Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com
SP330E
RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
November 2013 Rev. 1.0.0
GENERAL DESCRIPTION
The SP330 is an advanced multiprotocol transceiver
supporting RS-232, RS-485, and RS-422 serial
standards and featuring a variable low voltage logic
interface, down to 1.65V. Full operation requires only
four external charge pump capacitors.
The RS-485/RS-232 mode pin selects RS-485 mode
when high, and RS-232 mode when low. In RS-485
mode the HALF/FULL pin configures the transceiver
as either half or full duplex.
The high speed drivers operate up to 20Mbps in RS-
485/422 modes, and up to 1Mbps in RS-232 mode.
All drivers can be slew limited to 250kbps in any
mode to minimize electromagnetic interference (EMI)
by setting the dedicated SLEW pin low.
All transmitter outputs and receiver inputs feature
robust electrostatic discharge (ESD) protection to
±15kV IEC 61000-4-2 Airgap, ±15kV Human Body
Model (HBM) and ±8kV IEC 61000-4-2 Contact. Each
receiver output has full fail-safe protection to avoid
system lockup, oscillation, or indeterminate states by
defaulting to logic-high output level when the inputs
are open, shorted, or terminated but undriven. No
external biasing resistors are required.
The RS-232 receiver inputs include a 5k pull-down
to ground when in RS-232 mode. The RS-485/422
receiver inputs are high impedance (>96k), allowing
up to 256 devices on a single communication bus
(1/8th unit load).
The SP330 operates from a single power supply,
either 3.3V or 5V, with low idle current. The shutdown
mode consumes less than 1µA in low power standby
operation with RS-232 receivers enabled.
FEATURES
Robust ESD Protection:
■±15kV IEC 61000-4-2 Air Gap Discharge
■± 8kV IEC 61000-4-2 Contact Discharge
■±15kV Human Body Model (HBM)
20Mbps RS-485 and 1Mbps RS-232 Data Rates
Pin-Selectable 250kbps Slew Limiting
Single Supply Operation from +3V to +5.5V
1.65V to 5.5V Logic Interface VL pin
2 Drivers, 2 Receivers RS-232/V.28
1 Driver, 1 Receiver RS-485/422
■Full or Half Duplex Configuration
■1/8th Unit Load, up to 256 receivers on bus
RS-485/422 Enhanced Receiver Fail-safe for open,
shorted, or terminated but idle inputs
10nA Shutdown Supply Current (typical)
Small 24 TSSOP package
TYPICAL APPLICATIONS
Software Programmable Serial Ports
(RS-232, RS-422, RS-485)
Industrial and Single Board Computers
Industrial and Process Control Equipment
Point-Of-Sale Equipment
HVAC Controls and Networking Equipment
Building Security and Automation
ORDERING INFORMATION
PART NUMBER PACKAGE OPERATING TEMPERATURE RANGE DEVICE STATUS
SP330EEY-L 24-pin TSSOP -40°C to +85°C Active
SP330EEY-L/TR 24-pin TSSOP -40°C to +85°C Active
NOTE: SP330EEY-L and SP330EEY-L/TR are Green / RoHS Compliant
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
CAUTION:
ESD (ElectroStatic Discharge) sensitive device. Permanent damage may occur on unconnected devices
subject to high energy electrostatic fields. Unused devices must be stored in conductive foam or shunts.
Personnel should be properly grounded prior to handling this device. The protective foam should be
discharged to the destination socket before devices are removed.
ESD PROTECTION
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 to 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.
Supply Voltage VCC -0.3V to +6.0V
Logic Interface Voltage VL VL VCC
Voltage at TTL Input Pins -0.3V to +6.0V
Receiver Input Voltage (from Ground) ±18V
Driver Output Voltage (from Ground) ±18V
Short Circuit Duration, TX out to Ground Continuous
Storage Temperature Range -65°C to +150°C
Lead Temperature (soldering, 10s) +300°C
Power Dissipation 24-pin TSSOP
(derate 26.0mW/°C above +70°C) 900mW
MIN. TYP. MAX. UNITS
TX Output & RX Input Pins
±15 kV IEC 61000-4-2 Airgap
± 8 kV IEC 61000-4-2 Contact
±15 kV Human Body Model (HBM)
All Other Pins ± 3 kV Human Body Model (HBM)
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
ELECTRICAL CHARACTERISTICS
UNLESS OTHERWISE NOTED:
VCC = +3.0V to +5.5V, C1-C4 = 0.1µF; TA = TMIN to TMAX. Typical values are at VL = VCC = 3.3V, TA = +25°C.
SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
DC CHARACTERISTICS
ICC Supply Current (RS-232) 12.5 mA No load, Idle inputs,
RS-485/RS-232 = 0V
ICC Supply Current (RS-485/422) 1.8 4.5 mA No load, Idle inputs,
RS-485/RS-232 = VCC
ICC Vcc Shutdown Current 0.01 1µASHDN = 0V, Receiver inputs
open or grounded
TRANSMITTER and LOGIC INPUTS (PINS 11 - 14 & 18 - 20)
VIL Logic Input Voltage Low VL
3 V
VIH Logic Input Voltage High 2VL
3 V
IINL Logic Input Leakage Current ±0.01 ±1 µA
IINPD Logic Input Pulldown Current 10 50 µARE pin 18, VIN = VL
VHYS Logic Input Hysteresis 200 mV
RS-232 and RS-485/422 RECEIVER OUTPUTS (PINS 8 & 9)
VOL Receiver Output Voltage Low 0.4 VIOUT = 1.5mA
VOH Receiver Output Voltage High VL-0.6 VIOUT = -1.5mA
IOSS Receiver Output Short Circuit Current ±20 ±85 mA 0 VO VL
IOZ Receiver Output Leakage Current ±0.05 ±1 µA0 VO VL,
Receivers disabled
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
ELECTRICAL CHARACTERISTICS (Continued)
UNLESS OTHERWISE NOTED:
VCC = +3.0V to +5.5V, C1-C4 = 0.1µF; TA = TMIN to TMAX. Typical values are at VCC = 3.3V, TA = +25°C.
SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
RS-232 SINGLE-ENDED RECEIVER INPUTS (PINS 16 & 17)
VIN Input Voltage Range -15 +15 V
VIL Input Threshold Low
0.6 1.2 VVCC = 3.3V
0.8 1.5 VVCC = 5.0V
VIH Input Threshold High
1.5 2.0 VVCC = 3.3V
1.8 2.4 VVCC = 5.0V
VHYS Input Hysteresis 0.5 V
RIN Input Resistance 357k-15V VIN +15V
RS-232 SINGLE-ENDED TRANSMITTER OUTPUTS (PINS 6 & 7)
VOUT Output Voltage Swing ±5.0 ±5.5 VOutputs loaded with 3k to Gnd
ROFF Output Power Off Impedance 300 10M VCC = 0V, VOUT = ±2V
ISC Output Short Circuit Current ±30 ±60 mA VOUT = 0V
IOOutput Leakage Current ±125 µASHDN = 0V, VOUT = ±9V,
VCC = 0V or 5.5V
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
ELECTRICAL CHARACTERISTICS (Continued)
UNLESS OTHERWISE NOTED:
VCC = +3.0V to +5.5V, C1-C4 = 0.1µF; TA = TMIN to TMAX. Typical values are at VCC = 3.3V, TA = +25°C.
SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
RS-485/422 DIFFERENTIAL RECEIVER INPUTS (A,B)
RIN Receiver Input Resistance 96 k-7V VCM +12V
IIN Receiver Input Current
125 µAVIN = +12V
-100 µAVIN = -7V
VTH
Receiver Differential
Threshold Voltage -200 -125 -50 mV -7V VCM +12V
VTH Receiver Input Hysteresis 25 mV
RS-485/422 DIFFERENTIAL DRIVER OUTPUTS (Y, Z)
VOD Differential Driver Output
1.5 VCC VRL = 54 (RS-485), Figure 4
1.5 VCC V-7V VCM +12V, Figure 5
2VCC VRL = 100 (RS-422), Figure 4
VODChange In Magnitude of
Differential Output Voltage 0.2 VRL = 54 or 100, Figure 4
VCM Driver Common Mode Output Voltage 3 V RL = 54 or 100, Figure 4
VCMChange In Magnitude of
Common Mode Output Voltage 0.2 VRL = 54 or 100, Figure 4
IOSD Driver Output Short Circuit Current ±250 mA -7V VY or VZ +12V, Figure 6
IODriver Output Leakage Current ±125 µA
DE = 0V or SHDN = 0V,
VY or VZ = -7V or +12V,
VCC = 0V or 5.5V
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
TIMING CHARACTERISTICS
UNLESS OTHERWISE NOTED:
VCC = +3.0V to +5.5V, C1-C4 = 0.1µF; TA = TMIN to TMAX. Typical values are at VCC = 3.3V, TA = +25°C.
SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
ALL MODES
tENABLE Enable from Shutdown 1000 ns
tSHUTDOWN Enable to Shutdown 1000 ns
RS-232, DATA RATE = 250kbps (SLEW = 0V), ONE TRANSMITTER SWITCHING
Maximum Data Rate 250 kbps RL = 3k, CL = 1000pF
tRHL, tRLH Receiver Propagation Delay 100 ns
CL = 150pF, Figure 7
tRHL-tRLHReceiver Propagation Delay Skew 100 ns
tDHL, tDLH Driver Propagation Delay 1400 ns RL = 3k, CL = 2500pF,
Figure 8
tDHL-tDLHDriver Propagation Delay Skew 600 ns
tSHL, tSLH Transition Region Slew Rate from
+3.0V to -3.0V or -3.0V to +3.0V 630 V/µs
VCC = +3.3V, RL = 3k to 7k,
CL = 150pF to 2500pF,
TA = 25°C, Figure 8
tSHL, tSLH Transition Region Slew Rate from
+3.0V to -3.0V or -3.0V to +3.0V 430 V/µs
VCC = +3.3V, RL = 3k to 7k,
CL = 150pF to 2500pF,
Figure 8
RS-232, DATA RATE = 1Mbps (SLEW = VCC), ONE TRANSMITTER SWITCHING
Maximum Data Rate 1Mbps RL = 3k, CL = 250pF
tRHL, tRLH Receiver Propagation Delay 100 ns
CL = 150pF, Figure 7
tRHL-tRLHReceiver Propagation Delay Skew 100 ns
tDHL, tDLH Driver Propagation Delay 300 ns RL = 3k, CL = 1000pF,
Figure 8
tDHL-tDLHDriver Propagation Delay Skew 150 ns
tSHL, tSLH Transition Region Slew Rate from
+3.0V to -3.0V or -3.0V to +3.0V 13 150 V/µs
VCC = +3.3V, RL = 3k to 7k,
CL = 150pF to 1000pF,
Figure 8
tSHL, tSLH Transition Region Slew Rate from
+3.0V to -3.0V or -3.0V to +3.0V 24 150 V/µs
VCC = +3.3V, RL = 3k to 7k,
CL = 150pF to 1000pF,
TA = 25°C, Figure 8
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
TIMING CHARACTERISTICS (Continued)
UNLESS OTHERWISE NOTED:
VCC = +3.0V to +5.5V, C1-C4 = 0.1µF; TA = TMIN to TMAX. Typical values are at VCC = 3.3V, TA = +25°C.
SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
RS-485/RS-422, DATA RATE = 250kbps (SLEW = 0V), ONE TRANSMITTER SWITCHING
Maximum Data Rate 250 kbps RL = 54, CL = 50pF
tRPHL, tRPLH Receiver Propagation Delay 50 150 ns
CL = 15pF, Figure 9
tRPHL-tRPLHReceiver Propagation Delay Skew 10 ns
tDPHL, tDPLH Driver Propagation Delay 500 1000 ns
RL = 54, CL = 50pF,
Figure 10
tDPHL-tDPLHDriver Propagation Delay Skew 100 ns
tDR, tDF Driver Rise and Fall Time 300 650 1200 ns
tRZH, tRZL Receiver Output Enable Time 200 ns
CL = 15pF, Figure 11
tRHZ, tRLZ Receiver Output Disable Time 200 ns
tDZH, tDZL Driver Output Enable Time 1000 ns RL = 500, CL = 50pF,
Figure 12
tDHZ, tDLZ Driver Output Disable Time 200 ns
RS-485/RS-422, DATA RATE = 20Mbps (SLEW = VCC), ONE TRANSMITTER SWITCHING
Maximum Data Rate 20 Mbps RL = 54, CL = 50pF
tRPHL, tRPLH Receiver Propagation Delay 50 150 ns
CL = 15pF, Figure 9
tRPHL-tRPLHReceiver Propagation Delay Skew 10 ns
tDPHL, tDPLH Driver Propagation Delay 30 100 ns
RL = 54, CL = 50pF,
Figure 10
tDPHL-tDPLHDriver Propagation Delay Skew 10 ns
tDR, tDF Driver Rise and Fall Time 10 20 ns
tRZH, tRZL Receiver Output Enable Time 200 ns
CL = 15pF, Figure 11
tRHZ, tRLZ Receiver Output Disable Time 200 ns
tDZH, tDZL Driver Output Enable Time 200 ns RL = 500, CL = 50pF,
Figure 12
tDHZ, tDLZ Driver Output Disable Time 200 ns
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
PIN DESCRIPTIONS
Pin Name RS-232 RS-485 Full Duplex RS-485 Half Duplex
1C1+ Charge pump cap 1 positive lead, 0.1µF
2VL Logic Supply for TTL Inputs and Outputs, VL = +1.65V to +5.5V or tie to VCC
3VCC Main Supply, VCC = +3.0V to +5.5V, bypass to ground with 1.0µF
4C1- Charge pump cap 1 negative lead
5GND Ground
6T1OUT, B/Z Transmitter 1 Output Z Driver Neg Output B/Z Neg Input/Output
7T2OUT, A/Y Transmitter 2 Output Y Driver Pos Output A/Y Pos Input/Output
8R1OUT Receiver 1 Output X X
9R2OUT, RO Receiver 2 Output Receiver TTL Output Receiver TTL Output
10
11 SHDN Low power shutdown mode when low
12 SLEW Data rate limited to 250kbps when low
13 RS-485/RS-232 0 1 1
14 HALF/FULL X 0 1
15 GND Ground
16 R2IN, A Receiver 2 Input A Pos Receiver Input X
17 R1IN, B Receiver 1 Input B Neg Receiver Input X
18 RE XReceiver enabled when low
19 T2IN, DE Transmitter 2 Input Driver enabled when high
20 T1IN, DI Transmitter 1 Input Driver TTL Input
21 V- Charge pump negative supply, 0.1µF from ground
22 C2- Charge pump cap 2 negative lead
23 C2+ Charge pump cap 2 positive lead, 0.1µF
24 V+ Charge pump positive supply, 0.1µF to ground
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
SUGGESTED DB9 CONNECTOR PINOUT
DB9
Pin RS-232 RS-485
Full Duplex
RS-485
Half Duplex
1
2RXD RX+
3TXD TX- Data-
4
5Ground
6
7RTS TX+ Data+
8CTS RX-
9
SP330E
10
RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
BLOCK DIAGRAMS
FIGURE 1. RS-232 MODE
Pin 18 has a 300k internal pull-down (not shown).
T1OUT
T2OUT
R1OUT
R2OUT
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
C2
0.1µF
C3
0.1µF
Cc
1.0µF
T2
R1
R2
T1
C4
0.1µF
C1
0.1µF
C1+
V
L
V
CC
C1-
GND
_____
SHDN
_____
SLEW
V+
C2+
C2-
V-
GND
______
RS-485/RS-232
T1IN
T2IN
R1IN
R2IN
SP330
24 pin TSSOP
RS-232
5k
5k
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
FIGURE 2. RS-485 FULL DUPLEX MODE
Pin 18 has a 300k internal pull-down (not shown).
V+
C2+
C2-
V-
GND
____
HALF/FULL
______
RS-485/RS-232
Z
Y
RO
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
C2
0.1µF
C3
0.1µF
Cc
1.0µF
C4
0.1µF
C1
0.1µF
C1+
V
L
V
CC
C1-
GND
_____
SHDN
_____
SLEW
DI
DE
__
RE
B
A
SP330
24 pin TSSOP
RS-485 Full Duplex
R
D
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
FIGURE 3. RS-485 HALF DUPLEX MODE
Pin 18 has a 300k internal pull-down (not shown).
