TIDUFI7
May 2026
1
Description
Resources
Features
Applications
6
1
System Description
1.1
Key System Specifications
2
System Overview
2.1
Block Diagram
2.2
Design Considerations
2.3
Highlighted Products
2.3.1
ADS125H18
2.3.2
MSPM0G5117
2.3.3
TXE8116
2.3.4
ISO6441
2.3.5
LM5180
2.3.6
UCC33420
2.3.7
TPS7A2050
2.3.8
TLV709A33
3
System Design Theory
3.1
Power Supply
3.1.1
24V Input Power Path
3.1.2
USB Power Path
3.1.3
Non-isolated MCU Power
3.1.4
Isolated ADC and Peripheral Power
3.2
Analog Input Ports
3.2.1
Analog Input Port and Protection
3.2.2
Voltage and Current Mode Selection
3.2.3
Current Measurement Path
3.2.4
Voltage Measurement Path
3.2.5
Channel Configuration
3.3
Digital Control and Data Acquisition Subsystem
3.3.1
Microcontroller Platform
3.3.2
Precision ADC
3.3.3
Shared SPI Bus and Chip-Select Forwarding
3.3.4
I/O Expander
3.3.5
Optional External Reference
4
Hardware, Software, Testing Requirements, and Test Results
4.1
Hardware Requirements
4.1.1
PCB Overview
4.1.2
Connector Description
4.1.2.1
Power Connectors
4.1.2.2
Input Connectors
4.2
Test Setup and Test Results
4.2.1
ADS125H18 General Configuration
4.2.2
Offset Test
4.2.2.1
Test Setup
4.2.2.2
Test Results
4.2.2.2.1
Voltage Input Mode
4.2.2.2.2
Current Input Mode
4.2.3
System Accuracy Error and Noise Performance Test
4.2.3.1
Calculation Method
4.2.3.2
Test Setup
4.2.3.3
Test Results
4.2.3.3.1
Voltage Input Mode
4.2.3.3.2
Current Input Mode
4.2.4
Input Protection Test
4.2.4.1
Test Setup
4.2.4.2
Test Results
5
Design and Documentation Support
5.1
Design Files
5.1.1
Schematics
5.1.2
BOM
5.1.3
PCB Layout Recommendations
5.1.3.1
Layout Prints
5.2
Tools and Software
5.2.1
Tools
5.2.2
Software
5.3
Documentation Support
5.4
Support Resources
Trademarks
6
Revision History
7
About the Author
Design Guide
Eight-Channel V and I Combined Analog Input Module with Single Supply Reference Design