SP3238E
SIGNAL PROCESSING EXCELLENCE
Intelligent +3.0V to +5.5V RS-232 Transceivers
s
Meets true EIA/TIA-232-F Standards
from a +3.0V to +5.5V power supply
s
Interoperable with EIA/TIA-232 and
adheres to EIA/TIA-562 down to a +2.7V
power source
s
Auto-Online
™
circuitry automatically
wakes up from a 1µA shutdown
s
Minimum 250Kbps data rate under load
s
Regulated Charge Pump Yields Stable
RS-232 Outputs Regardless of V
CC
Variations
s
Enhanced ESD Specifications:
+15KV Human Body Model
+15KV IEC1000-4-2 Air Discharge
+8KV IEC1000-4-2 Contact Discharge
DESCRIPTION
The
SP3238E
device is an RS-232 transceiver solution intended for portable or hand-held
applications such as notebook and palmtop computers. The
SP3238E
uses an internal
high-efficiency, charge-pump power supply that requires only 0.1µF capacitors in 3.3V
operation. This charge pump and
Sipex's
driver architecture allow the
SP3238E
device to
deliver compliant RS-232 performance from a single power supply ranging from +3.0V to
+5.0V. The
SP3238E
is a 5-driver/3-receiver device, ideal for laptop/notebook computer and
PDA applications. The
SP3238E
includes one complementary receiver that remains alert to
monitor an external device's Ring Indicate signal while the device is shutdown.
The
Auto-Online
feature allows the device to automatically "wake-up" during a shutdown
state when an RS-232 cable is connected and a connected peripheral is turned on. Otherwise,
the device automatically shuts itself down drawing less than 1µA.
SELECTION TABLE
Device
SP3221E
SP3223E
SP3243E
SP3238E
Power Supplies
+3.0V to +5.5V
+3.0V to +5.5V
+3.0V to +5.5V
+3.0V to +5.5V
RS-232
Drivers
1
2
3
5
RS-232
Receivers
1
2
5
3
External
Components
4 capacitors
4 capacitors
4 capacitors
4 capacitors
Auto-Online
Circuitry
YES
YES
YES
YES
TTL 3-State
YES
YES
YES
YES
No. of
Pins
16
20
28
28
Applicable U.S. Patents - 5,306,954; and other patents pending.
SP3238EDS/04
SP3238E +3.0V to +5.5V RS-232 Transceivers
© Copyright 1999 Sipex Corporation
1
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation
of the device at these ratings or any other above those
indicated in the operation sections of the specifications
below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may
affect reliability and cause permanent damage to the
device.
V
CC
.......................................................-0.3V to +6.0V
V+ (NOTE 1).......................................-0.3V to +7.0V
V- (NOTE 1)........................................+0.3V to -7.0V
V+ + |V-| (NOTE 1)...........................................+13V
I
CC
(DC V
CC
or GND current).........................+100mA
Input Voltages
TxIN, ONLINE,
SHUTDOWN, EN ...............................-0.3V to +6.0V
RxIN...................................................................+15V
Output Voltages
TxOUT...............................................................+15V
RxOUT, STATUS.......................-0.3V to (V
CC
+ 0.3V)
Short-Circuit Duration
TxOUT.....................................................Continuous
Storage Temperature......................-65°C to +150°C
Power Dissipation per package
28-pin SSOP (derate 11.2mW/
o
C above +70
o
C).......900mW
28-pin TSSOP (derate 13.2mW/
o
C above +70
o
C)...1100mW
NOTE 1:
V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 15V.
SPECIFICATIONS
Unless otherwise noted, the following specifications apply for V
CC
= +3.0V to +5.5V with T
AMB
= T
MIN
to T
MAX
.
Typical values apply at V
CC
= +3.3V or +5.0V and T
AMB
= 25°C.
PARAMETER
DC CHARACTERISTICS
Supply Current,
Auto-Online
Supply Current, Shutdown
Supply Current,
Auto-Online
Disabled
MIN.
TYP.
MAX.
UNITS
µA
µA
mA
CONDITIONS
1.0
1.0
0.4
10
10
2.0
All RxIN open, ONLINE = GND,
SHUTDOWN = V
CC
SHUTDOWN = GND
ONLINE = SHUTDOWN = V
CC
,
no load
LOGIC INPUTS AND RECEIVER OUTPUTS
Input Logic Threshold
LOW
HIGH
Input Leakage Current
Output Leakage Current
Output Voltage LOW
Output Voltage HIGH
V
CC
- 0.6 V
CC
-0.1
0.8
2.4
+0.01
+0.05
+1.0
+10
0.4
µA
µA
V
V
TxIN, ONLINE, SHUTDOWN
T
AMB
= 25
O
C
Receivers Disabled
I
OUT
= 1.6mA
I
OUT
= 1.0mA
V
V
CC
= +3.3V or +5.0V, TxIN
ONLINE, SHUTDOWN
SP3238EDS/04
SP3238E +3.0V to +5.5V RS-232 Transceivers
© Copyright 1999 Sipex Corporation
2
Unless otherwise noted, the following specifications apply for V
CC
= +3.0V to +5.5V with T
AMB
= T
MIN
to T
MAX
.
Typical values apply at V
CC
= +3.3V or +5.0V and T
AMB
= 25°C.
SPECIFICATIONS (continued)
PARAMETER
DRIVER OUTPUTS
Output Voltage Swing
Output Resistance
Output Short-Circuit Current
Output Leakage Current
RECEIVER INPUTS
Input Voltage Range
Input Threshold LOW
Input Threshold LOW
Input Threshold HIGH
Input Threshold HIGH
Input Hysteresis
Input Resistance
MIN.
