1
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
High Speed +3.0V to +5.5V RS-232 Driver/Receiver Pair
SP3220B/U
DESCRIPTION
Meets True RS-232 Protocol Operation
From A +3.0V to +5.5V Power Supply
Minimum 250 Kbps Data Rate
(SP3220B) or 1Mbps Data Rate
(SP3220U) under Fully Load
1
A Low-Power Shutdown With
Receivers Active
Interoperable With EIA/TIA - 232 and
adheres to EIA/TIA - 562 Down to
+2.7V Power Source
Pin-Compatible With The
MAX3221E Device Without
The
AUTO ON-LINE
Feature
ESD Specifications:
+2kV Human Body Model
The SP3220B/U device is an RS-232 driver/receiver solution intended for portable or hand-held
applications such as notebook or palmtop computers. The SP3220B/U device has a high-
efficiency, charge-pump power supply that requires only 0.1
F capacitors in 3.3V operation. This
charge pump allows the SP3220B/U device to deliver true RS-232 performance from a single
power supply ranging from +3.3V to +5.0V.
The SP3220B/U device has a low-power shutdown mode where the driver outputs and charge
pumps are disabled. During shutdown, the supply current falls to less than 1
A.
SP3220B/U
2
4
6
5
3
7
15
GND
T1IN
T1OUT
C1+
C1-
C2+
C2-
V+
V-
V
CC
11
0.1
F
0.1
F
0.1
F
+
C2
C5
C1
+
+
*C3
C4
+
+
0.1
F
0.1
F
13
RS-232
OUTPUTS
RS-232
INPUTS
LOGIC
INPUTS
V
CC
14
5k
R1IN
R1OUT
9
8
LOGIC
OUTPUTS
*can be returned to
either V
CC
or GND
EN
1
SHDN
16
SP3220B/U
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
2
NOTE 1: V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
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, EN .............................................. -0.3V to +6.0V
RxIN ................................................................... +25V
Output Voltages
TxOUT ............................................................. +13.2V
RxOUT ......................................... -0.3V to (V
CC
+0.3V)
Short-Circuit Duration
TxOUT ...................................................... Continuous
Storage Temperature ....................... -65
C to +150
C
Power Dissipation Per Package
16-pin SSOP (derate 9.69mW/
o
Cabove+70
o
C) ........ 775mW
16-pin TSSOP (derate 10.5mW/
o
C above +70
o
C) ..... 840mW
16-pin Wide SOIC (derate 11.2mW/
o
C above+70
o
C) 900mW
SPECIFICATIONS
Unless otherwise noted, the following specifications apply for V
CC
= +3.0V to +5.0V with T
AMB
= T
MIN
to T
MAX
.
Typical Values apply at V
CC
= +3.3V or +5.0V and T
AMB
= 25
o
C, C1-4=0.1
F.
R
E
T
E
M
A
R
A
P
.
N
I
M
.
P
Y
T
.
X
A
M
S
T
I
N
U
S
N
O
I
T
I
D
N
O
C
S
C
I
T
S
I
R
E
T
C
A
R
A
H
C
C
D
t
n
e
r
r
u
C
y
l
p
p
u
S
3
.
0
0
.
1
A
m
T
,
d
a
o
l
o
n
B
M
A
5
2
+
=
o
V
,
C
C
C
V
3
.
3
=
V
r
o
D
N
G
=
N
I
x
T
C
C
t
n
e
r
r
u
C
y
l
p
p
u
S
n
w
o
d
t
u
h
S
0
.
1
0
1
A
,
D
N
G
=
N
D
H
S
T
B
M
A
5
2
+
=
o
V
,
C
C
C
V
3
.
3
+
=
V
r
o
V
0
=
N
I
x
T
C
C
S
T
U
P
T
U
O
R
E
V
I
E
C
E
R
D
N
A
S
T
U
P
N
I
C
I
G
O
L
W
O
L
d
l
o
h
s
e
r
h
T
c
i
g
o
L
t
u
p
n
I
8
.
0
V
2
e
t
o
N
,
N
D
H
S
,
N
E
,
N
I
x
T
H
G
I
H
d
l
o
h
s
e
r
h
T
c
i
g
o
L
t
u
p
n
I
0
.
