This is a reference design of a digital load cell using MCU with high-precision AFE, RX23E-A. Using the RX23E-A makes an external dedicated AFE unnecessary, thereby miniaturizing a board.
In the digital load cell, a board mounting ADC and MCU, and a load cell are combined into a single unit, accordingly, the board is required to be small. RX23E-A realizes MCU and AFE on a single chip, not requiring an external dedicated AFE, thereby suitable to miniaturizes a board. This reference design is a design for a 22×16-millimeter small board which can be combined with a load cell. This tiny board incorporates RS-485/RS-422 transceiver, ISL3152E, as well as RX23E-A. RX23E-A performs A/D conversion, digital filter processing, calibration and physical quantity conversion (Voltage to Weight) on a single chip. ISL3152E transmits weight values to host devices with digital communication such as Modbus. When creating this reference design, we evaluated weight measurement errors by incorporating this small board into a load cell. Non-linear errors of the weight measurement are within ±0.01%max.span. Accordingly, it is confirmed that the precision specifications of a general load cell are well satisfied
- Realizes 22×16-millimeter small board
- Small enough to be incorporated into a digital load cell.
- Mounts MCU with high-precision AFE, RX23E-A
- Not requiring an external dedicated AFE, contributing to reduction in BOM cost and board mounting area.
- A single chip of RX23E-A realizes high-precision weight measurement including digital filter processing and calibration.
- Mounts RS-485/RS-422 transceiver, ISL3152E
- Enables digital communication such as Modbus
- Application note
- Circuit diagram(included in application note)
- BOM(included in application note)
- Gerber Files