V+
C2+
C2-
V-
GND
____
HALF/FULL
______
RS-485/RS-232
B/Z
A/Y
RO
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
C2
0.1µF
C3
0.1µF
Cc
1.0µF
C4
0.1µF
C1
0.1µF
C1+
V
L
V
CC
C1-
GND
_____
SHDN
_____
SLEW
DI
DE
__
RE
SP330
24 pin TSSOP
RS-485 Half Duplex
R
D
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
TEST CIRCUITS
FIGURE 4. RS-485/422 DIFFERENTIAL DRIVER OUTPUT VOLTAGE
FIGURE 5. RS-485/422 DIFFERENTIAL DRIVER OUTPUT VOLTAGE OVER COMMON MODE
FIGURE 6. RS-485/422 DRIVER OUTPUT SHORT CIRCUIT CURRENT
DVOD VCM
DE = VL
DI=0VorV
L
Z
Y
R
L
2
R
L
2
DVOD VCM
60
375
375
Z
Y
DE = VL
DI=0VorV
L
D
-7V to +12V V
Z
Y
IOSD
DE = 0V or VL
DI=0VorV
L
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
FIGURE 7. RS-232 RECEIVER PROPAGATION DELAY
FIGURE 8. RS-232 DRIVER PROPAGATION DELAY
C
L
Rx
VIN VOUT
+3V
-3V
VOH
VOL
t
RHL
t
RLH
V
IN
V
OUT
1.5V 1.5V
V
L
2
V
L
2
R
L
C
L
Tx
VIN VOUT
VL
0V
+3V
-3V t
SHL
t
SLH
V
IN
V
OUT
t
DHL
0V 0V
t
DLH
V
L
2
V
L
2
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
FIGURE 9. RS-485/422 RECEIVER PROPAGATION DELAY
FIGURE 10. RS-485/422 DRIVER PROPAGATION DELAY AND RISE/FALL TIMES
C
L
B
A
R
RE = 0V
RO
B
A
RO
t
RPLH
t
RPHL
+1V
0V
-1V
VOH
VOL
V
L
2
V
L
2
DVOD R
L
C
L
Z
Y
DE = VL
DI
VL
0V
Z
Y
VOD+
0V
VOD-
V
OD
90%
10%
90%
10%
t
DR
t
DF
t
DPLH
t
DPHL
DI
V
OD
(VY-V
Z)
tSKEW =|t
DPHL ڏtDPLH|
V
L
2
V
L
2
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
FIGURE 11. RS-485/422 RECEIVER OUTPUT ENABLE/DISABLE TIMES
R
L
C
L
RO
B
A
R
RE
VL
0V
VOH
0V
V
OH
2
V
OH
-0.25V
t
RZH
t
RHZ
RE
V
A
=V
CC
V
B
=0V
RO
V
L
2
V
L
2
CL
RO
B
A
R
RE
RL
V
L
VL
0V
VL
VOL
V
L
+V
OL
2V
OL
+0.25V
t
RZL
t
RLZ
RE
V
A
=0V
V
B
=V
CC
RO
V
L
2
V
L
2
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
FIGURE 12. RS-485/422 DRIVER OUTPUT ENABLE/DISABLE TIMES
R
L
C
L
D
TestingZ:DI=0V
TestingY:DI=V
L
DE
Z
Y
V
OUT
VL
0V
VOH
VOL
DE
V
OUT
V
OH
+V
OL
2
V
OH
-0.25V
t
DZH
t
DHZ
V
L
2
V
L
2
RL
CL
D
DE
V
CC
Z
Y
V
OUT
TestingZ:DI=V
L
TestingY:DI=0V
VL
0V
VOH
VOL
t
DZL
t
DLZ
DE
V
OUT
V
OH
+V
OL
2V
OL
+0.25V
V
L
2
V
L
2
SP330E
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RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
PRODUCT SUMMARY
The SP330 is an advanced multiprotocol transceiver supporting RS-232, RS-485, and RS-422 serial
standards. The multiple configuration modes allow all three protocols to be used interchangeably over a single
cable or connector with no additional switching components. Full operation requires only four external charge
pump capacitors.
