 = 0.1µF, VCC = 3V to 5.5V, TA = -40 to 85°C, unless otherwise specified.
Typical values are referred to TA = 25°C)
Symbol
Parameter
VTIL
Input Logic Threshold Low
(Note 1)
Input Logic Threshold High
T-IN, VHSCI, EN, SHDN
Input Leakage Current
T-IN, VHSCI, EN, SHDN
VTIH
Test Conditions
T-IN, VHSCI, EN, SHDN
VCC = 3.3V
VCC = 5V
IIL
VHYS
Min.
2
V
2.4
± 1.0
Transmitter Input
Hysteresis
0.25
µA
V
Note 1: Transmitter input hysteresis is typically 250mV
TRANSMITTER ELECTRICAL CHARACTERISTICS
(C1 - C4 = 0.1µF tested at 3.3V±10%, VCC = 3V to 5.5V, TA = -40 to 85°C, unless otherwise specified.
Typical values are referred to TA = 25°C)
Symbol
Parameter
VTOUT
Output Voltage Swing
RTOUT
ISC
Transmitter Output
Resistance
Output Short Circuit Current
ITOL
Output Leakage Current
4/13
Test Conditions
All Transmitter outputs are loaded with
3KΩ to GND
VCC = 0V
VOUT = ± 2V
VCC = 0V or 3.3V to 5.5V VOUT = ± 12V
Transmitters Disable
Min.
Typ.
Max.
±5
± 5.4
V
300
10M
Ω
± 60
mA
± 25
Unit
µA
ST3237E
RECEIVER ELECTRICAL CHARACTERISTICS
(C1 - C4 = 0.1µF tested at 3.3V±10%, VCC = 3V to 5.5V, TA = -40 to 85°C, unless otherwise specified.
Typical values are referred to TA = 25°C)
Symbol
Parameter
Test Conditions
IOL
Output Leakage Current
Receiver Disabled
VOL
Output Voltage Low
IOUT = 1mA
VOH
Output Voltage High
IOUT = -1mA
VRIN
Receiver Input Voltage
Operating Range
RS-232 Input Threshold
Low
VRIL
VRIH
RS-232 Input Threshold
High
Min.
EN=VCC
Input Resistance
Max.
Unit
± 0.05
± 10
µA
0.4
V
VCC-0. VCC-0.1
6
-25
V
25
TA = 25°C
VCC = 3.3V
0.6
1.1
TA = 25°C
VCC = 5V
0.8
1.5
TA = 25°C
VCC = 3.3V
1.5
2.4
TA = 25°C
VCC = 5V
1.2
2.4
VRIHYS Input Hysteresis
RRIN
Typ.
V
0.3
TA = 25°C
3
5
V
V
V
7
KΩ
TIMING CHARACTERISTICS
(C1 - C4 = 0.1µF tested at 3.3V±10%, VCC = 3V to 5.5V, TA = -40 to 85°C, unless otherwise specified.
Typical values are referred to TA = 25°C)
Symbol
DR
Parameter
Maximum Data Rate
Test Conditions
RL = 3KΩ
CL= 1000pF
one transmitter switching VHSCI=GND
CL= 250pF
RL = 3KΩ
one transmitter switching VHSCI=VCC
VCC= 3 to 4.5V
CL= 1000pF
RL = 3KΩ
one transmitter switching VHSCI=VCC
VCC= 4.5 to 5.5V
tPHLR
tPLHR
Propagation Delay Input to
Output
RIN to ROUT
CL = 150pF
tPHLR
tPLHR
Propagation Delay Input to
Output
RL = 3kΩ
VHSCI=VCC
VHSCI=GND
|tPHL - tTLH|
CL = 1000pF
|tPHL - tTLH|
VHSCI=VCC
tT_SKEW Transmitter Skew
tR_SKEW Receiver Skew
tOER
tODR
SRT
Receiver Output Enable
Time
Receiver Output Disable
Time
Transition Slew Rate
Min.
Typ.
Max.
Unit
250
Kbps
1000
Kbps
1000
Kbps
VHSCI=GND
0.15
µs
400
1000
ns
ns
300
ns
50
ns
|tPHL - tTLH|
100
ns
Normal Operation
50
ns
Normal Operation
120
ns
TA = 25°C RL = 3 to 7KΩ
VCC = 3.3V
measured from +3V to -3V or -3V to +3V
CL = 150pF to 1000pF VHSCI=GND
CL = 150pF to 1000pF VHSCI=VCC
CL = 150pF to 2500pF VHSCI=GND
6
24
4
30
150
30
V/µs
V/µs
V/µs
Transmitter Skew is measured at the transmitter zero cross points
5/13
ST3237E
APPLICATION CIRCUITS
CAPACITANCE VALUE (µF)
VCC
3.0 to
3.1 to
4.5 to
3.0 to
6/13
3.6
3.6
5.5
5.5
C1
C2
C3
C4
Cbypass
0.22
0.1
0.047
0.22
0.22
0.1
0.33
0.1
0.22
0.1
0.33
0.1
0.22
0.1
0.33
0.1
0.1
0.1
0.1
0.1
ST3237E
TYPICAL PERFORMANCE CHARACTERISTICS (unless otherwise specified Tj = 25°C)
Figure 1 : LOW Level Receiver Output Current
Figure 2 : HIGH Level Receiver Output Current
ESD PROTECTION
Note: The High ESD protected pins are the I/O RS232 line, transmitter out and receiver in. The other pins guarantee ± 2KV HBM ESD protection versus ground by means of diodes.
