1/12
May 2002
s
1
A LOW POWER SHUTDOWN WITH
RECEIVERS ACTIVE
s
GUARENTEED DATA RATE
250Kbps (Normal Operation)
1Mbps (Very High Speed Operation)
s
GUARANTEED SLEW RATE RANGE
6V/
s (Normal Operation)
24V/
s (Very High Speed Operation)
s
0.1
F EXTERNAL CAPACITORS
s
FLOW-THROUGH PINOUT
s
500
A LOW SUPPLY CURRENT
s
MEET EIA/TIA-232 SPECIFICATIONS DOWN
TO 3V
s
AVAILABLE IN SO-28, SSOP-28 AND
TSSOP28
DESCRIPTION
The ST3237 is a 3V to 5.5V powered EIA/TIA-232
and V.28/V.24 communication interfaces high
data-rate capabilities. ST3237 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 maintaning RS-232 output
levels.
ORDERING CODES
(*) Available on request
Type
Temperature
Range
Package
Comments
ST3237CD
0 to 70 C
SO-28 (Tube)
27parts per tube / 12tube per box
ST3237BD
-40 to 85 C
SO-28 (Tube)
27parts per tube / 12tube per box
ST3237CDR
0 to 70 C
SO-28 (Tape & Reel)
1000 parts per reel
ST3237BDR
-40 to 85 C
SO-28 (Tape & Reel)
1000 parts per reel
ST3237CPR
0 to 70 C
SSOP-28 (Tape & Reel)
1350 parts per reel
ST3237BPR
-40 to 85 C
SSOP-28 (Tape & Reel)
1350 parts per reel
ST3237CTR (*)
0 to 70 C
TSSOP28 (Tape & Reel)
2500 parts per reel
ST3237BTR (*)
-40 to 85 C
TSSOP28 (Tape & Reel)
2500 parts per reel
ST3237
3 TO 5.5V, 250KBPS, RS-232
TRANSCEIVER WITH STAND-BY
SSOP
SOP
TSSOP
ST3237
2/12
PIN DESCRIPTION
PlN N
SYMBOL
NAME AND FUNCTION
1
C
2
+
Positive Terminal of Inverting Charge Pump Capacitor
2
GND
Ground
3
C
2
-
Negative Terminal of Inverting Charge Pump Capacitor
4
V-
5.5V Generated by the Charge Pump
5
T1
OUT
First Transmitter Output Voltage
6
T2
OUT
Second Transmitter Output Voltage
7
T3
OUT
Third Transmitter Output Voltage
8
R1
IN
First Receiver Input Voltage
9
R2
IN
Second Receiver Input Voltage
10
T4
OUT
Fourth Transmitter Output Voltage
11
R3
IN
Third Receiver Input Voltage
12
T5
OUT
Fifth Transmitter Output Voltage
13
EN
Receiver Enable, Active Low
14
SHDN
Shutdown Control, Active Low
15
VHSCI
Very High Speed Control Input. Connect to GND for normal
operation; connect to VCC for 1Mbps transmission rates.
16
R1
OUTB
Non Inverting Complementary Receiver Output. Always Active.
17
T5
IN
Fifth Transmitter Input Voltage
18
R3
OUT
Third Receiver Output Voltage
19
T4
IN
Fourth Transmitter Input Voltage
20
R2
OUT
Second Receiver Output Voltage
21
R1
OUT
First Receiver Output Voltage
22
T3
IN
Third Transmitter Input Voltage
23
T2
IN
Second Transmitter Input Voltage
24
T1
N
First Transmitter Input Voltage
25
C
1
-
Negative Terminal of Voltage- Charge Pump Capacitor
26
V
CC
Supply Voltage
27
V+
-5.5V Generated by the Charge Pump
28
C
1
+
Positive Terminal of Voltage- Charge Pump Capacitor
ST3237
3/12
PIN CONFIGURATION
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.
