SIPEX SP303

SP303
Corporation
SIGNAL PROCESSING EXCELLENCE
RS232/AppleTalk™ Serial Transceiver
■ Single chip serial transceiver supports
AppleTalkTM or RS-232 interface
■ Programmable Selection of Interface
■ 4 RS-232 Drivers and 4 RS-232
Receivers
■ Provides MacintoshTM type interface
■ ±30V Receiver Input Levels
■ Surface Mount Packaging
DESCRIPTION…
The SP303 is a single chip device that offers both RS-232 and AppleTalk™ interfaces. When
configured for RS-232 mode the SP303 has 4 drivers and 4 receivers. When the part is
programmed for AppleTalk mode, the SP303 supports Macintosh–type ports. All drivers and
receivers can operate at data rates up to 1 Mbps. The differential driver used for transmitting data
signals is equipped with a tri-state function. The SP303 is available in a 28–pin SOIC package
for operation over the commercial temperature range.
TOUTB1 TOUTB2 TOUTA1 TOUTA2
+5V INPUT
VCC
+12V INPUT
VDD
–12V INPUT
VEE SELECT
A
B
RINA1 RINA2
RINB1 RINB2
GND
R1
T1
T2
T3
Corporation
R3
R4
T4
SP303
TINB1 TINB2 TINA1 TINA2 TXEN
SIGNAL PROCESSING EXCELLENCE
R2
ROUTA1 ROUTA2 ROUTB1 ROUTB2
69
SPECIFICATIONS
(TMIN ≤T A ≤T MAX and nominal supply voltages unless otherwise noted)
PARAMETER
MIN.
TYP.
MAX.
RS--232 DRIVER
TTL Input Level
VIL
0
0.8
VIH
2.0
High Level Output
+5.0
Low Level Output
-5.0
Short Circuit Current
±30
Slew Rate
30
Transition Time
3
Maximum Transmission Rate 200
RS-232 RECEIVER
Input Voltage Range
–15
+15
Input High Threshold
+1.75
+2.5
Input Low Threshold
+0.75
+1.35
Input Impedance
3
7
TTL Output Level
VOL
0.4
VOH
2.4
Maximum Receiving Rate
200
DIFFERENTIAL DRIVER
TTL Input Level
VIL
0
0.8
VIH
2.0
High Level Output
+3.6
+6
Low Level Output
-3.6
-6
Differential Output
±3.6
(VEE+0.7V)
(VDD–0.7V)
Short Circuit Current
40
Output Current
±500
Leakage Current
0.05
±10
Transition Time
720
Maximum Transmission Rate 1000
DIFFERENTIAL RECEIVER
Common Mode Range
±7
Differential Input
±15
Differential Input Threshold
–0.2
+0.2
Input Voltage Hysteresis
30
Input Resistance
3
TTL Output Level
VOL
0.4
VOH
2.4
Maximum Receiving Rate
1000
Short Circuit Output Current
±120
SINGLE–ENDED RECEIVER
Input Threshold
–200
Input Voltage Hysteresis
30
Input Impedance
3
TTL Output Level
VOL
VOH
2.4
Maximum Transmission Rate 1000
POWER REQUIREMENTS
VDD = +12V, ±10%
VCC = +5V, ±10%
VEE = –12V, ±10%
70
+200
7
7
5
11
UNIT
V
V
V
V
mA
V/µs
µs
kbps
CONDITIONS
Note 1
RL = 3kΩ, VIN = 0.8V
RL = 3kΩ, VIN = 2.0V
VOUT = 0V
CL = 50pF, RL = 3kΩ; TA = 25°C
Note 2
Note 1
V
V
V
kΩ
V
V
kbps
Positive-going
Negative-going
CL ≤2,500pF; VSS ≤ VIN ≤ VDD
VCC =+4.75V, IOUT =+1.6mA
VCC =+4.75V, IOUT =-0.5mA
Note 3
V
V
V
V
V
V
mA
µA
µA
ns
kbps
V
V
V
mV
kΩ
V
V
kbps
mA
mV
mV
kΩ
0.4
V
V
kbps
15
7
20
mA
mA
mA
IOH = 8mA
IOL = –8mA
RL = 450Ω
RL = ∞
–0.25V ≤ VO ≤ 6V; Power off
TxEN=Vcc, ≤0≤TxDO≤6V, Note 4
RL =450Ω, CL =50pF; Note 5
Note 3
Note 6
Note 6
TA=25°C
VCM =0V TA=25°C
–7V≤VCM≤+7V
VCC =+4.75V, IOUT=+1.6mA
VCC =+4.75V, IOUT=–0.5mA
VOUT =0V
Note 3
TA 25°C
VCM 0V; TA=25°C
VCC =+4.75; IOUT=+1.6mA
VCC =+4.75; IOUT=–0.5mA
All Transmitter outputs RL=∞
TA=25°C
Corporation
SIGNAL PROCESSING EXCELLENCE
SPECIFICATIONS
(TMIN ≤TA ≤TMAX and nominal supply voltages unless otherwise noted)
PARAMETER
MIN.
