The RT9535B is a PWM switch mode battery charger controller to fast charge single or multiple Li-Ion, NiMH and NiCd batteries, using constant current or constant voltage control. Maximum current can be easily programmed by external resistor. The constant voltage output can support up to 22V with 0.5% accuracy.

A third control loop limits the input current drawing from the adapter during charging. This allows simultaneous operation of the equipment and fast battery charging without over loading to the adapter.

The RT9535B can charge batteries from 2.5V to 22V with dropout voltage as low as 0.4V. A logic output indicates Li-Ion full charge when current drops to 17% of the full-scale programmed charge current.

The RT9535B is available in the WQFN-24L 4x4 package.


  • Notebook Computers
  • Portable Instruments
  • Chargers for Li-lon, NiMH, NiCd and Lead Acid Rechargeable Batteries
Key Spec.
Status NRND
Vin (min) (V) 4.5
Vin (max) (V) 28
Battery Charge Voltage (max) (V) 22
Battery Charge Current (max) (A) 2
Status Indicator Yes
Charger Type Switching
Input Source AC Adapter;USB
Features Adjustable Current Limit;Adjustable Soft-Start;Current Mode Control;Enable Input;OCP;SCP;UVP
Package Type WQFN4x4-24
Built-in Power MOSFETs Yes
  • Fast Charging for Li-Ion, NiMH and NiCd Batteries
  • Adjustable Battery Voltages from 2.5V to 22V
  • High Efficiency : Up to 95%
  • Charging Current Programmed by Resistor
  • Precision 0.5% Charging Voltage Accuracy
  • Provide 5% Charging Current Accuracy
  • Input Current Limit Maximizes Charging Rate
  • 500kHz Switching Frequency
  • Flag Indicates Li-Ion Charge Completion
  • Auto Shutdown with Adapter Removal
  • Only 10μA Battery Reverse Current when Idle
TitleLast UpdateDownload
High Efficiency Switching Mode Battery Charger2014/07/17