A rotation measurement solution using magnetic sensors that can be measured for a long period of time using battery power.

Rotation Detection Solution

The movement of the rotating body is converted into an electrical signal using magnetic sensors and coil sensors, and the rotation measurement is achieved by measuring the pulses. One of the main applications of this rotation measurement technology is gas and water meters which need to be battery powered and must operate for a long period of time.

In order to meet these requirements, Renesas offers rotation measurement solutions that utilize microcontrollers that operate in a low power consumption mode.


Devices suitable for rotation measurement

Renesas offers a wide lineup of devices suitable for battery-powered rotation measurements.

The RL78/I1D utilizes analog functions such as 12-bit A/D converters and window comparators along with a data transfer controller (DTC) to measure the rotation using coil sensors. In addition to low power consumption operation of 124μA at 1MHz, it is equipped with a medium-speed oscillator capable of 4μs high-speed wake-up which contributes to the miniaturization of batteries in the customer system. Also, we have a lineup of 20 to 48-pin small pin packages that are ideal for small sensor applications.


The RL78/H1D utilizes a sampling output timer/detector function to perform rotation measurement using a magnetic sensor with low power consumption. Measurement results can be displayed on an external display with the LCD controller/driver that supports three LCD drive voltage generation methods (internal boost, capacity split and external resistance split). In addition, it is equipped with a UART that is capable of up to 19200bps communication in subsystem clock (38.4kHz) operation mode, allowing it to communicate externally at very low power, making it ideal for applications such as smart gas meters and smart water meters.

*Bluetooth® Low Energy, Sub-GHz/Wi-SUN, LoRa® Solution


Microcontroller Function Evaluation Board Solution Kit

There are two types of evaluation boards available, a flat coil-type rotation measurement solution kit using an RL78/I1D with a sampling output timer/detector, and an RL78/H1D evaluation board with external sampling function.

Rotational Flow Demonstration Kit “Flow it!”

回転計測ソリューションキット“Flow it!”

RL78/H1D Evaluation Board


Application Note


RL78/H1D Datasheet Download
RL78/I1D Datasheet Download


Application notes

RL78 Troubleshooting of the LCD controller/driver r01an3996ej0100
RL78/I1D Serial Array Unit (UART Communication) CC-RL r01an3336ej0100