BL6523GX is a wide range single-phase multi-function electronic energy metering chip. It integrates 3 analog circuits such as high precision sigma delta ADC, reference voltage, power management and other analog circuit modules, as well as digital signal processing circuits for processing active power, depending on power and current and voltage value. It is suitable for single-phase multifunctional or single-phase power line carrier energy meter applications.
Features

High accuracy. In the dynamic range of input (6000:1), the nonlinear measurement error is less than 0.1%.
It can accurately measure active power in two directions and output fast output pulse (CF).
Two current sampling terminals, sampling the firing line and zero line current.
The effective value of voltage and double current, power factor
Voltage loss and fault detection function
It has anti sneaking function and programmable anti submarine threshold setting.
Programmable gain adjustment and phase compensation
It has a UART communication interface for data transmission.
External crystal oscillator 3.58MHz
Single working power 5V, low power 25mW (typical value)

Resources
Datasheet