The DD30CRTA is a PWM switch-mode battery charger controller for 12V lead-acid battery.The DD30CRTA is specially designed for charging 12V lead-acid battery with trickle charge, constant current charge, over-charge and float charge mode. In over-charge and float charge mode, the regulation voltage is internally set.The constant charge current is programmable with a single sense resistor. Deeply discharged batteries are automatically trickle charged at 17.5% of the programmed.constant charge current until the cell voltage exceeds 75% of the regulation voltage in.over-charge mode. The over-charge is terminated once the charging current drops to 38% of the constant charge current, then DD30CRTA will enter float charge mode. A new charge cycle automatically restarts if the battery voltage falls below 83.95% of the over-charge voltage in float-charge mode. DD30CRTA will automatically enter sleep mode when input voltage is lower than battery voltage.Other features include undervoltage lockout and status indication, etc. Description: TYPE: B-no Terminal Suitable for 1-1000AH 12V Lead-Acid Battery charger Power supply voltage: 15-28VDC(Recommended 16-25VDC) Over Charge Voltage is 14.8V Float Charge Voltage is 13.55V Maximum charge current: 3A Quiescent current: about 1.8mA High PWM Switching Frequency: 300KHz Fixed Over-Charge Voltage Overcurrent protection Automatic Conditioning of Deeply Discharged Batteries Automatic Recharge Charger Status Indication Battery Overvoltage Protection Operating Ambient Temperature 40 to 85 Applications: Car battery charging, Solar battery charging, Mobile Loadspeaker, Lead-Acid Battery Charger, Electric Bicycle Charger, UPS, Portable Industrial, Standalone Battery Chargers Material: PCB colour: Green Package Contents: 1 x Battery Charger Module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.