STMICROELECTRONICS ST3237ECPR

ST3237E
±15KV ESD-PROTECTED, 1µA, 3 TO 5.5V, 250KBPS,
RS-232 TRANSCEIVER WITH STAND-BY
■
■
■
■
■
■
■
■
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 AND SSOP-28
LOW SUPPLY CURRENT 300µA
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
SSOP
SOP
±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
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.
Table 1: Order Codes
Type
Temperature
Range
Package
Comments
ST3237ECD
ST3237EBD
ST3237ECDR
ST3237EBDR
ST3237ECPR
ST3237EBPR
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)
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
March 2005
Rev. 5
1/15
ST3237E
Table 2: Pin Description
PlN N°
SYMBOL
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
2/15
NAME AND FUNCTION
ST3237E
Figure 1: Pin Configuration
Table 3: Absolute Maximum Ratings
Symbol
VCC
V+
VV+ +|V-|
TIN
Parameter
Value
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
ROUT, ROUTB Receiver Output Voltage Range
± 25
V
V
-0.3 to (VCC + 0.3)
V
Short Circuit Duration on TOUT (one at a time)
Storage Temperature Range
tSHORT
Tstg
V
± 13.2
Transmitter Output Voltage Range
TOUT
Unit
Continuous
-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.
Table 4: 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
Table 5: 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.
±15
±8
Typ.
Max.
Unit
kV
kV
3/15
ST3237E
Table 6: 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=GNDVT_IN=GND or VCC
Typ.
Max.
Unit
0.3
1
mA
1
5
µA
Typ.
Max.
Unit
0.8
V
Table 7: 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
VTIH
Test Conditions
Min.
T-IN, VHSCI, EN, SHDN
T-IN, VHSCI, EN, SHDN
VCC = 3.3V
VCC = 5V
IIL
VHYS
Input Leakage Current
2
V
2.4
± 1.0
T-IN, VHSCI, EN, SHDN
Transmitter Input
Hysteresis
0.25
µA
V
Note 1: Transmitter input hysteresis is typically 250mV
Table 8: 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
VTOUT
RTOUT
Parameter
Test Conditions
Output Voltage Swing
All Transmitter outputs are loaded with
3KΩ to GND
Transmitter Output Resistance VCC = 0V
VOUT = ± 2V
ISC
Output Short Circuit Current
ITOL
Output Leakage Current
Min.
Typ.
Max.
±5
± 5.4
V
300
10M
Ω
± 60
VCC = 0V or 3.3V to 5.5V VOUT = ± 12V
Transmitters Disable
Unit
mA
± 25
µA
Table 9: 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
4/15
Input Resistance
Max.
Unit
± 0.05
± 10
µA
0.4
V
VCC-0. VCC-0.1
6
-25
TA = 25°C VCC = 3.3V
0.6
1.1
TA = 25°C VCC = 5V
0.8
1.5
V
25
TA = 25°C VCC = 3.3V
1.5
2.4
1.2
2.4
0.3
TA = 25°C
3
5
V
V
TA = 25°C VCC = 5V
VRIHYS Input Hysteresis
RRIN
Typ.
V
V
7
KΩ
ST3237E
Table 10: 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
RL = 3KΩ CL= 250pF
one transmitter switching
VHSCI=VCC
VCC= 3 to 4.5V
RL = 3KΩ CL= 1000pF
one transmitter switching
VHSCI=VCC
VCC= 4.5 to 5.5V
Min.
Typ.
Max.
Unit
250
Kbps
1000
Kbps
1000
Kbps
0.15
µs
400
1000
ns
ns
300
ns
50
ns
100
ns
tPHLR
tPLHR
Propagation Delay Input to
Output
RIN to ROUT
CL = 150pF
tPHLR
tPLHR
Propagation Delay Input to
Output
CL = 1000pF
tT_SKEW Transmitter Skew
RL = 3kΩ
VHSCI=VCC
VHSCI=GND
|tPHL - tTLH|
|tPHL - tTLH|
VHSCI=VCC
tR_SKEW Receiver Skew
|tPHL - tTLH|
Normal Operation
50
ns
Normal Operation
120
ns
tOER
tODR
SRT
Receiver Output Enable
Time
Receiver Output Disable
Time
Transition Slew Rate
VHSCI=GND
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
5/15
ST3237E
Figure 2: Application Circuits
Table 11: Capacitance Value (µF)
VCC
3.0 to
3.1 to
4.5 to
3.0 to
6/15
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 3: LOW Level Receiver Output Current
Figure 4: HIGH Level Receiver Output Current
Figure 5: 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.
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.
7/15
ST3237E
Figure 6: Human Body Model Circuit
Figure 7: 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
Figure 8: IEC 1000-4-2 Circuit
8/15
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.
ST3237E
Figure 9: IEC 1000-4-2 Current Waveform
Table 12: 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
9/15
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
10/15
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
11/15
ST3237E
Tape & Reel SO-28 MECHANICAL DATA
mm.
inch
DIM.
MIN.
A
TYP
MAX.
MIN.
330
MAX.
12.992
C
12.8
D
20.2
0.795
N
60
2.362
T
13.2
TYP.
0.504
30.4
0.519
1.197
Ao
10.8
11.0
0.425
0.433
Bo
18.2
18.4
0.716
0.724
Ko
2.9
3.1
0.114
0.122
Po
3.9
4.1
0.153
0.161
P
11.9
12.1
0.468
0.476
12/15
ST3237E
Tape & Reel SSOP28 MECHANICAL DATA
mm.
inch
DIM.
MIN.
A
TYP
MAX.
MIN.
330
MAX.
12.992
C
12.8
D
20.2
0.795
N
60
2.362
T
13.2
TYP.
0.504
22.4
0.519
0.882
Ao
8.4
8.6
0.331
0.339
Bo
10.7
10.9
0.421
0.429
Ko
2.9
3.1
0.114
0.122
Po
3.9
4.1
0.153
0.161
P
11.9
12.1
0.468
0.476
13/15
ST3237E
Table 13: Revision History
Date
Revision
21-Mar-2005
5
14/15
Description of Changes
TSSOP has been removed.
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.
The ST logo is a registered trademark of STMicroelectronics
All other names are the property of their respective owners
© 2005 STMicroelectronics - All Rights Reserved
STMicroelectronics group of companies
Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America
www.st.com
15/15