GENERAL DESCRIPTION
The SC6054 is a cost-effective, fully integrated high input voltage single-cell Li-ion battery charger. The charger uses a CC/CV charge profile required by Li-ion battery. The charger accepts an input voltage up to 24V but is disabled when the input voltage exceeds the OVP threshold, typically 6.8V, to prevent excessive power dissipation. The 24V rating eliminates the over-voltage protection circuit required in a low input voltage charger. The charge current and the end-of-charge (EOC) current are programmable with external resistors. When the battery voltage is lower than 2.55V, the charger preconditions the battery with typically 20% of the programmed charge current. When the charge current reduces to the programmable EOC current level during the CV charge phase, an EOC indication is provided by the 𝐶𝐻𝐺 ̅̅̅̅̅̅ pin, which is an open-drain output. An internal thermal foldback function protects the charger from any thermal failure. Two indication pins ( 𝑃𝑃𝑅 ̅̅̅̅̅̅ and 𝐶𝐻𝐺 ̅̅̅̅̅̅ ) allow simple interface to a microprocessor or LEDs. When no adapter attached, the charger draws less than 1μA leakage current from the battery. The SC6054 is available in Green DFN-2×2-8L packages and is rated between -40℃ to +85℃ temperature range.
FEATURES
 Complete Charger for Single-Cell-Li-ion or Polymer Batteries  Integrated Pass Element and Current Sensor  No External Blocking Diode Required  Low Component Count and Cost  Programmable Charger Current  Programmable End-of-Charger Current  Charger Current Thermal Foldback for Thermal Protection  2.55V Trickle Charge Threshold  6.8V Input Over-Voltage Protection  24V Maximum Voltage for the Power Input  Power Presence and Charge Indications  Less than 1μA Leakage Current from the Battery When No Input Power Attached  Available in Green DFN-2x2-8L Packages
OPERATION
The SC6054 charges a Li-ion battery using a CC/CV profile. The constant current IREF is set with the external resistor RIREF (see Figure 1) and the constant voltage is fixed at 4.2V (or 4.3V, or 4.35V). If the battery voltage is below a typical 2.55V trickle charge threshold, the SC6054 charges the battery with a trickle current of 20% of IREF until the battery voltage rises above the trickle charge threshold. Fast charge CC mode is maintained at the rate determined by programming IREF until the cell voltage rises to 4.2V (or 4.3V, or 4.35V). When the battery voltage reaches 4.2V (or 4.3V, or 4.35V), the charger enters a CV mode and regulates the battery voltage at 4.2V (or 4.3V, or 4.35V) to fully charge the battery without the risk of over charge. Upon reaching an end-of-charge (EOC) current, the charger indicates the charge completion with the 𝐶𝐻𝐺 ̅̅̅̅̅̅ pin, but the charger continues to output the 4.2V (or 4.3V, or 4.35V) voltage. Figure 3 shows the typical charge waveforms after the power is on.