8-ch isolated high voltage analog input module reference design

The TIDA-00764 reference design is a high voltage analog input module with eight channels. Each channel can be used for both, voltage and current measurement. The TI Design uses the 16-bit analog-to-digital converter (ADC) ADS8681 that can handle input voltage of up to ±12.288V. This make any preprocessing of standard input voltages in the industrial space unnecessary. In addition, four channels of the design are able to handle common-mode (CM) voltages of up to ±160V. Therefore, the user does not need to worry about ground loops or compensation currents flowing between the connected inputs.

Features:

• High voltage inputs of up to ±12.288V
• Voltage and current measurement for every channel
• 4 channels with common-mode of up to ±160V
• -85dB crosstalk rejection for adjacent channels
• 100MOhm input impedance
• Surge transient immunity according to EN 61000-4-5 class 2 (±1kV, 24A)

Parts Include:
ADS8681      16-bit, 1 MSPS, 5V SAR ADC with Integrated Analog Front End & Bipolar Inputs 
INA149      High Common Mode Voltage Difference Amplifier 
ISO7140CC      4242-VPK Small-Footprint and Low-Power 4/0 Quad Channel Digital Isolator with Noise Filter 
ISO7141CC      4242-VPK Small-Footprint and Low-Power 3/1 Quad Channel Digital Isolator with Noise Filter 
LP2985-50      Single Output LDO, 150mA, Fixed(5.0V), 1.5% Tolerance, Low Quiescent Current, Low Noise 
MUX36S08      MUX36xxx 36-V, Low-Capacitance, Low-Leakage-Current, Precision, Analog Multiplexers 
OPA192      High-Voltage, Rail-to-Rail Input/Output, 5µV, 0.2µV/˚C, Precision Operational Amplifier 
SN74AHC594      8-Bit Shift Registers With Output Registers 
SN74LVC1G332      Single 3-Input Positive-OR Gate 
SN74LVC2G86      Dual 2-Input Exclusive-Or Gate 
TPS55010      2.95V To 6V Input, 2W, Isolated DC/DC Converter with Integrated FETS 
TS5A23157      Dual 10-Ohm SPDT Analog Switch

Learn more by downloading the reference design below