Gas meters require monitoring of various sensor information to measure gas usage and to safely supply gas, an LCD display function to show this information and a data communication function to communicate with external devices. Also, these functions must stably operate with limited battery capacity for the period specified.
To support various LCD panels, Renesas offers a lineup of the RL78/L1x microcontrollers (MCUs) supporting three LCD drive voltage generation methods (external resistance division method / internal voltage boosting method / capacitor split method). In addition to RL78/L1x, Renesas has RL78/H1D equipped with UART that can communicate up to 19200 bps with subsystem clock (38.4 kHz), sampling output timer / detector function suitable for rotation detection by MR sensor, it is suitable for diaphragm gas meter construction.
|Block||Semiconductor device||Recommended products||Features, etc.|
|Main controller||MCU||RL78/L1x||32 MHz, 16-bit, True low power,
On-chip LCD controller/driver
|RL78/H1D||32 MHz, 16-bit, True low power,
On-chip LCD controller/driver, On-chip timer for MR sensor
|Communication||Sub-GHz RF Transceiver||RAA604S00||RF frequency range: 863 to 928 MHz, IEEE802.15.4g / 4e compliant hardware function|
|MCU built-in Sub-GHz RF Transceiver||RL78/G1H||32 MHz, 16-bit CPU, RF frequency range: 864 to 928 MHz|