Do you know the basic composition of intelligent water meters? In fact, besides the two components of the base meter and the control valve, the main control circuit is also a very important part. The following experts from the intelligent water meter manufacturer will introduce the related knowledge of the main control circuit to you.
CPU
Intelligent water meter is a small battery power supply system. Therefore, the selection of CPU should focus on low voltage, low power consumption and high load capacity. Microchip's PIC series microcontrollers have obvious advantages in this respect. And its unique RISC structure and the Harvard bus structure can save half of the program code and increase the instruction speed by about five times compared with the same kind of microcontroller, so it is an ideal choice.
Data Memory
Data memory is used to store all kinds of information about water meters, such as water purchases, water consumption, user coding and so on, which are calculated and processed by CPU. ATMEL's 256*8-bit E2PROM general memory AT24LC01 is easy to use, and its price is very low. It can fully meet the requirements of use.
IC card
IC card reading and writing module is the logic interface circuit between the main control circuit and IC card. It should first realize the supply of power to IC card, and meet the requirements of non-live plug-in (if live plug-in, it may cause damage to IC card, or even damage IC card), which can be achieved through both hardware and software.
In addition, clamp protection diodes should be added to all IC card interfaces, which can strictly control the voltage on each pin between - VD~VCC+VD.
On-off valve control
The switching of water meter valve is realized by CPU according to certain switching conditions. There are two main points in the design of switching valve control: one is to control the current output time of the switching valve circuit in software, that is, the circuit lead-on time is too long, the battery consumes too much energy; the other is to switch the valve reliably because of too short time. Secondly, there should be an energy storage circuit for the shutdown of the valve in the hardware circuit. When the power supply is out of power, the circuit can release electric energy in time and close the valve.
Intelligent water meter manufacturers to provide you with satisfactory products!