Research and Implementation of Constant Current Source Charger

Abstract

this paper introduces a kind of the rectifier circuit, adjustable constant current charging circuit, detecting voltage circuit, display circuit and power circuit of six parts of constant current source charger design scheme. The charger using op-amp composition adjustable constant current charge, constant current source circuit to avoid the constant voltage charging and lack of such as output voltage will vary with load, using a 555 timer consists of oscillator and general TL082 J FET dual operational amplifier, compared with 3V voltage reference test voltage circuit to realize full automatic disconnection functions. Introduction Nowadays, for the battery has been the focus of people care about, right and good charging method can ensure the battery life.So some constant voltage and constant current charge appeared, while constant voltage charging can satisfy normal charging, but the output voltage will change due to load changes.And The vast majority of constant current circuit is regulated by using the three-step chip to stabilize voltage charging.In this paper, the charger can not only at a constant current for two batteries recharged but also output voltage does not change with load. It can automatically displayed when the battery is full of charge, and stopped charging automatically cut off power supply. Design of this project The overall block diagram simple constant-current battery charger 5 as shown in figure 1 is made up of rectifier circuit, adjustable constant current circuit, detecting voltage circuit, display circuit and charging power supplying circuit five parts to form a complete charging circuit. Fig.1. simple battery overall block diagram of adjustable constant current charging circuit The function of the transformer rectifier circuit is 220V alternating current (AC) in the grid will be converted to the appropriate current and voltage signals, thus providing signal for subsequent circuit.The function of adjustable constant current circuit is charging constantly current source circuit by using adjustable constant current consisted of op-amp composition.The function of detecting voltage circuit is the device of comparing , compare the voltage across the battery control relay work, so as to realize automatically cut off power supply when a full charge.The function of the circuit of charging display are using 555 thanks oscillator with LED will stop charging status and status display of the charging circuit.The function of the regulated power supply circuit is International Industrial Informatics and Computer Engineering Conference (IIICEC 2015) © 2015. The authors Published by Atlantis Press 88 providing all of the above circuit DC voltage. The main unit circuit design