7/13
ST3237E
APPLICATION NOTE
This application note describes the procedure for determining the susceptibility and the test method to
verify ST ESD advanced protection on RS-232 or RS485 I/O device.
Static electricity is defined as an electrical charge caused by an imbalance of electrons on the surface of
a material. This imbalance of electrons produces an electric field that can be measured and that can
influence other objects at a distance. Electrostatic discharge is defined as the transfer of charge between
bodies at different electrical potentials. Electrostatic discharge (ESD) can change the electrical
characteristics of a semiconductor device, degrading or destroying it. Any input or output port (I/O) allows
access communication with other pieces of equipment by external connectors. These connectors are
directly linked by the I/O pins of RS-232 or RS485 interface. ST provides the E-series by advanced high
ESD protection structure. The protection functionality is tested in two different conditions:
The first model is used to simulate the HUMAN BODY MODEL (HBM) event. A similar discharge can
occur from a charged conductive object, such as a metallic tool or fixture. The model used to characterize
this event is known as the Machine Model. A Human Body Model circuit and waveform is presented in
Figures below.
HUMAN BODY MODEL CIRCUIT
HUMAN BODY MODEL CURRENT WAVEFORM
The second model is IEC 1000-4-2 and is used to simulate the reaction of the device on equipment when
subjected to electrostatic discharges, which may occur from personnel to objects near vital
instrumentation. Direct (Contact) and indirect (Air Gap) applications of discharges to the equipment under
test (EUT) are possible. Test characteristics are shown in circuit, waveform and table below.
8/13
ST3237E
IEC 1000-4-2 CIRCUIT
IEC 1000-4-2 CURRENT WAVEFORM
CHARACTERISTICS OF THE ESD GENERATOR
Level
1
2
3
4
Indicated
Voltage
2
4
6
8
KV
KV
KV
KV
First Peak Current of Rise Time With Discharge Current at 30 ns Current at 60 ns
Discharge (± 10%)
(± 30%)
(± 30%)
Switch
7.5 A
15 A
22.5 A
30 A
0.7 to
0.7 to
0.7 to
0.7 to
1ns
1ns
1ns
1ns
4A
8A
12 A
16 A
2A
4A
6A
8A
9/13
ST3237E
SO-28 MECHANICAL DATA
mm.
inch
DIM.
MIN.
TYP
A
MAX.
MIN.
TYP.
2.65
MAX.
0.104
a1
0.1
0.3
0.004
0.012
b
0.35
0.49
0.014
0.019
b1
0.23
0.32
0.009
0.012
C
0.5
0.020
c1
45˚ (typ.)
D
17.70
18.10
0.697
0.713
E
10.00
10.65
0.393
0.419
e
1.27
0.050
e3
16.51
0.650
F
7.40
7.60
0.291
0.300
L
0.50
1.27
0.020
0.050
S
8 ˚ (max.)
0016023
10/13
ST3237E
SSOP28 MECHANICAL DATA
mm.
inch
DIM.
MIN.
TYP
A
MAX.
MIN.
TYP.
2
A1
0.050
A2
1.65
b
MAX.
0.079
0.002
1.85
0.065
0.22
0.38
0.009
0.015
c
0.09
0.25
0.004
0.010
D
9.9
10.2
10.5
0.390
0.402
0.413
E
7.4
7.8
8.2
0.291
0.307
0.323
E1
5
5.3
5.6
0.197
0.209
0.220
e
1.75
0.65 BSC
K
0˚
L
0.55
0.75
0.069
0.073
0.0256 BSC
10˚
0˚
0.95
0.022
10˚
0.030
0.037
11/13
ST3237E
TSSOP28 MECHANICAL DATA
mm.
inch
DIM.
MIN.
TYP
A
MAX.
MIN.
TYP.
MAX.
1.2
A1
0.05
A2
0.8
b
0.047
0.15
0.002
0.004
0.006
1.05
0.031
0.039
0.041
0.19
0.30
0.007
0.012
c
0.09
0.20
0.004
0.0079
D
9.6
9.7
9.8
0.378
0.382
0.386
E
6.2
6.4
6.6
0.244
0.252
0.260
E1
4.3
4.4
4.48
0.169
0.173
0.176
e
1
0.65 BSC
K
0˚
L
0.45
0.60
0.0256 BSC
8˚
0˚
0.75
0.018
8˚
0.024
0.030
0128292B
12/13
ST3237E
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from
its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications
mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information
previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or
systems without express written approval of STMicroelectronics.
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© 2003 STMicroelectronics - Printed in Italy - All Rights Reserved
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13/13