Symbol
Parameter
Value
Unit
V
CC
Supply Voltage
-0.3 to 6
V
V+
Doubled Voltage Terminal
-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, EN
-0.3 to 6
V
VHSCI
Very High Speed Control Input
-0.3 to (V
CC
+0.3)
V
R
IN
Receiver Input Voltage Range
25
V
T
OUT
Transmitter Output Voltage Range
13.2
V
R
OUT
R
OUTB
Receiver Output Voltage Range
-0.3 to (V
CC
+ 0.3)
V
t
SHORT
Short Circuit Durtion on T
OUT
(one at a time)
Continuous
T
stg
Storage Temperature Range
-65 to 150
C
ST3237
4/12
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
TRANSMITTER ELECTRICAL CHARACTERISTICS
(C
1
- C
4
= 0.1
F tested at 3.3V
10%, 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 tested at 3.3V
10%, V
CC
= 3V to 5.5V, T
A
= -40 to 85C, unless otherwise specified.
Typical values are referred to T
A
= 25C)
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
I
SUPPLY
V
CC
Power Supply Current
No Load V
CC
= 3V or 5.0V T
A
= 25C
0.5
2
mA
I
SHDN
Shutdown Supply Current
SHDN=GND T
A
= 25C
1
10
A
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
TIL
Input Logic Threshold Low
(Note 1)
T-IN, VHSCI, EN, SHDN
0.8
V
V
TIH
Input Logic Threshold High
(Note 1)
V
CC
= 3.3V
V
CC
= 5V
2
2.4
V
V
I
IL
Input Leakage Current
T-IN, VHSCI, EN, SHDN
0.01
1.0
A
I
OL
Output Leakage Current
Receiver Disabled
0.05
10
A
V
OL
Output Voltage Low
I
OUT
= 1.6mA
0.4
V
V
OH
Output Voltage High
I
OUT
= -1mA
V
CC
-0.6 V
CC
-0.1
V
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
3000
I
SC
Output Short Circuit Current
25
60
mA
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
RIN
Receiver Input Voltage
Operating Range
-25
25
V
V
RIL
RS-232 Input Threshold
Low
T
A
= 25C
V
CC
= 3.3V
T
A
= 25C
V
CC
= 5V
0.6
0.8
1.2
1.5
V
V
V
RIH
RS-232 Input Threshold
High
T
A
= 25C
V
CC
= 3.3V
T
A
= 25C
V
CC
= 5V
1.5
1.8
2.4
2.4
V
V
V
RIHYS
Input Hysteresis
0.3
V
R
RIN
Input Resistance
T
A
= 25C
3
5
7
K
ST3237
5/12
TIMING CHARACTERISTICS
(C
1
- C
4
= 0.1
F tested at 3.3V
10%, V
CC
= 3V to 5.5V, T
A
= -40 to 85C, unless otherwise specified.
Typical values are referred to T
A
= 25C)
Transmitter Skew is measured at the transmitter zero cross points
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
D
R
Maximum Data Rate
R
L
= 3K
C
L
= 1000pF
one trasmitter switching VHSCI=GND
250
Kbps
R
L
= 3K
C
L
= 250pF
one trasmitter switching VHSCI=V
CC
V
CC
= 3 to 5.55V
100
Kbps
t
PHLR
t
PLHR
Propagation Delay Input to
Output
R
IN
to R
OUT
C
L
= 150pF
0.15
s
t
T_SKEW
Transmitter Skew
|t
PHL
- t
TLH
|
VHSCI=GND
100
ns
|t
PHL
- t
TLH
|
VHSCI=V
CC
60
ns
t
R_SKEW
Receiver Skew
|t
PHL
- t
TLH
|
50
ns
t
OER
Receiver Output Enable
Time
Normal Operation
80
ns
t
ODR
Receiver Output Disable
Time
Normal Operation
130
ns
S
RT
Transition Slew Rate
T
A
= 25C R
L
= 3 to 7K
V
CC
= 3.3V
measured from +3V to -3V or -3V to +3V
C
L
= 150pF to 1000pF
VHSCI=GND
C
L
= 150pF to 1000pF
VHSCI=V
CC
C
L
= 150pF to 2500pF
VHSCI=GND
6
24
4
30
150
30
V/
s
V/
s
V/
s
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