SP339E
RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION
DECEMBER 2013
REV. 1.0.4
FEATURES
GENERAL DESCRIPTION
x Pin selectable Cable Termination
The SP339 is an advanced multiprotocol transceiver
supporting RS-232, RS-485, and RS-422 serial
standards in a 40 pin QFN package. Integrated cable
termination and four 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.
x No external resistors required for RS-485/422
termination and biasing
x 3.3V or 5V Single Supply Operation
x Robust ESD Protection on bus pins
■ ±15kV IEC 61000-4-2 (Air Gap)
■ ± 8kV IEC 61000-4-2 (Contact)
■ ±15kV Human Body Model (HBM)
The RS-485/422 modes feature one driver and one
receiver (1TX/1RX) in both half and full duplex
configurations. The RS-232 mode (3TX/5RX)
provides full support of all eight signals commonly
used with the DB9 RS-232 connector. A dedicated
diagnostic loopback mode is also provided.
x Max Data Rate of 20Mbps in RS-485/422 Modesꢀ
and up to 1Mbps in RS-232 Modes
x Pin selectable 250kbps Slew Limiting
x 3 Drivers, 5 Receivers RS-232/V.28
x 1 Driver, 1 Receiver RS-485/422
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).
■ Full and Half Duplex Configuration
■ 1/8th Unit Load, up to 256 receivers on bus
All transmitter outputs and receiver inputs feature
robust electrostatic discharge (ESD) protection toꢀ
15kV IEC-61000-4-2 Air Gap, 8kV IEC-61000-4-2
Contact, and 15kV Human Body Model (HBM).
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.
x RS-485/422 Enhanced Failsafe for open, shorted,
or terminated but idle inputs
x Space saving 6mm x 6mm QFN-40 Package
x Pin compatible with SP338E
TYPICAL APPLICATIONS
x Dual Protocol Serial Ports (RS-232 or RS-485/422)
x Industrial Computers
The RS-232 receiver inputs include a 5k: pull-down
to ground. The RS-485/422 receiver inputs are high
impedance (>96k: when termination is disabled),
allowing up to 256 devices on a single communication
bus (1/8th unit load).
x Industrial and Process Control Equipment
x Point-Of-Sale Equipment
The SP339 operates from a single power supply,
either 3.3V or 5V, with low idle current (2mA typical in
all modes). The shutdown mode consumes less than
10µA for low power standby operation.
x Networking Equipment
x HVAC Controls Equipment
x Building Security and Automation Equipment
ORDERING INFORMATION
PART NUMBER
SP339EER1-L
PACKAGE
40-pin QFN
40-pin QFN
40-pin QFN
40-pin QFN
OPERATING TEMPERATURE RANGE
-40°C to +85°C
DEVICE STATUS
Active
SP339EER1-L/TR
SP339ECR1-L
-40°C to +85°C
Active
0°C to +70°C
Active
SP339ECR1-L/TR
0°C to +70°C
Active
NOTE: -L = Green / RoHS Compliant, /TR = Tape and Reel
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com