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March 2003
s
ESD PROTECTIO FOR RS-232 I/O PINS
15KV HUMAN BODY MODEL
8KV IEC 1000-4-2 CONTACT DISCHARGE
s
300
A SUPPLY CURRENT
s
250Kbps MINIMUM GUARENTEED DATA
RATE
s
6V/
s MINIMUM GUARANTEED SLEW RATE
s
MEET EIA/TIA-232 SPECIFICATIONS DOWN
TO 3V
s
AVAILABLE IN SO-18, SSOP20 AND
TSSOP20
DESCRIPTION
The ST3222E is a 3V powered EIA/TIA-232 and
V.28/V.24 communications interface with low
power requirements, high data-rate capabilities
and enhanced electrostatic discharge (ESD)
protection to 8kV using IEC1000-4-2 Contact
Discharge and 15kV using the Human Body
Model. ST3222E has a proprietary low dropout
transmitter output stage providing true RS-232
performance from 3 to 5V supplies with a dual
charge pump. The charge pump requires only four
small 0.1mF external capacitors for operation form
3V supply.
The device has two receivers and two drivers. The
ST3222E features a 1
A shutdown mode that
reduces power consumption and extends battery
life in portable systems. Its receivers can remain
active in shutdown mode, allowing external
devices such as modems to be monitored using
only 1
A supply current.
The device is guaranteed to run at data rates of
250Kbps while maintaining RS-232 output levels.
Typical applications are Notebook, Subnotebook
and
Palmtop
Computers,
Battery
Powered
Equipment, Hand-Held Equipment, Peripherals
and Printers.
ORDERING CODES
Type
Temperature
Range
Package
Comments
ST3222ECD
0 to 70 C
SO-18 (Tube)
50parts per tube / 20tube per box
ST3222EBD
-40 to 85 C
SO-18 (Tube)
50parts per tube / 20tube per box
ST3222ECDR
0 to 70 C
SO-18 (Tape & Reel)
1000 parts per reel
ST3222EBDR
-40 to 85 C
SO-18 (Tape & Reel)
1000 parts per reel
ST3222ECPR
0 to 70 C
SSOP20 (Tape & Reel)
1350 parts per reel
ST3222EBPR
-40 to 85 C
SSOP20 (Tape & Reel)
1350 parts per reel
ST3222ECTR
0 to 70 C
TSSOP20 (Tape & Reel)
2500 parts per reel
ST3222EBTR
-40 to 85 C
TSSOP20 (Tape & Reel)
2500 parts per reel
ST3222E
15KV ESD-PROTECTED, 3 TO 5.5V, LOW POWER,
UP TO 250KBPS, RS-232 DRIVERS AND RECEIVERS
SOP
SSOP
TSSOP
ST3222E
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PIN CONFIGURATION
PIN DESCRIPTION
PlN N
(SO-18)
PlN N
(SSOP20 TSSP20)
SYMBOL
NAME AND FUNCTION
1
1
EN
Receiver Enable Control. Drive low for normal
operation. Drive high to force the receivers outputs
(R_OUT) into a high-impedance state.
2
2
C
1
+
Positive Terminal for the first Charge Pump
Capacitor
3
3
V+
5.5V Generated By The Charge Pump.
4
4
C
1
-
Negative Terminal for the first Charge Pump
Capacitor
5
5
C
2
+
Positive Terminal for the second Charge Pump
Capacitor
6
6
C
2
-
Negative Terminal for the second Charge Pump
Capacitor
7
7
V-
-5.5V Generated By The Charge Pump.
8
8
T2
OUT
Second Transmitter Output Voltage
9
9
R2
IN
Second Receiver Input Voltage
10
10
R2
OUT
Second Receiver Output Voltage
11
NC
Not Connected
11
12
T2
IN
Second Transmitter Input Voltage
12
13
T1
IN
First Transmitter Input Voltage
14
NC
Not Connected
13
15
R1
OUT
First Receiver Output Voltage
14
16
R1
IN
First Receiver Input Voltage
15
17
T1
OUT
First Transmitter Output Voltage
16
18
GND
Ground
17
19
V
CC
Supply Voltage
18
20
SHDN
Active Low Shutdown Control Input. Drive Low To
Shut-down Transmittes And Charge Pump
SO-18
SSOP20/TSSOP20
ST3222E
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ABSOLUTE MAXIMUM RATINGS
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
ESD PERFORMANCE: TRANSMITTER OUTPUTS, RECEIVER INPUTS
ELECTRICAL CHARACTERISTICS
(C
1
- C
4
= 0.1
F, V
CC
= 3V to 5.5V, T
A
= -40 to 85C, unless otherwise specified.
Typical values are referred to T
A
= 25C)
LOGIC INPUT ELECTRICAL CHARACTERISTICS
(C
1
- C
4
= 0.1
F, V
CC
= 3V to 5.5V, T
A
= -40 to 85C, unless otherwise specified.
