The tax control cash register is a kind of cash register with tax calculation function with legal seriousness and indestructibility. It is equipped with a tax calculation memory that is automatically recorded but cannot be changed or erased, which records the daily business data and tax payable, and is a proof of tax payment to the tax paying authority.
The records and relevant time and other information of the goods sold by the taxpayer in the tax control cash register can be retained in the machine for 5~10 years, and cannot be modified or cleared. The relevant data is read out by the tax department with a special IC card for easy inspection. Each tax control cash register is unique after being issued and processed by the tax department. This tax control cash register has a power-off protection function, that is, when there is a sudden power failure, the data can still be stored, and the operation process of IC reading and writing card can be carried out for a short time, and there is a backup power supply for protection. There are two solutions for backup power: supercapacitors and batteries. Compared with batteries, supercapacitors have the characteristics of large discharge current, long cycle life, and environmental protection.
The use of supercapacitors enhances the reliability of the tax collector and eliminates the need for battery maintenance and replacement every 2-3 years. In the event of a power failure, the supercapacitor provides energy to the control circuit, the CPU can execute the data storage process in a short time, and after the reading and writing is completed, the capacitor provides an instantaneous pulse current (a few A) to eject the IC card.