2
V
V
C
C
r
o
2
e
t
o
N
,
V
3
.
3
=
2
e
t
o
N
,
V
0
.
5
t
n
e
r
r
u
C
e
g
a
k
a
e
L
t
u
p
n
I
1
0
.
0
0
.
1
A
,
N
D
H
S
,
N
E
,
N
I
x
T
T
B
M
A
5
2
+
=
o
V
C
N
I
V
o
t
V
0
=
C
C
t
n
e
r
r
u
C
e
g
a
k
a
e
L
t
u
p
t
u
O
5
0
.
0
0
1
A
V
d
e
l
b
a
s
i
D
s
r
e
v
i
e
c
e
R
T
U
O
V
o
t
V
0
=
C
C
W
O
L
e
g
a
t
l
o
V
t
u
p
t
u
O
4
.
0
V
I
T
U
O
A
m
6
.
1
=
H
G
I
H
e
g
a
t
l
o
V
t
u
p
t
u
O
V
C
C
6
.
0
-
V
C
C
1
.
0
-
V
I
T
U
O
A
m
0
.
1
-
=
S
T
U
P
T
U
O
R
E
V
I
R
D
g
n
i
w
S
e
g
a
t
l
o
V
t
u
p
t
u
O
0
.
5
4
.
5
V
k
3
,
s
t
u
p
t
u
o
r
e
v
i
r
d
ll
a
t
a
d
n
u
o
r
g
o
t
d
a
o
l
T
B
M
A
5
2
+
=
o
C
e
c
n
a
t
s
i
s
e
R
t
u
p
t
u
O
0
0
3
V
C
C
T
,
V
0
=
-
V
=
+
V
=
T
U
O
= + V
2
t
n
e
r
r
u
C
t
i
u
c
r
i
C
-
t
r
o
h
S
t
u
p
t
u
O
5
3
0
6
A
m
V
T
U
O
V
0
=
t
n
e
r
r
u
C
e
g
a
k
a
e
L
t
u
p
t
u
O
5
2
A
V
T
U
O
= +
V
,
V
2
1
C
C
d
e
l
b
a
s
i
d
s
r
e
v
i
r
d
,
V
5
.
5
o
t
V
0
=
3
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
SPECIFICATIONS (continued)
Unless otherwise noted, the following specifications apply for V
CC
= +3.0V to +5.0V with T
AMB
= T
MIN
to T
MAX
.
Typical Values apply at V
CC
= +3.3V or +5.0V and T
AMB
= 25
o
C, C1-4=0.1
F.
NOTE 2: Driver input hysteresis is typically 250mV.
R
E
T
E
M
A
R
A
P
.
N
I
M
.
P
Y
T
.
X
A
M
S
T
I
N
U
S
N
O
I
T
I
D
N
O
C
S
T
U
P
N
I
R
E
V
I
E
C
E
R
e
g
n
a
R
e
g
a
t
l
o
V
t
u
p
n
I
5
2
-
5
2
+
V
W
O
L
d
l
o
h
s
e
r
h
T
t
u
p
n
I
6
.
0
8
.
0
2
.
1
5
.
1
V
V
C
C
V
3
.
3
=
V
C
C
V
0
.
5
=
H
G
I
H
d
l
o
h
s
e
r
h
T
t
u
p
n
I
5
.
1
8
.
1
4
.
2
4
.
2
V
V
C
C
V
3
.
3
=
V
C
C
V
0
.
5
=
s
i
s
e
r
e
t
s
y
H
t
u
p
n
I
3
.
0
V
e
c
n
a
t
s
i
s
e
R
t
u
p
n
I
3
5
7
k
S
C
I
T
S
I
R
E
T
C
A
R
A
H
C
G
N
I
M
I
T
e
t
a
R
a
t
a
D
m
u
m
i
x
a
M
0
5
2
s
p
b
K
R
L
k
3
=
C
,
L
)
B
E
0
2
2
3
P
S
(
F
p
0
0
0
1
=
e
t
a
R
a
t
a
D
m
u
m
i
x
a
M
0
0
0
1
s
p
b
K
R
L
k
3
=
C
,
L
)
U
E
0
2
2
3
P
S
(
F
p
0
5
2
=
r
e
v
i
e
c
e
R
y
a
l
e
D
n
o
i
t
a
g
a
p
o
r
P
r
5
1
.