TYP.
MAX.
UNITS
CONDITIONS
±5.0
300
±5.4
V
Ω
All driver outputs loaded with 3K
Ω
to GND
V
CC
= V+ = V- = 0V, V
OUT
= ±2V
V
OUT
= GND
V
OUT
= ±15V
V
CC
= 0V or 3.0V to 5.5V,
V
OUT
= ±15V, Drivers disabled
±35
±70
±100
TBD
±25
mA
µA
-15
0.6
0.8
1.2
1.5
1.5
1.8
0.3
3
5
15
V
V
V
V
CC
= 3.3V
V
CC
= 5.0V
V
CC
= 3.3V
V
CC
= 5.0V
2.4
2.4
V
V
V
7
kΩ
Auto-Online
CIRCUITRY CHARACTERISTICS (ONLINE = GND, SHUTDOWN = V
CC
)
0. 4
V
CC
- 0.6
200
0.5
V
V
µS
µS
I
OUT
= 1.6mA
I
OUT
= -1.0mA
STATUS Output Voltage LOW
STATUS Output Voltage HIGH
Receiver Threshold to Drivers
Enabled (t
ONLINE
)
Receiver Positive or Negative
Threshold to STATUS HIGH
(t
STSH
)
Receiver Positive or Negative
Threshold to STATUS LOW
(t
STSL
)
Figure 15
Figure 15
20
µS
Figure 15
SP3238EDS/04
SP3238E +3.0V to +5.5V RS-232 Transceivers
© Copyright 1999 Sipex Corporation
3
SPECIFICATIONS (continued)
Unless otherwise noted, the following specifications apply for V
CC
= +3.0V to +5.5V with T
AMB
= T
MIN
to T
MAX
.
Typical values apply at V
CC
= +3.3V or +5.0V and T
AMB
= 25°C.
PARAMETER
TIMING CHARACTERISTICS
Maximum Data Rate
Receiver Propagation Delay
t
PHL
t
PLH
Receiver Output Enable Time
Receiver Output Disable Time
Driver Skew
Receiver Skew
Transition-Region Slew Rate
250
kbps
µs
ns
ns
500
1000
30
ns
ns
V/
µs
R
L
= 3k
Ω
, C
L
= 1000pF, one driver active
Receiver input to Receiver output, C
L
= 150pF
Normal operation
Normal operation
| t
PHL
- t
PLH
|, T
AMB
= 25
o
C
| t
PHL
- t
PLH
|
V
CC
= 3.3V, R
L
= 3k
Ω
, T
AMB
= 25
o
C,
measurements taken from -3.0V to +3.0V or
+3.0V to -3.0V
MIN.
TYP.
MAX.
UNITS
CONDITIONS
0.15
0.15
200
200
100
200
TYPICAL PERFORMANCE CHARACTERISTICS
Unless otherwise noted, the following performance characteristics apply for V
CC
= +3.3V, 235Kbps data rate, all drivers
loaded with 3kΩ, 0.1µF charge pump capacitors, and T
AMB
= +25°C.
14
6
12
10
Transmitter Output Voltage [V]
4
2
0
0
-2
-4
-6
Load Capacitance [pF]
500
1000
1500
Vout+
Vout-
Slew Rate [V/µs]
8
6
4
2
0
0
500
1000
1500
Load Capacitance [pF]
2000
+Slew
-Slew
Figure 1. Transmitter Output Voltage VS. Load
Capacitance
Figure 2. Slew Rate VS. Load Capacitance
SP3238EDS/04
SP3238E +3.0V to +5.5V RS-232 Transceivers
© Copyright 1999 Sipex Corporation
4
NAME
C2+
GND
C2-
V-
T
1
OUT
T
2
OUT
T
3
OUT
R
1
IN
R
2
IN
T
4
OUT
R
3
IN
T
5
OUT
ONLINE
SHUTDOWN
STATUS
R
1
OUT
T
5
IN
R
3
OUT
T
4
IN
R
2
OUT
R
1
OUT
T
3
IN
T
2
IN
T
1
IN
C1-
V
CC
V+
C1+
FUNCTION
Positive terminal of the inverting charge-pump capacitor.
Ground.
Negative terminal of the inverting charge-pump capacitor.
Regulated -5.5V output generated by the charge pump.
RS-232 driver output.
RS-232 driver output.
RS-232 driver output.
RS-232 receiver input.
RS-232 receiver input.
RS-232 driver output.
RS-232 receiver input.
RS-232 driver output.
Apply logic HIGH to override
Auto-Online
circuitry keeping drivers active
(SHUTDOWN must also be logic HIGH, refer to Table 2).
Apply logic LOW to shut down drivers and charge pump. This overrides all
Auto-
Online
circuitry and ONLINE (refer to Table 2).
TTL/CMOS Output indicating online and shutdown status.
Non-inverting receiver-1 output, active in shutdown.
TTL/CMOS driver input.
TTL/CMOS receiver output.
TTL/CMOS driver input.
TTL/CMOS receiver output.
TTL/CMOS receiver output.
TTL/CMOS driver input.
TTL/CMOS driver input.
TTL/CMOS driver input.
Negative terminal of the voltage doubler charge-pump capacitor.
+3.0V to +5.5V supply voltage.
Regulated +5.5V output generated by the charge pump.
Positive terminal of the voltage doubler charge-pump capacitor.
PIN
NO.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Table 1. Device Pin Description
SP3238EDS/04
SP3238E +3.0V to +5.5V RS-232 Transceivers
© Copyright 1999 Sipex Corporation
5