IT home March 5 news, according to the core sheng technology released, for the smart water meter industry, China mobile core sheng technology rely on its own MCU main control chip, NB module and security chip, developed a high-precision, low-cost, ultra-low power consumption non-magnetic water meter solution, can provide cost-effective integration services including tariffs.
First, the working principle of non-magnetic water meter
XINSHENG
The non-magnetic water meter scheme achieves metering by detecting the sine wave attenuation process. The dial rotor of the water meter is divided into two areas: metal dial and non-metal dial, the inductor L is a fixed inductor, and the capacitor C forms an LC oscillation circuit.
After the LC circuit is charged, the MCU obtains a sine wave in the LC oscillation circuit by sensing the voltage across capacitor C.
When the inductor is in the metal region, an inductor eddy current is formed, resulting in an increase in electrical energy consumption and an acceleration of the attenuation speed of the sine wave; when the inductor is in the non-metallic region, there is no eddy current, and the attenuation rate of the sine wave is relatively slow.
By detecting the speed of sine wave attenuation, the MCU accurately identifies the position of the dial rotor, and then determines the position of the dial and the number of turns, so as to achieve the purpose of measurement.
2. Introduction to the program
This scheme is based on the non-magnetic water meter scheme of the MCU chip CM32M10xA of Semater Technology.
The solution circuit structure is simple, and the non-magnetic metering is implemented by a dedicated low-power rotary counter (LPRCNT) module built into the CM32M10xA, and the external circuit only needs an inductor and capacitor device. Through the 3-channel oscillation circuit, while completing high-precision metering, it can also realize the functions related to metering stabilization, disc shedding alarm, and strong magnetic proximity alarm.
With the help of the LPRCNT module, this solution enables automatic counting when the CM32M10xA is in Stop2 mode, and wakes up to operating mode for data processing and transmission when the sensor reading changes and the threshold is triggered, achieving ultra-low power consumption.
Third, the advantages of the program
1. The solution is simple and low cost
This scheme is based on the MCU single chip design, the metering part only needs inductance, capacitor, simple solution, high stability and reliability, low cost.
2. Low power consumption of automatic metering
The solution can realize automatic counting and fast wake-up to meet the low-power requirements of metering application scenarios.
3. Strong anti-interference ability
This solution has strong environmental adaptability, realizes strong magnetic proximity alarm, disc shedding alarm, high measurement accuracy, and can be installed in complex environments.
4. The product can be quickly landed
Provide the overall solution of MCU + communication + security, the relevant software and hardware design data is complete and detailed, which can support smart metering solution providers and terminal manufacturers to quickly realize productization.
Fourth, MCU chip introduction
1. CM32M10xA series chips introduced
The CM32M10xA series is the first general-purpose MCU of Sexus Technology, using a 32-bit ARM Cortex-M4 core, supporting floating-point arithmetic and DSP instructions, operating at a maximum operating frequency of 108MHz and flashing up to 128KB.
2. CM32M10xA series chip resource overview
In addition to floating-point arithmetic units, rich timer resources, and high-performance analog peripherals, the chip also integrates LPRCNT, TSC, and SegLCD corresponding feature modules.
3. CM32M10xA series chip advantages
Performance
With a Cortex-M4 core, 108MHz main frequency, a single clock cycle multiply-accumulate (MAC) unit, optimized single-instruction multiple data (SIMD) instructions, saturation operation instructions, and a single-precision floating-point unit (FPU), it has great advantages over the Product of the Cortex-M3 core in complex algorithm implementation.
High configuration
Compared with the competitive resources, the 12×Timer, 6× Uart, 1×12bit DAC, 1× low power counter (LPRCNT), 24-channel touch sensing controller (TSC), 8COM segment lcd display driver (8*40SegLCD).
High security
Built-in hardware algorithm accelerator to support mainstream encryption algorithms on the market.
Low power consumption
Advanced 40nm process with a significant power advantage over competitors.