0
5
1
.
0
s
s
t
L
H
P
C
,
T
U
O
x
R
o
t
N
I
x
R
,
L
F
p
0
5
1
=
t
L
H
P
C
,
T
U
O
x
R
o
t
N
I
x
R
,
L
F
p
0
5
1
=
e
m
i
T
e
l
b
a
n
E
t
u
p
t
u
O
r
e
v
i
e
c
e
R
0
0
2
s
n
e
m
i
T
e
l
b
a
s
i
D
t
u
p
t
u
O
r
e
v
i
e
c
e
R
0
0
2
s
n
w
e
k
S
r
e
v
i
r
D
0
0
1
s
n
t
|
L
H
P
t
-
H
L
P
T
,
|
B
M
A
5
2
=
o
C
w
e
k
S
r
e
v
i
e
c
e
R
0
5
s
n
t
|
L
H
P
t
-
H
L
P
|
e
t
a
R
w
e
l
S
n
o
i
g
e
R
-
n
o
i
t
i
s
n
a
r
T
0
9
0
3
/
V
s
/
V
s
V
C
C
R
,
V
3
.
3
=
L
K
3
=
T
,
B
M
A
5
2
=
o
,
C
V
0
.
3
+
o
t
V
0
.
3
-
m
o
r
f
n
e
k
a
t
s
t
n
e
m
e
r
u
s
a
e
m
)
B
E
0
2
2
3
P
S
(
V
0
.
3
-
o
t
V
0
.
3
+
r
o
)
U
E
0
2
2
3
P
S
(
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
4
TYPICAL PERFORMANCE CHARACTERISTICS
Unless otherwise noted, the following performance characteristics apply for V
CC
= +3.3V, 250kbps data rates, all drivers
loaded with 3k
, 0.1F charge pump capacitors, and T
AMB
= +25
C.
30
25
20
15
10
5
0
Icc (mA)
Load Capacitance (pF)
0
1000
2000
3000
4000
5000
125Kbps
20Kbps
60Kbps
T1 at Full Data Rate
T2 at 1/16 Full Data Rate
T1+T2 Loaded with 3k/CLoad
6
4
2
0
-2
-4
-6
0
1000
2000
3000
4000
5000
TxOUT +
TxOUT -
Transmitter Output
Voltage (V)
Load Capacitance (pF)
T1 at 250Kbps
2.7
3
3.5
4
4.5
5
Supply Voltage (V)
Tr
ansmitter Output
Vo
ltage (V)
6
4
2
0
-2
-4
-6
TxOUT +
TxOUT -
12
10
8
6
4
2
0
2.7
3
3.5
4
4.5
5
Supply Current (mA)
Supply Voltage (V)
T1 Loaded with 3K // 1000pf @ 250Kbps
25
20
15
10
5
0
0
500
1000
2000
3000
4000
5000
Slew rate (V/s)
Load Capacitance (pF)
- Slew
+ Slew
40
30
20
10
0
0
250
500
1000
2000
3000
4000
Icc (mA)
Load Capacitance (pF)
500Kbps
1Mbps
2Mbps
Figure 1. I
CC
vs Load Capacitance for the SP3220B.
Figure 2. Transmiter Output Voltage vs Load Capacitance
for the SP3220B..
Figure 3. Transmitter Output Voltage vs Supply Voltage
for the SP3220B.
Figure 4. Supply Current vs Supply Voltage for the
SP3220B.
Figure 5. Slew Rate vs Load Capacitance for the
SP3220B.
Figure 4. Supply Current vs Supply Voltage for the
SP3220U.
5
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
TYPICAL PERFORMANCE CHARACTERISTICS: Continued
Unless otherwise noted, the following performance characteristics apply for V
CC
= +3.3V, 250kbps data rates, all drivers
loaded with 3k
, 0.1F charge pump capacitors, and T
AMB
= +25
C.
Figure 7. Transmitter Output Voltage vs Load Capaci-
tance for the SP3220U.