TYP.
MAX.
ENVIRONMENTAL AND MECHANICAL
Operating Temperature
0
+70
Storage Temperature
–65
+150
Package
28–pin SOIC
Note:
1.
2.
3.
4.
5.
6.
UNIT
CONDITIONS
°C
°C
RS-232 Mode, SELA = SELB = GND.
VOUT from +3V to –3V or –3V to +3V.
Macintosh™ AppleTalk™ Mode, SELA = SELB = +5V.
Leakage current specification applies to both TxDO– and TxDO+; TA=+25°C only.
From 10% to 90% of steady state.
This is an absolute maximum rating. Normal operating levels are VIN ≤ 5V.
PINOUT
VDD
1
28
RINA2
2
27
ROUTA2
RINA1
3
26
ROUTA1
VCC
N.C.
4
25
N.C.
TOUTA2
5
24
TINA2
TOUTA1
6
23
TINA1
SELECTA
7
22
TXEN
SELECTB
8
21
N.C.
TOUTB1
9
20
TINB1
TOUTB2 10
19
TINB2
N.C. 11
18
N.C.
RINB1 12
17
ROUTB1
RINB2 13
16
ROUTB2
GND 14
15
VEE
SP303
PIN ASSIGNMENTS – RS232 MODE
Pin 1 — VDD — +12V Power Supply.
Pin 2 — RINA2 — DSR; RS-232 input.
Pin 3 — RINA1 — RXD; RS-232 input.
Pin 4 — N.C. — No Connection.
Pin 5 — TOUTA2 — RTS; RS-232 output.
Pin 6 — TOUTA1 — TXD; RS-232 output.
Pin 7 — SEL A — Select A; used with Select B
(pin 8) to select operating mode. Logic “0” on
both SEL A and SEL B selects RS-232 mode;
logic “1” on both SEL A and SEL B selects
AppleTalk™ mode.
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SIGNAL PROCESSING EXCELLENCE
Pin 8 — SEL B — Select B; used with Select A
(pin 7) to select operating mode. Logic “0” on
both SEL A and SEL B selects RS-232 mode;
logic “1” on both SEL A and SEL B selects
AppleTalk™ mode.
Pin 9— TOUTB1— DTR; RS-232 output.
Pin 10 — TOUTB2 — Rl; RS-232 output.
Pin 11 — N.C. — No Connection.
Pin 12— RINB1— CTS; RS-232 input.
Pin 13 — N.C. — No Connection.
Pin 14 — GND — Signal ground. Connected to
logic and chasis ground.
Pin 15 — VEE — –12V Power Supply.
Pin 16 — N.C. — No Connection.
Pin 17 — ROUTB1 — CTS; TTL Output to
UART.
Pin 18 — N.C. — No Connection.
Pin 19 — TOUTB2 — Rl; TTL input from
UART.
Pin 20 — TINB1 — DTR; TTL input from
UART.
