Microchip's digital potentiometer family lets designers effortlessly fine-tune systems. With the MCP41U83 and MCP42U83, new ten-bit digital potentiometers are available, offering both SPI and I2C interfaces and storing calibration values in flash memory.

The figure below shows the two-channel version (SKU MCP42U83), which permits digital calibration of analog systems. For example, a multimeter can use a digital potentiometer to set attenuation factors. Once the correct factor has been found, it can be easily restored due to the component's digital nature.

I2C and SPI Interfaces Supported

So far, most digital potentiometers have either an I2C or an SPI bus interface. In the case of the new products, Microchip breaks this tradition and provides both interface types. This means designers can select the bus best suited to the task at hand.

In the functional block diagram shown below, we also see a non-volatile memory cell. This can store the values written into the potentiometer and can be used for calibration.

In terms of update frequency, Microchip promises about 1,000 non-volatile write operations over the component's lifetime. In particular, the data sheet promises the following:

MCP42U83 devices are 10-bit dual-channel digital

potentiometers, having both volatile and non-volatile

MTP memory with 1,000 write cycles.

In terms of performance, the above-mentioned interface transceivers are very flexible. The data sheet goes on to claim the following capabilities:

SPI: 20 MHz Read/Write Operation

I2C: 100 kHz, 400 kHz, 1.7 MHz, and 3.4 MHz Communication Speeds

A Wide Variety of Options

Microchip's new digital potentiometer family is available in various resistance and configuration options. Firstly, SKU MCP41U83 must be procured if a single-channel digital potential meter is needed, whereas SKU MCP42U83 provides two independently addressable digital potentiometers in the same IC housing.

The total resistance can then vary from 5 kOhms to 100 kOhms in five steps. The five kOhm version can be purchased via SKU MCP42U83T-502, while SKU MCP42U83T-103 yields 10 kOhms. The 20 kOhms version is the MCP42U83T-203, while the MCP42U83T-503E/7N provides 50 kOhms. Finally, the MCP42U83T-104 option has a total resistance of 100 kOhms. In all cases, the 10-bit resolution means that the digital potentiometer provides 1024 different value steps.

Finally, all family members are qualified in accordance with AEC-Q 100 Grade 1. This means they can be used in automotive electronics without additional certification.

Conclusion

If a design requires calibration, using a digital potentiometer significantly reduces service efforts. With the MCP41U83/MCP42U83 family, Microchip provides digital potentiometers that are not only fine-grained but can also retain values after calibration. In short, it is a component family that is always deserving of recommendation.