Figure 8. Transmiter Output Voltage vs Supply Voltage
for the SP3220U.
Figure 9. Supply Current vs Supply Voltage for the
SP3220U.
0
250
500
1000
1500
2000
Load Capacitance (pF)
Tr
ansmitter
Output V
o
ltage (V)
6
4
2
0
-2
-4
-6
2Mbps
1.5Mbps
1Mbps
2Mbps
1.5Mbps
1Mbps
2.5
2.7
3
3.5
4
4.5
5
Supply Voltage (V)
Tr
ansmitter Output
Vo
ltage (V)
6
4
2
0
-2
-4
-6
TxOUT +
TxOUT -
16
14
12
10
8
6
4
2
0
2.7
3
3.5
4
4.5
5
Supply Current (mA)
Supply Voltage (V)
T1 Loaded with 3K // 1000pf @1Mbps
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
6
Table 1. Device Pin Description
E
M
A
N
N
O
I
T
C
N
U
F
R
E
B
M
U
N
N
I
P
N
E
-
i
r
T
o
t
H
G
I
H
e
v
i
r
D
.
n
o
i
t
a
r
e
p
o
l
a
m
r
o
n
r
o
f
W
O
L
e
v
i
r
D
.
l
o
r
t
n
o
C
e
l
b
a
n
E
r
e
v
i
e
c
e
R
.
)
e
t
a
t
s
Z
-
h
g
i
h
(
s
t
u
p
t
u
o
r
e
v
i
e
c
e
r
e
h
t
e
t
a
t
S
1
+
1
C
.
r
o
t
i
c
a
p
a
c
p
m
u
p
-
e
g
r
a
h
c
r
e
l
b
u
o
d
e
g
a
t
l
o
v
e
h
t
f
o
l
a
n
i
m
r
e
t
e
v
i
t
i
s
o
P
2
+
V
.
p
m
u
p
e
g
r
a
h
c
e
h
t
y
b
d
e
t
a
r
e
n
e
g
V
5
.
5
+
3
-
1
C
.
r
o
t
i
c
a
p
a
c
p
m
u
p
-
e
g
r
a
h
c
r
e
l
b
u
o
d
e
g
a
t
l
o
v
e
h
t
f
o
l
a
n
i
m
r
e
t
e
v
i
t
a
g
e
N
4
+
2
C
.
r
o
t
i
c
a
p
a
c
p
m
u
p
-
e
g
r
a
h
c
g
n
i
t
r
e
v
n
i
e
h
t
f
o
l
a
n
i
m
r
e
t
e
v
i
t
i
s
o
P
5
-
2
C
.
r
o
t
i
c
a
p
a
c
p
m
u
p
-
e
g
r
a
h
c
g
n
i
t
r
e
v
n
i
e
h
t
f
o
l
a
n
i
m
r
e
t
e
v
i
t
a
g
e
N
6
-
V
.
p
m
u
p
e
g
r
a
h
c
e
h
t
y
b
d
e
t
a
r
e
n
e
g
V
5
.
5
-
7
N
I
1
R
.
t
u
p
n
i
r
e
v
i
e
c
e
r
2
3
2
-
S
R
8
T
U
O
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u
s
6
1
7
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
Figure 10. Pinout Configurations for the SP3220B/U
V-
1
2
3
4
13
14
15
16
5
6
7
12
11
10
C1+
V+
C1-
C2+
C2-
R1IN
GND
V
CC
T1OUT
No Connect
8
9
SP3220B/U
T1IN
No Connect
R1OUT
EN
SHDN
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
8
Figure 11. SP3220B/U Typical Operating Circuits
SP3220B/U
2
4
6
5
3
7
15
GND
T1IN
T1OUT
C1+
C1-
C2+
C2-
V+
V-
V
CC
11
0.1
F
0.1
F
0.1
F
+
C2
C5
C1
+
+
*C3
C4
+
+
0.1
F
0.1
F
13
RS-232
OUTPUTS
RS-232
INPUTS
LOGIC
INPUTS
V
CC
14
5k
R1IN
R1OUT
9
8
LOGIC
OUTPUTS
*can be returned to
either V
CC
or GND
EN
1
SHDN
16
9
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
DESCRIPTION
The SP3220B/U device meets the EIA/TIA-232
and V.28/V.24 communication protocols and
can be implemented in battery-powered,
portable, or hand-held applications such as
notebook or palmtop computers. The SP3220B/
U device features Sipex's proprietary on-board
charge pump circuitry that generates 2 x V
CC
for
RS-232 voltage levels from a single +3.0V to
+5.5V power supply. This series is ideal for
+3.3V-only systems, mixed +3.0V to +5.5V
systems, or +5.0V-only systems that require true
RS-232 performance. The SP3220B device has
a driver that can operate at a data rate of 250Kbps
fully loaded. The SP3220U can Operate at
1000Kbps
The SP3220B/U is a 1-driver/1-receiver device
ideal for portable or hand-held applications.
