STMicroelectronics Inc. (Geneva) introduced the STw4101 power management chip that integrates all of the functions required for managing battery power and charger control in digital cellular handsets and other battery-powered mobile applications where power and performance requirements are similar.
Housed in a 6mm x 6mm TPGBA package, the STw4101 includes six low dropout analog regulators to supply radio frequency circuits, the baseband chip, audio chip, vibrator and other functions. Two of these LDOs are mask adjustable, two are programmable through an I2C bus and two provide general-purpose fixed supply voltages for 3V and 3.3V supplies. The LDOs require only a 1µF ceramic capacitor. Also included is a programmable dc/dc stepdown converter that can be used to power the baseband and audio LDOs, increasing efficiency.
The STw4101's battery-charging function controls the gate voltage of an external p-channel MOSFET and performs constant voltage and constant current charging for lithium-ion batteries. This function is an independent state machine capable of managing the battery-charge operation independently of the microcontroller.
The STw4101 is available for $1.90 in quantities of 10,000 units.
