Project Description

4 CH ADC and 2 NPN digital Output, generic card with Modbus interface

We have designed and developed generic card with 4 channel of individual ADCs to get better performance and 2 digital NPN outputs with Modbus-RTU protocol interface over RS485 to connect with HMIs and PLCs. It makes life easier to use this card in our customer’s industrial application to develop and integrate with their application.

We provide application customization as per customer need and provide in bulk quantity. For example, shown image of our product is getting used in our OEM customer’s application of fully Automatic Concrete Mixer Control panel. It supports dimension of panel rail mount.

We can also customize size and housing if required in quantity.

Model: LCIC-42RS485

This card can be customized as per requirement of single or any multi channel ADC on a single card based on the production quantity

Key functionalities:

  • 4 24-bits ADC channels with separate ADC chips
  • 2 digital NPN outputs
  • Two transistor output LEDs.
  • Two Modbus LEDs: For activity on Rx, TX . Also shows any communication errors by having one LED continuously ON
  • Eight loadcell LEDs: 1 if healthy and 0 for 0 voltage or any other issue
  • First 8 Holding registers for 4 channel 24 bit Load cell data
  • First 2 Coils for digital output
  • Loadcell, temperature sensors, pressure gauge, current sensor, level sensor and many other 4 to 20mA supported sensors can be connected

Working :

  • Card will continuously read 4 load cell 24 data and put in to first four holding registers
  • Card will work as a Modbus slave device and get commands from PLC/HMI master
  • In first two coils whatever data write command received from master, card will just write the same data to the respective Coil
  • For any error or debugging, respective LEDs state can be verified


  • Controller – STM32G030C8T6 – ARM Cortex M0 PLUS 64MHz controller

  • 4 separate NAU7802 24 bit ADCs – 0 to 3.3V Differential input

  • Conversion rate – 10 samples per seconds. This can be optimized to 100 samples as per application need

  • Measurement accuracy: ±0.05% (typical value)

  • Input voltage reverse connection protection and low-pass filter

  • Isolated RS485 10KV ESD protection

  • 2 digital NPN output

    • 1 RS 485 – For MODBUS-RTU protocol

    • 1 RS 232 TTL – Optional

    • 0.96 Inch OLED displayOptional

    • 4 ADC status LEDs – Communication health check LEDs

    • 2 Digital Output status LEDs

    • 2 (Rx and Tx) RS485 status LEDs – Communication status and error

    • Power consumption – Less than 1W

    • Working temperature: 0℃- +85℃. This can be achieved from -20℃ to +85℃ as per need.

    Key Applications

    Looking for more information, contact us!