Pin 21 — N.C. — No Connection.
Pin 22 — TxEN — Transmit Enable; Only
functional in Mac Mode.
Pin 23 — TINA1 — TXD; TTL input from
UART.
Pin 24 — N.C. — No Connection.
Pin 25 — N.C. — No Connection.
71
Pin 26 — ROUTA1 — RXD; TTL output to
UART.
Pin 27 — N.C. — No Connection.
Pin 28 — VCC — +5V Power Supply.
PIN ASSIGNMENTS — MACINTOSH™
APPLETALK™ MODE
Pin 1 — VDD — +12V Power Supply.
Pin 2 — RINA2 — Receive data; received at
UART’s RxD (non–inverted); VIH = 0.2V;
VIL = –0.2V; RIN =3kΩ minimum.
Pin 3 — RINA1 — Receive data; received at
UART’s RxD (inverted); V IH = 0.2V;
VIL = –0.2V; RIN =3kΩ minimum.
Pin 4 — N.C. — No Connection.
Pin 5 — TOUTA2 — Transmit data; driven from
UART’s TxD (non–inverted); tri–stated when
UART’s RTS is not asserted; VOH = 3.6V min;
VOL = –3.6V min; RL = 450Ω.
Pin 6 — TOUTA1 — Transmit data; driven from
UART’s TxD (inverted); tri–stated when RTS
is not asserted; VOH = 3.6V min; VOL = –3.6V
min RL = 450Ω.
Pin 7 — SEL A — Select A; used with Select B
(pin 8) to select operating mode. Logic “0” on
both SEL A and SEL B selects RS-232 mode;
logic “1” on both SEL A and SEL B selects
AppleTalk™ mode.
Pin 8 — SEL B — Select B; used with Select A
(pin 7) to select operating mode. Logic “0” on
both SEL A and SEL B selects RS-232 mode;
logic “1” on both SEL A and SEL B selects
AppleTalk™ mode.
Pin 9— TOUTB1— Handshake output; driven
from UART’s DTR (inverted) ;VOH = 3.6V min;
VOL = –3.6V min; RL = 450Ω.
Pin 10 — TOUTB2 — Handshake output; driven
from UART’s DTR (non–inverted); VOH = 3.6V
min; VOL = –3.6V min; RL = 450Ω.
Pin 11 — N.C. — No Connection.
Pin 12— RINB1— Handshake input or external
clock; received non–inverted at UART’s CTS
and TRxC; VIH = 0.2V; V IL = –0.2V; RIN =3kΩ
minimum.
Pin 13 — N.C. — No Connection.
Pin 14 — GND — Signal ground. Connected to
72
logic and chasis ground.
Pin 15 — VEE — –12V Power Supply.
Pin 16 — N.C. — No Connection.
Pin 17 — ROUTB1 — Receive handshake output; connects to UART’s CTS and TRxC.
Pin 18 — N.C. — No Connection.
Pin 19 — TOUTB2 — Not used in AppleTalk™
mode.
Pin 20 — TINB1 — Transmit handshake input;
connects to UART’s DTR output.
Pin 21 — N.C. — No Connection.
Pin 22 — TxEN — Transmit data driver enable;
connects to UART’s RTS; transmit data driver
is enabled when this pin is low.
Pin 23 — TINA1 — Transmit data input; connects to UART’s TxD output.
Pin 24 — N.C. — No Connection.
Pin 25 — N.C. — No Connection.
Pin 26 — ROUTA1 — Receive data output:
connects to UART’s RxD input.
Pin 27 — N.C. — No Connection.
Pin 28 — VCC — +5V Power Supply.
FEATURES…
The SP303 is a single chip device that offers
both RS-232 and AppleTalk interfaces. When
configured for RS-232 mode, the SP303 provides 4 drivers and 4 receivers. When the part is
programmed for AppleTalk mode, the SP303
supports Macintosh–type ports. The mode can
be changed at any time by bringing both the SEL
A and the SEL B pins high for Mac mode, or low
for RS-232 mode.
