The nickel cadmium cell is one kind of the alkaline battery. Its volume is small, the capacity is big, the output voltage is steady, is firm and durable. It has been widely applied in the computer and the correspondence domain. It has two methods to charge the nickel cadmium cell: One is the rapid charge rate, namely uses the constant big electric current in the as far as possible short time so that the battery sufficient electricity; Another is the trickling charge, uses the undercurrent the battery to carry on the charge in the long time at the readiness condition, for compensates the energy loss which its reason self-discharging, It makes always to maintain the electric quantity sufficient optimum condition.
To design intelligence nickel cadmium cell battery charger, in the way of battery charging-up , the track monitors the battery the voltage change and the electric current change curve, thus the automatic control charging current and the voltage. To achieve the best charge condition, elimination battery memory effect by the rechargeable as far as possible, lengthen the rechargeable battery the service life. This intelligent battery charger when the battery puts in, has the automatic judgment battery voltage function, chooses whether to this battery discharge, the rapid charge rate, the trickling charge as well as fixed time charges and so on the pattern.
MAX712 is the nickel cadmium cell fast battery charger special-purpose integrated circuit which MAXIM Corporation produces. It has the many kinds of programmable functions, may realize the charging-up automation, the duration of charging, the efficiency high, the easy to operate is flexible.
This article introduce one kind of the method that monolithic integrated circuit programming to control nickel cadmium cell intelligence battery to charger integrated circuit principle, and produce the nickel cadmium intelligence battery charger practical application electric circuit which this chip constituted.