The SP3220B/U features a 1
A shutdown mode
that reduces power consumption and extends
battery life in portable systems. Its receivers
remain active in shutdown mode, allowing
external devices such as modems to be
monitored using only 1
A supply current.
THEORY OF OPERATION
The SP3220B/U device is made up of three basic
circuit blocks: 1. Drivers, 2. Receivers, and 3.
the Sipex proprietary charge pump.
Drivers
The drivers are inverting level transmitters that
convert TTL or CMOS logic levels to +5.0V
EIA/TIA-232 levels inverted relative to the
input logic levels. Typically, the RS-232 output
voltage swing is +5.5V with no load and at least
+5V minimum fully loaded. The driver outputs
are protected against infinite short-circuits to
ground without degradation in reliability. Driver
outputs will meet EIA/TIA-562 levels of +3.7V
with supply voltages as low as 2.7V.
The SP3220B drivers typically can operate at a
data rate of 250Kbps fully loaded with 3K
in
parallel with 1000pF, ensuring compatibility
with PC-to-PC communication software.
The SP3220U drivers can guarantee a data rate
of 1000Kbps fully loaded with 3
in parallel
with 250pF.
The slew rate of the SP3220B output is internally
limited to a maximum of 30V/
s in order to meet
the EIA standards (EIA RS-232D 2.1.7,
Paragraph 5). The transition of the loaded output
from HIGH to LOW also meets the monotonicity
requirements of the standard.
Figure 12 shows a loopback circuit used to test
the RS-232 driver. Figure 13 shows the test
results of the loopback circuit with the SP3220B
driver active at 250Kbps with an RS-232 load in
parallel with a 1000pF capacitor. Figure 14
shows the test results where the SP3220U driver
was active at 1000Kbps and loaded with an RS-
232 receiver in parallel with a 250pF capacitor.
A solid RS-232 data transmission rate of 250Kbps
provides compatibility with many designs in
personal computer peripherals and LAN appli-
cations.
The SP3220B/U driver's output stage is turned
off (high-Z) when the device is in shutdown
mode. When the power is off, the SP3220B/U
device permits the outputs to be driven up to
+12V. The driver's input does not have pull-up
resistors. Designers should connect an unused
input to V
CC
or GND.
In the shutdown mode, the supply current falls to
less than 1
A, where SHDN = LOW. When the
SP3220B/U device is shut down, the device's
driver output is disabled (high-Z) and the charge
pump is turned off with V+ pulled down to V
CC
and V- pulled to GND. The time required to exit
shutdown is typically 100
s. Connect SHDN to
V
CC
if the shutdown mode is not used. SHDN has
no effect on RxOUT. Note that the driver is
enabled only when the magnitude of V- exceeds
approximately 3V.