The RS-232 line driver circuits convert TTL–
logic level inputs into inverted RS-232 output
signals. The RS-232 receivers convert the EIA
RS-232 input signals to inverted TTL output
logic levels. The receivers have voltage hysteresis, which helps eliminate spurious output transitions that might result from low–amplitude
noise voltages during slower-speed signal transitions.
When the SP303 is programmed for Mac mode,
the transmit data and receive data signals are
Corporation
SIGNAL PROCESSING EXCELLENCE
to offer more flexible interface capabilities without additional material costs.
SUPPLY
+5V +12V –12V
The SP303 is available in a 28–pin SOIC package for operation over the commercial temperature range.
28
1
15
VCC VDD VEE
TINA1
TINA2
TINB1
TINB2
ROUTA1
ROUTA2
ROUTB1
ROUTB2
23
24
20
19
T1
T2
T3
T4
26 SP303
27
17
16
14
R1
R2
R3
R4
6
5
9
10
3
2
12
TOUTA1
TOUTA2
TOUTB1
TOUTB2
RINA1
APPLICATION EXAMPLE
RS-232 MODE SERIAL INTERFACE
Figure 3 shows the SP303CT used in a dual
serial port application which allows both
RS-232 and Macintosh™ AppleTalk™ Mode
interfaces. With SEL A and SEL B low, the port
can be configured for RS-232. In this mode, the
SP303CT is set up for 4 drivers and 4 receivers.
The transmitter enable pin (pin22) has no effect
in this mode.
RINA2
RINB1
13
RINB2
The RFI filters shown are optional depending
upon the FCC requirements of the system. The
SP303CT has internal slew rate limiting, which
keeps the RS-232 slew rate <30V/µs. Since the
SUPPLY
+5V +12V –12V
GND SELECT
A
B
7
8
28
1
15
VCC VDD VEE
7
SELECT A
Figure 1. RS232 Operating Mode
8
differential, while the handshake-out and handshake-in signals are single–ended. The SP303
does not have the extra GPI (General Purpose
Input). All drivers and receivers can operate at
data rates up to 1 Mbps. The differential driver
used for transmitting data signals is equipped
with a tri-state function. When the TxEN pin is
brought low, the differential driver is enabled;
when it is high, the driver outputs are tri–stated.
The tri–state function does not affect any other
driver in either mode of operation.
One SP303 can significantly reduce the board
space necessary for a similar discrete solution
offering both RS-232 and AppleTalk interfaces.
Due to the space savings, the SP303 can provide
multi-mode interfacing to equipment such as
printers or modems without sacrificing additional board space or cost. This allows the OEM
Corporation
SIGNAL PROCESSING EXCELLENCE
TINA1
TXEN
TINB1
SELECT B
5
23
T1
6
T2
10
ROUTB1
TOUTA1
22
9
20
SP303
ROUTA1
TOUTA2
26
3
12
17
14
2
R1
R2
TOUTB1
TOUTB2
RINA2
RINA1
RINB1
13
GND
Figure 2. Macintosh™ AppleTalk™ Operating Mode
73
SP303CT is usually connected to the outside
world, it is suggested that the user place transient voltage suppression devices on each of the
I/O lines to ensure up to ±25kV ESD protection.
While the part is programmed for RS-232 mode,
the drivers and receivers can operate up to
200kbps. The RS-232 receiver inputs are capable of receiving signals up to ±30V. The
Macintosh™ AppleTalk™ mode inputs and
outputs are protected to guard against the situation where an RS-232 cable is connected to the
port while it is configured for AppleTalk™
mode.
APPLICATION EXAMPLE
MACINTOSH™ APPLETALK™ SERIAL
INTERFACE
Figure 4 shows the SP303CT programmed for
Macintosh™ AppleTalk™ operating mode. In
this mode the SP303CT offers one differential
driver used for transmitting data, one differential receiver used for receiving data, one single–
ended, non–inverting receiver used to receive a
handshake signal, and one single–ended inverting driver used to transmit a handshake signal.
