TK65424 Datasheet | TOKO

ADVANCED INFORMATION ADVANCED INFORMATION Features s s s s s s s s s s TK654xx STEP-DOWN CONVERTER WITH BATTERY MONITOR APPLICATIONS s s s s s s Battery Powered Systems Cellular Telephones Pagers Personal munications Equipment Radio Controlled Systems Toys s Minimum External ponent Count (1 coil, 1 cap) s Miniature 6 Pin SOT23L-6 Surface Mount Package Up To 95% Efficient Extremely Low Operating Current (24 µA) Low Quiescent Current (18 µA) Low Ripple Fast Transient Response Linear Dropout Characteristics Short Circuit Protection Regulates Down to 1.8 V Synchronous Rectification Internal Battery Monitor Driving the SB pin low will disable the TK654xx and drop the quiescent current on the input supply to approximately 18 µA. Pulse Current Amplitude control is used to regulate the voltage at the VOUT pin of the IC. When the output voltage of the TK654xx drops below the regulation threshold, a current pulse is transferred from the input supply to the output. The TK654xx utilizes a proprietary control scheme, where the average amplitude of the current pulse is varied depending upon the current loads. The proprietary architecture allows fast transient response and minimal ripple while maintaining ease-of-use and low ponent count. The TK654xx is available in a miniature 6-pin SOT23L-6 surface mount package. TK654xx M DESCRIPTION The TK654xx low power step-down converter is designed for portable battery systems, capable of operating from a single Li-ion battery cell or multiple alkaline or rechargeable (Ni Cd or Ni MH) battery cells (up to 6 V). The TK654xx provides the power switch, synchronous rectifier, and the control circuit for a buck step-down converter. Only two external ponents are required to plete the stepdown conversion. The TK654xx provides laser-trimmed output voltages ranging from 1.8 V to 3.3 V. The low resistance MOSFET switch and synchronous rectifier allow average currents up to 200 m A, while maintaining peak efficiencies up to 95%. A...