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
10
Figure 13. SP3220B Driver Loopback Test Results at
250Kbps
Figure 14. SP3220U Driver Loopback Test Results at
1Mbps
Figure 12. SP3220B/U Driver Loopback Test Circuit
SP3220B/U
GND
TxIN
TxOUT
C1+
C1-
C2+
C2-
V+
V-
V
CC
0.1
F
0.1
F
0.1
F
+
C2
C5
C1
+
+
C3
C4
+
+
0.1
F
0.1
F
LOGIC
INPUTS
V
CC
5k
RxIN
RxOUT
LOGIC
OUTPUTS
EN
*SHDN
(SP3220B 1000pF)
(SP3220U 250pF)
V
CC
11
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
Table 2. Truth Table Logic for Shutdown and
Enable Control
N
D
H
S
N
E
T
U
O
x
T
T
U
O
x
R
0
0
e
t
a
t
s
-
i
r
T
e
v
i
t
c
A
0
1
e
t
a
t
s
-
i
r
T
e
t
a
t
s
-
i
r
T
1
0
e
v
i
t
c
A
e
v
i
t
c
A
1
1
e
v
i
t
c
A
e
t
a
t
s
-
i
r
T
Receivers
The receiver converts EIA/TIA-232 levels to
TTL or CMOS logic output levels. The receiver
has an inverting high-impedance output. This
receiver output (RxOUT) is at high-impedance
when the enable control EN = HIGH. In the
shutdown mode, the receiver can be active or
inactive. EN has no effect on TxOUT. The truth
table logic of the SP3220B/U driver and receiver
outputs can be found in Table 2.
Since receiver input is usually from a transmission
line where long cable lengths and system
interference can degrade the signal, the inputs
have a typical hysteresis margin of 300mV.
This ensures that the receiver is virtually
immune to noisy transmission lines. Should an
input be left unconnected, a 5k
pulldown
resistor to ground will commit the output of the
receiver to a HIGH state.
Charge Pump
The charge pump is a Sipexpatented design
(U.S. 5,306,954) and uses a unique approach
compared to older lessefficient designs. The
charge pump still requires four external
capacitors, but uses a fourphase voltage shifting
technique to attain symmetrical 5.5V power
supplies. The internal power supply consists of
a regulated dual charge pump that provides
output voltages 5.5V regardless of the input
voltage (V
CC
) over the +3.0V to +5.5V range.
In most circumstances, decoupling the power
supply can be achieved adequately using a 0.1
F
bypass capacitor at C5 (refer to Figures 11).
In applications that are sensitive to power-
supply noise, decouple V
CC
to ground with a
capacitor of the same value as charge-pump
capacitor C1. Physically connect bypass
capacitors as close to the IC as possible.
The charge pumps operate in a discontinuous
mode using an internal oscillator. If the output
voltages are less than a magnitude of 5.5V, the
charge pumps are enabled. If the output voltage
exceed a magnitude of 5.5V, the charge pumps
are disabled. This oscillator controls the four
phases of the voltage shifting. A description of
each phase follows.
Phase 1
-- V
SS
charge storage -- During this phase of
the clock cycle, the positive side of capacitors
C
1
and C
2
are initially charged to V
CC
. C
l
+
is then
switched to GND and the charge in C
1
is
transferred to C
2
. Since C
2
+
is connected to V
CC
,
the voltage potential across capacitor C
2
is now
2 times V
CC
.
Phase 2
-- V
SS
transfer -- Phase two of the clock
connects the negative terminal of C
2
to the V
SS
storage capacitor and the positive terminal of C
2
to GND. This transfers a negative generated
voltage to C
3
. This generated voltage is
regulated to a minimum voltage of -5.5V.
Simultaneous with the transfer of the voltage to
C
3
, the positive side of capacitor C
1
is switched
to V
CC
and the negative side is connected to GND.
Phase 3
-- V
DD
charge storage -- The third phase of the
clock is identical to the first phase -- the charge
transferred in C
1
produces V
CC
in the negative
terminal of C
1
, which is applied to the negative
side of capacitor C
2
. Since C
2
+
is at V
CC
, the
voltage potential across C
2
is 2 times V
CC
.
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
12
Phase 4
-- V
DD
transfer -- The fourth phase of the clock
connects the negative terminal of C
2
to GND,
and transfers this positive generated voltage
across C
2
to C
4
, the V
DD
storage capacitor. This
voltage is regulated to +5.5V. At this voltage,
the internal oscillator is disabled. Simultaneous
with the transfer of the voltage to C
4
, the positive
side of capacitor C
1
is switched to V
CC
and the
negative side is connected to GND, allowing the
charge pump cycle to begin again. The charge
pump cycle will continue as long as the
operational conditions for the internal oscillator
are present.
