参考设计
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16-Bit, 8 Channel, Integrated Analog Input module for Programmable Logic Controllers (PLC)
TIDA-00164: This reference design provides a complete solution for a single supply industrial control Analog Input Module. The reference design is suitable for process control end equipment like Programmable Logic Controllers (PLC), Distributed Control system (DCS), Data Acquisition Systems (DAS) modules that must digitize standard industrial current inputs and bipolar or unipolar input voltage ranges up to ±10V. In an industrial environment the analog voltage and current ranges typically include ±2.5 V, ±5 V, ±10 V, 0 V to 5 V, 0 V to 10 V, 4 mA to 20 mA, and 0 mA to 20 mA. This reference design can measure all standard industrial voltage and current inputs. Eight channels are provided on the module and each channel can be configured as a current or voltage input with software configuration. The SAR based architecture of ADS8688 leverages better sampling rate. The ADS8688 also includes an on-chip PGA. The on-chip PGAs are used to provide gain and level shift the bipolar signals. The ISO7141 & ISO1541D provides digital signal isolation between host microcontroller and measurement side. The power isolation has been achieved using LM5017 based Flybuck transformer. The module has on-board EEPROM to store calibration data and module configuration data. This reference design also demonstrate the TI products like hot swap & in-rush current limit controller, isolated Flybuck controller, low noise LDO, and I2C to GPIO expander that can be used in the entire PLC signal processing chain. The module has been designed to be pluggable to the IO Controller (TIDA-00123) for quick testing & evaluation. The module reference design also includes external protection circuit and has been tested and verified to be compliant with IEC61000-4 standards – EFT, ESD and Surge requirements with IO Controller platform.
Adaptive Power Supply for PLC Analog Output Module with Output Channel Protection
TIDA-00231: TIDA-00231 is a reference design for an industrial Programmable Logic Controller (PLC) analog output module. The design provides a unique power saving solution for a digital-to-analog converter (DAC)-based analog current output module with an adaptive power supply. This adaptive power supply dynamically regulates the AVDD supply of the DAC and limits power losses to < 50mW for typical load resistance of > 300Ω. The analog output can source current up to 24mA. This reference design includes the necessary on-board protection circuit and has been tested to IEC61000-4 standard EFT, ESD, and surge requirements with IO Controller platforms. The protection circuitry does not negatively affect the design and Test results showed typical unadjusted errors were less than 0.2% FSR and calibrated accuracy is 0.05%. Watch a TIDA-00231 overview video on the Isolated DC/DC Converter reference design NOW
Temperature Sensor Interface Module for Programmable Logic Controllers (PLC)
TIDA-00018: The TIDA-00018 reference design enables faster development of high precision temperature measurement solutions using 24-Bit delta-sigma ADC and most widely used temperature sensors like thermocouple and RTD. The design guide will address the sensor signal conditioning, thermocouple cold junction compensation, ratiometric measurement technique for RTD, recommended software flow, sensor linearization, sensor diagnostics, transient protection, PCB layout and other practical design considerations for achieving high precision robust design for temperature measurement in industrial applications. The Temperature Sensor Interface Module is a fully isolated design, which is essential for small sensor signal measurement. The heart of this reference design is a 24-Bit delta-sigma ADC that provides a high resolution, high integration, low noise, and low cost complete sensor analog front-end (AFE) for DC sensing applications. This ADC also makes it suitable to interface with different types of sensors, thus saving board space, reducing design efforts, decreasing the time to market, and lower BOM cost. Furthermore, external protection circuitry has been successfully tested for compliance with regulatory IEC61000-4 EFT, ESD, and surge standards. Compliance to IEC61000-4 is necessary to ensure that the design not only survives but also perform as intended in the harsh/noisy industrial environment.
16-Bit Analog Mixed Input and Output Module for Programmable Logic Controller (PLC) Reference Design
TIDA-00170: The TIDA-00170 is a reference design for industrial control Analog Mixed Input Output Modules. The design implements four channel analog input & two channel analog output. The analog input channels can measure all standard industrial voltages up to ±10V and current inputs up to 24mA. The two simultaneous analog outputs can source voltage up to ±10V and current up to 24mA. The reference design includes the necessary on-board protection circuit & is tested for IEC61000-4 standard – EFT, ESD and Surge requirements with IO Controller platform. The protection circuitry does not negatively affect the design and test results showed typical unadjusted errors were less than 0.1% of the full-scale range (FSR) for the analog input channel and less than 0.2% FSR for the analog output channel.
