KA35S280/281

Lead-Acid Battery Charger

2011 Nov 18

© 2011

2

Features:

 Optimum Control for Maximum Battery Capacity and Life

 Applicable to Various Types of Lead Battery

 Pin-Selectable Charge Algorithms (3 Step Voltage, Current, or Pulsed Charge)

 Automatically Shorted, Opened, or Damaged Cells Detections

 Automatically Battery Removal Detection

 Charge Condition LED Indicator Outputs (On, Pulsed, Off)

 Automatic Correction of Charging Current and Voltage Based on Current Temperature

 Maximum and Minimum Battery Temperature Protection

 Pre-Charge Qualification (Initial Trickle Charge for Deeply Discharged Batteries)

 Cycle/Float Button (For In-System Battery Charge Condition)

 Adjustable Charging Time Control by Changing the External Current Resistor

 Faster Charge Time Button

 Externally Disabling Charge Button

 Switch Mode Constant Current Generation

 Pb-Free (RoHS Compliant)

Applications:

 Handheld Equipment

 Portable Instruments and Communications

 Power Conditioning for Battery Systems

 Telecommunications

 Power Utility

 Emergency Lighting

 Control System

 Fire & Security

 Renewables

 UPS

Description:

The KA35S28X series of battery charger controllers contain all of the necessary circuitry to

optimally control the charge and hold cycle for sealed lead-acid batteries. These integrated

circuits monitor and control both the output voltage and current of the charger through three

separate charge states; a high current bulk-charge state, a controlled over-charge, and a

precision float-charge, or standby, state.

The Pulse-Width Modulator (PWM) provides control for high-efficiency current and voltage

regulation. It allows the KA35S28X to control 3-step constant-voltage, constant current, or

pulsed-current charging. A charge cycle begins when power is applied or the battery is

replaced. For safety, charging is inhibited until the battery voltage is within configured limits.

If the battery voltage is less than the low-voltage threshold, the KA35S28X provides trickle-

current charging until the voltage rises into the allowed range. This procedure prevents high-

current charging of cells that are possibly damaged or reversed.

Charging is inhibited anytime if the temperature of the battery is outside the configurable,

allowed range.

All voltage thresholds, in accordance with battery manufacturer's

recommendations, are change proportional to the temperature conditions.

KA35S28X can receive the types of charging algorithm or stop charging commands from its

mode selection pins. Also it can change the voltage thresholds when battery is connected to

an electronic circuit or raises charge speed by 25% only by individual pins that named as

"cycle/float" and "faster charge".