When it comes to replacing the electricity meter, everyone has their own reasons.

Today, I would like to introduce to you the single-phase electronic energy meter solution of Renesas Electronics. This solution integrates Renesas 16-bit microcontroller RL78/I1C with enhanced analog functions, low-dropout linear regulator ISL80505, low-power, high-speed RS-485/RS-422 transceiver ISL8485E and a high isolation voltage photocoupler PS2514L. The combination of these products makes the solution have ultra-low power consumption and cost.

The core of the Renesas single-phase electronic energy meter is the high-performance RL78/I1C MCU, which is also the key to the solution's low power consumption and high-precision measurement. The Renesas RL78/I1C microcontroller has integrated functions for high-precision smart energy measurement, built-in 24-bit ΔƩA/D converter, up to 256 KB of flash memory, 32-bit MAC (multiplication and accumulation) function, RTC independent power supply and AC off operation enhanced battery pin (VBAT) function, which not only strengthens the system's safety functions but also improves the arithmetic operation speed.

In terms of LDO (single output low dropout regulator) selection, Renesas single-phase electronic energy meter solution selected ISL 80505 which can output 500mA current. This product series adopts sub-micron BiCMOS process to provide first-class analog performance and overall value. Compared with bipolar LDO, this CMOS LDO consumes much less quiescent current than bipolar LDO, which can bring higher efficiency and smaller footprint to the system.

Photocouplers play a vital role in any electronic circuit. The Renesas high isolation voltage optical converter PS2514L-1 is used in this solution. This device is an optically coupled isolator consisting of a GaAs light emitting diode and an NPN silicon phototransistor, which can achieve relatively high switching speeds with a high load resistance of several kΩ.

In fact, various rumors about electronic meters have been spread on the Internet for a long time, and most of them are caused by the high sensitivity of the meters. However, this cannot prevent the meters from developing towards electronic and intelligent development. Nowadays, the application of electric energy in production and life has matured, and electronic energy meters with various performances and functions have become the main force in energy measurement. Renesas single-phase electronic energy meter solution can not only reduce power consumption and costs, but also allow you to have a "clear and accurate" understanding of electricity usage.