R5433 Series

Low Supply Current 3-Cell to 5-Cell Li-ion Battery Protection IC

The R5433 Series are high voltage CMOS-based process protection ICs against over-charge and over-discharge of Li-ion/Li polymer secondary batteries. The R5433 series can detect over-charge voltage, over-discharge voltage of 3, 4 or 5-stacked cells of Li-ion/Li polymer batteries.

The R5433 consists of 10 voltage detectors, a voltage reference unit, an oscillator, a counter, delay circuits, and logic circuits.

When the over-charge voltage is detected, after the IC internally prefixed delay time, the output of COUT becomes "Hi-Z" or "H" depending on the output type. When the over-discharge voltage current is detected, after the setting delay time by the internal constant current source and an external capacitor, the output of DOUT becomes "Hi-Z" or "H" depending on the output type.

After detecting over-charge, when the cell voltage becomes lower than the over-charge released voltage, the over-charge state is released and the output of COUT becomes "L". While after detecting over-discharge, when the cell voltage becomes equal or more than the over-discharge released voltage, then the over-discharge state is released, and the output of DOUT becomes "L".

If breaking wire between the cell and protection board is occurred, the wire breaking is detected, and the output of COUT becomes "Hi-Z" or "H" depending on the output type. After detecting the breaking wire, the cell and the protection board is connected again, the breaking wire detector is released and the output of COUT becomes "L".

Further, the testing time shortening function of the protection circuit board is built in the IC. By setting voltage level of DS pin as same as VDD, the output delay time of over-charge can be shortened into approximately 1/100. By setting DS pin at 3.0V, the output delay time of over-discharge can be shortened into approximately 1/100.

The output type of COUT and DOUT can be designated as CMOS type or N-channel open drain type. The output type of the R5433VxxxAA is N-channel open drain type. The output type of the R5433VxxxAB is CMOS output type. The voltage level of the output of CMOS type is in between VSS and the internal regulator output. Therefore, "H" level is the output of the internal regulator, approximately 3.6V.