ENHANCED FAILSAFE
The enhanced failsafe feature of the SP330 guarantees a logic-high receiver output when the receiver inputs
are open, shorted, or terminated but idle/undriven. The enhanced failsafe interprets 0V differential as a logic
high with a minimum 50mV noise margin, while maintaining compliance with the EIA/TIA-485 standard of
±200mV. No external biasing resistors are required, further easing the usage of multiple protocols over a single
connector.
±15kV ESD PROTECTION
ESD protection structures are incorporated on all pins to protect against electrostatic discharges encountered
during handling and assembly. The bus pins (driver outputs and receiver inputs) have extra protection
structures, which have been tested up to ±15kV without damage. These structures withstand high ESD in all
states: normal operation, in shutdown, and when powered off.
ESD protection is be tested in various ways. Exar uses the following methods to qualify the protection
structures designed into SP330:
±8kV using IEC 61000-4-2 Contact Discharge
±15kV using IEC 61000-4-2 Airgap Discharge
±15kV using the Human Body Model (HBM)
The IEC 61000-4-2 standard is more rigorous than HBM, resulting in lower voltage levels compared with HBM
for the same level of ESD protection. Because IEC 61000-4-2 specifies a lower series resistance, the peak
current is higher than HBM. The SP330 has passed both HBM and IEC 61000-4-2 testing without damage.
VARIABLE LOGIC LEVEL VOLTAGE
The SP330 includes a VL pin which reduces the logic level thresholds to interface with processors operating at
reduced supply voltages. This pin should be connected to the supply voltage of the processor or UART block,
or can be connected to VCC for typical logic levels.
SP330E
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REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
TRUTH TABLES
TABLE 1: RS-232 TX TRUTH TABLE
INPUTS OUTPUTS
SHDN RS-485/RS-232 DI/T1IN, DE/T2IN Z(B)/T1OUT, Y(A)/T2OUT
0 X X 1/8th unit load
1 0 0 1
1 0 1 0
1 1 X RS-485 Mode
TABLE 2: RS-232 RX TRUTH TABLE
INPUTS OUTPUTS
SHDN RS-485/RS-232 B/R1IN, A/R2IN R1OUT, RO/R2OUT
X 0 0 1
X 0 1 0
X 0 Inputs open 1
X 1 X R1OUT High-Z,
RO/R2OUT in RS-485 Mode
SP330E
20
RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
TABLE 3: RS-485/422 TX TRUTH TABLE
INPUTS OUTPUTS
SHDN RS-485/RS-232 DE/T2IN DI/T1IN Z(B)/T1OUT Y(A)/T2OUT
0 X X X 1/8th unit load 1/8th unit load
1 1 0 X 1/8th unit load 1/8th unit load
111010
111101
X 0 X X RS-232 Mode
TABLE 4: RS-485/422 RX TRUTH TABLE
INPUTS OUTPUT
RS-485/RS-232 SHDN HALF/FULL RE (A-B) (Y-Z) RO/R2OUT
1 0 X X X X High-Z
1 1 0 0 -50mV X 1
1 1 0 0 -200mV X 0
1 1 0 0 Floating X 1
1 1 1 0 X -50mV 1
1 1 1 0 X -200mV 0
1 1 1 0 X Floating 1
1 1 X 1 X X High-Z
0 X X X X X RS-232 Mode
SP330E
21
REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
PACKAGE DRAWINGS
FIGURE 13. TSSOP 24 DRAWING
ECN 1347-07 11/19/2013
SP330E
22
RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE REV. 1.0.0
FIGURE 14. TSSOP 24 DIMENSIONS
23
NOTICE
EXAR Corporation reserves the right to make changes to the products contained in this publication in order to
improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any
circuits described herein, conveys no license under any patent or other right, and makes no representation that
the circuits are free of patent infringement. Charts and schedules contained here in are only for illustration
purposes and may vary depending upon a user’s specific application. While the information in this publication
has been carefully checked; no responsibility, however, is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where the
failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to
significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless
EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has
been minimized; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately
protected under the circumstances.
Copyright 2013 EXAR Corporation
Datasheet November 2013.
For technical support please email Exar’s Serial Technical Support group at: serialtechsupport@exar.com.
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.
SP330E
REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH 1.65V-5.5V INTERFACE
REVISION HISTORY
DATE REVISION DESCRIPTION
Nov 2013 1.0.0 Production Release