The differential driver used for transmitting
data can be put into tri–state mode by bringing
the TxEN line high; a low on this pin will enable
the driver output. This function only applies to
SUPPLY
+5V +12V –12V
TXD
23
RTS
24
DCD
16
DSR
RXD
CTS
DTR
27
26
17
20
19
28
1
15
VCC VDD VEE
T1
T2
R4
R2
SP303
R1
R3
T3
T4
6
RFI FILTER
5
TXD
RTS
RFI FILTER
13 RFI FILTER
DCD
2
DSR
3
12
9
RFI FILTER
RFI FILTER
RFI FILTER
RFI FILTER
RXD
8
7
5
6
4
2
3
1
CTS
DTR
10
14 GND SELECT
A
B
8
7
SUPPLY
+5V +12V –12V
TXD
23
RTS
24
DCD
16
DSR
RXD
CTS
DTR
27
26
17
20
19
28
1
15
VCC VDD VEE
T1
T2
R4
R2
SP303
R1
R3
T3
T4
6
RFI FILTER
5 RFI FILTER
13 RFI FILTER
2
3
12
9
RFI FILTER
RFI FILTER
RFI FILTER
RFI FILTER
TXD
RTS
DCD
8
DSR
RXD
7
5
6
4
2
3
1
CTS
DTR
10
14 GND SELECT
A
B
8
7
Figure 3. RS-232 Interface.
74
Corporation
SIGNAL PROCESSING EXCELLENCE
the transmit data driver in ApppleTalk™ mode.
Both differential drivers have output signals on
each pin that typically swing ±6V. The peak to
peak differential voltage swing is typically ±12V.
The second driver is used for transmitting the
handshake output signal and can be used as
either a differential driver or single ended. This
particular application required a single–ended
inverting signal for the handshake output signal.
Some Macintosh equipment requires an extra
single–ended inverting receiver which is called
a general purpose input. The GPI receiver is
normally connected to pin 7 on the external 8 pin
connector. This receiver is not available on the
SP303CT.
Since the SP303CT is usually connected to the
outside world, it is suggested that the user place
transient voltage suppression devices on each of
the 1/0 lines to ensure up to ±25kV ESD protection.
POWER SUPPLY SEQUENCING
There are two requirements for power supply
sequencing for the SP303. The first is that VDD
is always greater than VCC. The second is that
when the part is powered up, VDD must be
applied 20ms before VCC.
SUPPLY
+5V +12V –12V
28 1
15
VCC VDDVEE
SELECT A
7
8
RTS
TXD
RXD
SELECT B
22
6
23
5
2
3
26
RFI FILTER
RFI FILTER
RFI FILTER
RFI FILTER
TXDA–
TXDA+
RXDA+
RXDA–
No Connect
SP303
CTS
8
12
13
17
RFI FILTER
7
5
4
2
9
DTR
20
RFI FILTER
6
HSKiA
3
1
HSKoA
10
14 GND
SUPPLY
+5V +12V –12V
28 1
15
VCC VDDVEE
SELECT A
7
8
RTS
TXD
RXD
SELECT B
22
6
23
5
2
3
26
RFI FILTER
RFI FILTER
RFI FILTER
RFI FILTER
TXDA–
TXDA+
RXDA+
RXDA–
No Connect
SP303
CTS
17
8
12
13
RFI FILTER
7
5
4
2
9
DTR
20
RFI FILTER
6
HSKiA
3
1
HSKoA
10
14 GND
Figure 4. Macintosh™ AppleTalk™ Interface.
Corporation
SIGNAL PROCESSING EXCELLENCE
75
ORDERING INFORMATION
Model
Temperature Range
Package
SP303CT ....................................................... 0°C to +70°C ........................................................ 28-pin SOIC
SP303CT/TR ................................................. 0°C to +70°C .................................. 28-pin SOIC/Tape-on-reel
76
Corporation
SIGNAL PROCESSING EXCELLENCE