Typical values are referred to T
A
= 25C)
Note 1: Transmitter input hysteresis is typically 250mV
Symbol
Parameter
Value
Unit
V
CC
Supply Voltage
-0.3 to 6
V
V+
Doubled Voltage Terminal
(V
CC
- 0.3) to 7
V
V-
Inverted Voltage Terminal
0.3 to -7
V
V+ +|V-|
13
V
T
IN
Transmitter Input Voltage Range
-0.3 to 6
V
SHDN
Transmitter Input Voltage Range
-0.3 to 6
V
R
IN
Receiver Input Voltage Range
25
V
T
OUT
Transmitter Output Voltage Range
13.2
V
R
OUT
Receiver Output Voltage Range
-0.3 to (V
CC
+ 0.3)
V
t
SHORT
Transmitter Output Short to GND Time
Continuous
SHDN
EN
T-OUT
R-OUT
0
0
High Z
Active
0
1
High Z
High Z
1
0
Active
Active
1
1
Active
High Z
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
ESD
ESD Protection Voltage
Human Body Model
15
kV
ESD
ESD Protection Voltage
IEC-1000-4-2
8
kV
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
I
SUPPLY
V
CC
Power Supply Current
No Load
SHDN=V
CC
T
A
= 25C
0.3
1
mA
I
SHDN
SHUTDOWN Supply
Current
No Load
SHDN=V
CC
T
A
= 25C
1
10
A
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
IL
Input Logic Threshold Low
T-IN, EN, SHDN (Note 1)
0.8
V
V
IH
Input Logic Threshold High
V
CC
= 3.3V
2
V
V
CC
= 5V
2.4
V
HYS
Transmitter Input
Histeresys
0.25
V
I
IL
Input Leakage Current
T-IN, EN, SHDN
0.01
1
A
ST3222E
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TRANSMITTER ELECTRICAL CHARACTERISTICS
(C
1
- C
4
= 0.1
F V
CC
= 3V to 5.5V, T
A
= -40 to 85C, unless otherwise specified.
Typical values are referred to T
A
= 25C)
RECEIVER ELECTRICAL CHARACTERISTICS
(C
1
- C
4
= 0.1
F V
CC
= 3V to 5.5V, T
A
= -40 to 85C, unless otherwise specified.
Typical values are referred to T
A
= 25C)
TIMING CHARACTERISTICS
(C
1
- C
4
= 0.1
F, V
CC
= 3V to 5.5V, T
A
= -40 to 85C, unless otherwise specified.
Typical values are referred to T
A
= 25C)
(Note 1) Transmitter Skew is measured at the transmitter zero cross points
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
TOUT
Output Voltage Swing
All Transmitter outputs are loaded with
3K
to GND
5
5.4
V
R
TOUT
Transmitter Output
Resistance
V
CC
= V+ = V- = 0V
V
OUT
=
2V
300
10M
I
TSC
Output Short Circuit Current
60
mA
I
TOL
Output Leakage Current
V
CC
= 0V or 3V to 3.6V
V
OUT
=
12V
Transmitters Disable
25
A
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
I
OL
Output Leakage Current
R-OUT, EN = V
CC
, Receiver Disabled
0.05
10
A
V
RIN
Receiver Input Voltage
Operating Range
-25
25
V
V
RIL
Input Threshold Low
T
A
= 25C
V
CC
= 3.3V
0.6
1.2
V
T
A
= 25C
V
CC
= 5V
0.8
1.5
V
RIH
Input Threshold High
T
A
= 25C
V
CC
= 3.3V
1.5
2.4
V
T
A
= 25C
V
CC
= 5V
1.8
2.4
V
RIHYS
Input Hysteresis
0.5
V
R
RIN
Input Resistance
T
A
= 25C
3
5
7
K
V
ROL
Output Voltage Low
I
OUT
= 1.6mA
0.4
V
V
ROH
Output Voltage High
I
OUT
= -1mA
V
CC
-0.6 V
CC
-0.1
V
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
D
R
Data Transfer Rate
R
L
= 3K
C
L2
= 1000pF
one trasmitter switching
250
Kbps
t
PHLR
t
PLHR
Propagation Delay Input to
Output
R
XIN
to R
XOUT
C
L
= 150pF
0.15
s
|t
PHLT
- t
THL
|
Transmitter Propagation
Delay Difference
(Note 1)
200
ns
t
OER
Receiver Output Enable
Time
Normal Operation
50
ns
t
ODR
Receiver Output Disable
Time
Normal Operation
50
ns
|t
PHLR
- t
THR
|
Receiver Propagation Delay
Difference
50
ns
S
RT
Trnasition Slew Rate
T
A
= 25C R
L
= 3K
to 7K
V
CC
= 3.3V
measured from +3V to -3V or -3V to +3V
C
L
= 150pF to 1000pF
C
L
= 150pF to 2500pF
6
4
30
30
V/
s
V/
s
ST3222E
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APPLICATION CIRCUITS
CAPACITANCE VALUE (
F)
V
CC
C1
C2
C3
C4
Cbypass
3.0 to 3.6
0.1
0.1
0.1
0.1
0.1
4.5 to 5.5
0.047
0.33
0.33
0.33
0.1
3.0 to 5.5
0.1
0.47
0.47
0.47
0.1
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