Simplify high-voltage design with a fully integrated device driven by a single 5V power supply.

TI Korea (CEO Kent Chon, www.ti.com/ww/kr ) October 15, 2014 – TI (CEO Kent Chon) announced the addition of the first new product in its high-voltage family to its successive approximation register (SAR) analog-to-digital converter (ADC) portfolio. The 8-channel ADS8688 and 4-channel ADS8684 support an input range of up to ±10.24V and can simplify system power requirements by operating from a single 5V power supply. By providing the industry's lowest gain drift, offset voltage and offset drift, and the best precision reference, these products enable engineers to achieve unprecedented accuracy over an extended industrial temperature range during design.

This new ADC family improves overall system accuracy when designing various multi-channel industrial applications, such as power automation, low- and medium-voltage relay protection, protection relay monitoring, factory automation equipment, and Programmable Logic Controllers (PLCs). (For more information on the ADS8688 family, please refer to www.ti.com/ADS8688-pr-kr )

Key Features of the ADS8688 Product Family
• No high-voltage power supply required: System design is simplified as there is no need to supply a separate high-voltage power supply. These devices support a bipolar input range of ±10.24V and a unipolar range of ±10.24V using a single 5V power supply.
• Excellent DC Error Performance: With excellent DC error specifications, it achieves over 99.9% accuracy without calibration, enabling system-level performance. These devices provide a gain drift of 4 ppm/°C and an offset drift of 3 ppm/°C, so designers do not need to waste time on system calibration for temperature ranges.
• Superior performance across the entire temperature range: Improved low-temperature drift specifications through an integrated precision reference and reference buffer, eliminating the need for external circuitry and achieving precise performance over an extended industrial temperature range of -40°C to 125°C.
• Integration of multiple functions for industrial sensor design: These devices integrate 20 active components, including a Programmable Gain Amplifier, driver amplifier, multiplexer, voltage reference, reference buffer, and SAR ADC, into a single chip, and additionally provide auxiliary channel inputs that can interface directly with the ADC. With the integration of these components, the ADS8688 and ADS8684 can be directly connected to various types of sensors that do not require signal conditioning.

Tools and support to get started with design
TI provides various support tools, including simulation models, hardware evaluation kits, and reference designs, to help developers shorten time-to-market when designing with the ADS8688.

System developers can rapidly evaluate the ADS8688 and ADS8684 in as little time as evaluating other precision ADCs using a new, easy-to-install Performance Demo Kit (PDK). This PDK includes an evaluation module and a simple capture card and operates plug-and-play, allowing for simple installation with just one click instead of online software installation. Through this kit's intuitive and easy-to-use GUI (Graphical User Interface), the performance of the ADC can be quickly evaluated in specific finished products.

In addition, TI Designs provides theories, simulations, calculations, design methodologies, etc. through the following reference designs:
• Phase-corrected 8-channel multiplexed data acquisition system for power automation (TIPD167)
• 16-bit 8-channel integrated analog input module for PLC (TIDA_00164)

With support for engineers, you can find solutions and post questions on the Precision Data Converters Forum of the TI E2E™ community, and get help from fellow engineers and TI experts to solve problems.

Package, supply, price
The ADS8688 family is available in a 38-pin 9.7mm x 4.4mm TSSOP package. The following 16-bit products are currently available, and 12-bit and 14-bit products are scheduled to be supplied in 2015.

Device Resolution, Speed, Number of Channels, Price per Unit (when quantity is 1,000)
ADS8688
16bit 500kSPS 8 11 dollars
ADS8684
16bit 500kSPS 4 8 dollars

More detailed information on TI's data converter portfolio:
• ADS8688 Datasheet
• Purchase ADS8688EVM-PDK from the TI eStore
• Analog Wire Blog: The Impact of Input Signals on SAR ADC Selection
• The Precision Hub Blog: Factors Affecting the Overall Accuracy of ADCs
• SAR AVideo on how to achieve the DC datasheet specifications
• Optimization of front-end signal conditioning circuits in software simulation is possible by using IBIS and TINA-TI™ models.