Since both V
+
and V
are separately generated
from V
CC
; in a noload condition V
+
and V
will
be symmetrical. Older charge pump approaches
that generate V
from V
+
will show a decrease in
the magnitude of V
compared to V
+
due to the
inherent inefficiencies in the design.
The clock rate for the charge pump typically
operates at 250kHz. The external capacitors can
be as low as 0.1
F with a 16V breakdown
voltage rating.
ESD Tolerance
The SP3220B/U device incorporates ruggedized
ESD cells on all driver output and receiver
input pins. The ESD structure is improved over
our previous family for more rugged applications
and environments sensitive to electro-static
discharges and associated transients.
The Human Body Model has been the generally
accepted ESD testing method for semiconductors.
This method is also specified in MIL-STD-883,
Method 3015.7 for ESD testing. The premise of
this ESD test is to simulate the human body's
potential to store electro-static energy and
discharge it to an integrated circuit. The
simulation is performed by using a test model as
shown in Figure 20. This method will test the
IC's capability to withstand an ESD transient
during normal handling such as in manufacturing
areas where the ICs tend to be handled
frequently.
13
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
V
CC
= +5V
5V
5V
+5V
V
SS
Storage Capacitor
V
DD
Storage Capacitor
C
1
C
2
C
3
C
4
+
+
+
+
Figure 15. Charge Pump -- Phase 1
Figure 16. Charge Pump -- Phase 2
V
CC
= +5V
10V
V
SS
Storage Capacitor
V
DD
Storage Capacitor
C
1
C
2
C
3
C
4
+
+
+
+
Figure 17. Charge Pump Waveforms
Figure 18. Charge Pump -- Phase 3
V
CC
= +5V
5V
+5V
5V
V
SS
Storage Capacitor
V
DD
Storage Capacitor
C
1
C
2
C
3
C
4
+
+
+
+
V
CC
= +5V
+10V
V
SS
Storage Capacitor
V
DD
Storage Capacitor
C
1
C
2
C
3
C
4
+
+
+
+
Figure 19. Charge Pump -- Phase 4
Ch1 2.00V
Ch2
2.00V M 1.00
s Ch1 5.48V
2
1
T
T
[
]
T
+6V
a) C
2+
b) C
2
-
GND
GND
-6V
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
14
For the Human Body Model, the current
limiting resistor (R
S
) and the source capacitor
(C
S
) are 1.5k
and 100pF, respectively.
R
C
C
S
R
S
SW1
SW2
R
C
Device
Under
Test
DC Power
Source
C
S
R
S
SW1
SW2
Figure 20. ESD Test Circuit for Human Body Model
15
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
D
E
H
PACKAGE: PLASTIC
SHRINK
SMALL OUTLINE
(SSOP)
DIMENSIONS (Inches)
Minimum/Maximum
(mm)
20PIN
A
A1
L
B
e
A
A1
B
D
E
e
H
L
0.068/0.078
(1.73/1.99)
0.002/0.008
(0.05/0.21)
0.010/0.015
(0.25/0.38)
0.278/0.289
(7.07/7.33)
0.205/0.212
(5.20/5.38)
0.0256 BSC
(0.65 BSC)
0.301/0.311
(7.65/7.90)
0.022/0.037
(0.55/0.95)
0/8
(0/8)
24PIN
0.068/0.078
(1.73/1.99)
0.002/0.008
(0.05/0.21)
0.010/0.015
(0.25/0.38)
0.317/0.328
(8.07/8.33)
0.205/0.212
(5.20/5.38)
0.0256 BSC
(0.65 BSC)
0.301/0.311
(7.65/7.90)
0.022/0.037
(0.55/0.95)
0/8
(0/8)
28PIN
0.068/0.078
(1.73/1.99)
0.002/0.008
(0.05/0.21)
0.010/0.015
(0.25/0.38)
0.397/0.407
(10.07/10.33)
0.205/0.212
(5.20/5.38)
0.0256 BSC
(0.65 BSC)
0.301/0.311
(7.65/7.90)
0.022/0.037
(0.55/0.95)
0/8
(0/8)
16PIN
0.068/0.078
(1.73/1.99)
0.002/0.008
(0.05/0.21)
0.010/0.015
(0.25/0.38)
0.239/0.249
(6.07/6.33)
0.205/0.212
(5.20/5.38)
0.0256 BSC
(0.65 BSC)
0.301/0.311
(7.65/7.90)
0.022/0.037
(0.55/0.95)
0/8
(0/8)
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
