SN65HVS881 Datasheet, PDF (1/22 Pages) Texas Instruments – INDUSTRIAL 8-DIGITAL-INPUT SERIALIZER WITH DIAGNOSTICS

SN65HVS881
www.ti.com................................................................................................................................................................................................... SLAS642 – MARCH 2009
INDUSTRIAL 8-DIGITAL-INPUT SERIALIZER WITH DIAGNOSTICS
FEATURES
1
•2 Eight Inputs
– High Input Voltage – up to 34 V
– Selectable Debounce Filters – 0 ms to 3 ms
– Flexible Input Current Limit: 0.2 to 5.2 mA
– Field Pins Protected to 15-kV HBM ESD
• Diagnostics:
– Parity Check
– Undervoltage Indication
– Overtemperature Indication
• Output Drivers for External Status LEDs
• Cascadable in Multiples of Eight Inputs
• SPI-Compatible Interface
• Regulated 5-V Output for External Isolator
APPLICATIONS
• Sensor Inputs for Industrial Automation and
Process Control
• High Channel Count Digital Input Modules for
PC and PLC Systems
• Decentralized I/O Modules
• Motion Control Systems
DESCRIPTION
The SN65HVS881 is an eight channel, digital-input serializer for high-channel density digital input modules in
industrial automation. In combination with galvanic isolators the device completes the interface between the high
voltage signals on the field-side and the low-voltage signals on the controller side. Input signals are
current-limited and then validated by internal debounce filters.
With the addition of a few external components, the input switching characteristics can be configured in
accordance with IEC61131-2 for Type 1, 2 and 3 sensor switches.
Upon the application of load and clock signals, input data is latched in parallel into the shift register and
afterwards clocked out serially.
Cascading of multiple devices is possible by connecting the serial output of the leading device with the serial
input of the following device, enabling the design of high-channel count input modules. Multiple devices can be
cascaded through a single serial port, reducing both the isolation channels and controller inputs required.
Input status can be visually indicated via constant current LED outputs. The current limit on the inputs is set by a
single external precision resistor. An integrated voltage regulator provides a 5V output to supply low-power
isolators. An on-chip temperature sensor provides diagnostic information for graceful shutdown and system
safety. An internal parity check for odd parity ensures trustworthy transmission of serial data to the system
controller.
The SN65HVS881 is available in a 28-pin PWP PowerPAD™ package, allowing for efficient heat dissipation. The
device is characterized for operation at temperatures from –40°C to 125°C
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PowerPAD is a trademark of Texas Instruments.
2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2009, Texas Instruments Incorporated