LCD-targeted RL78/L13 with on-chip segment driver
The Renesas R5F10WLAAFA#10 is a 16-bit RL78/L13-series MCU clocked at 24 MHz, built around the RL78 core with 16 KB flash and 4 KB data EEPROM on a single die. The 1 KB RAM (1K x 8) handles the display buffer and control stack for segment LCD applications without external SRAM. The 64-LQFP package (12x12 mm) brings out 42 I/O pins, enough to drive a segment LCD panel, a keypad matrix, and a handful of sensor or actuator lines. On-chip peripherals include DMA for memory-to-LCD transfers, a PWM timer for backlight dimming, and a windowed watchdog timer (WDT) for safety-critical code paths.
Supply flexibility and analog front-end
The 1.6 V floor also supports two alkaline cells in series down to their end-of-life voltage. The 9-channel ADC (8- or 10-bit resolution) reads battery voltage, temperature sensors, or potentiometer inputs alongside the LCD drive. The ROHS3 compliance clears EU RoHS and China RoHS without exemption paperwork.
Connectivity and peripheral mix for metering and HMI
Serial interfaces include CSI (clocked serial interface, compatible with SPI), I²C for low-pin-count sensor buses, LINbus for automotive sub-networks, and UART/USART for debug or Modbus RTU links. The peripheral set — DMA, LCD controller, LVD, POR, PWM, WDT — is tailored for applications that wake from sleep, sample a sensor, update a display, then go back to standby. The on-chip LCD controller drives segment displays directly, eliminating a separate driver IC. Combined with the 4 KB EEPROM for calibration constants or last-state retention, the part suits gas/water meters, thermostats, and portable medical monitors where non-volatile storage must survive frequent write cycles.