16
D
E
H
PACKAGE: PLASTIC
SMALL OUTLINE (SOIC)
DIMENSIONS (Inches)
Minimum/Maximum
(mm)
A
A1
L
B
e
A
A1
B
D
E
e
H
L
16PIN
0.090/0.104
(2.29/2.649)
0.004/0.012
(0.102/0.300)
0.013/0.020
(0.330/0.508)
0.398/0.413
(10.10/10.49)
0.291/0.299
(7.402/7.600)
0.050 BSC
(1.270 BSC)
0.394/0.419
(10.00/10.64)
0.016/0.050
(0.406/1.270)
0/8
(0/8)
18PIN
0.090/0.104
(2.29/2.649))
0.004/0.012
(0.102/0.300)
0.013/0.020
(0.330/0.508)
0.447/0.463
(11.35/11.74)
0.291/0.299
(7.402/7.600)
0.050 BSC
(1.270 BSC)
0.394/0.419
(10.00/10.64)
0.016/0.050
(0.406/1.270)
0/8
(0/8)
17
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
PACKAGE:
PLASTIC THIN SMALL
OUTLINE
(TSSOP)
DIMENSIONS
in inches (mm)
Minimum/Maximum
16PIN
A
A1
L
B
e
A
A1
B
D
E
e
E2
L
- /0.043
(- /1.10)
0.002/0.006
(0.05/0.15)
0.007/0.012
(0.19/0.30)
0.193/0.201
(4.90/5.10)
0.169/0.177
(4.30/4.50)
0.026 BSC
(0.65 BSC)
0.126 BSC
(3.20 BSC)
0.020/0.030
(0.50/0.75)
0
/8
E2
D
- /0.043
(- /1.10)
0.002/0.006
(0.05/0.15)
0.007/0.012
(0.19/0.30)
0.252/0.260
(6.40/6.60)
0.169/0.177
(4.30/4.50)
0.026 BSC
(0.65 BSC)
0.126 BSC
(3.20 BSC)
0.020/0.030
(0.50/0.75)
0
/8
20PIN
E
Rev. 7/8/03 SP3220B/U +3.0 to +5.0V RS-232 Transceivers
Copyright 2003 Sipex Corporation
18
ORDERING INFORMATION
Model
Temperature Range
Package Type
SP3220BCA ............................................. 0C to +70C .......................................... 16-Pin SSOP
SP3220BCT ............................................. 0C to +70C .................................. 16-Pin Wide SOIC
SP3220BCY ............................................. 0C to +70C ........................................ 16-Pin TSSOP
SP3220BEA ............................................ -40C to +85C ........................................ 16-Pin SSOP
SP3220BET ............................................ -40C to +85C ................................ 16-Pin Wide SOIC
SP3220BEY ............................................ -40C to +85C ...................................... 16-Pin TSSOP
SP3220UCA ............................................. 0C to +70C .......................................... 16-Pin SSOP
SP3220UCT ............................................. 0C to +70C .................................. 16-Pin Wide SOIC
SP3220UCY ............................................. 0C to +70C ........................................ 16-Pin TSSOP
SP3220UEA ............................................ -40C to +85C ........................................ 16-Pin SSOP
SP3220UET ............................................ -40C to +85C ................................ 16-Pin Wide SOIC
SP3220UEY ............................................ -40C to +85C ...................................... 16-Pin TSSOP
Corporation
ANALOG EXCELLENCE
Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the
application or use of any product or circuit described hereing; neither does it convey any license under its patent rights nor the rights of others.
Sipex Corporation
Headquarters and
Sales Office
233 South Hillview Drive
Milpitas, CA 95035
TEL: (408) 934-7500
FAX: (408) 935-7600
Sales Office
22 Linnell Circle
Billerica, MA 01821
TEL: (978) 667-8700
FAX: (978) 670-9001
e-mail: sales@sipex.com
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