The HL7543WL01 from Halo Microelectronics is a Synchronous Buck DC-DC Converter that converts an input voltage of 2.3 - 5.5 V to an output voltage of 0.66 - 3.4 V. It has an efficiency of over 90%. This converter operates at a frequency of 1.2 MHz, which greatly reduces the value of external components. It allows a wide range of output capacitors to be used to optimize output voltage stability during load transients. This DC-DC converter utilizes pulse frequency modulation (PFM) to provide stable conversion efficiency under moderate to light loads. It automatically switches to fixed-frequency pulse width modulation (PWM) operation under high load conditions, thereby ensuring minimum output voltage ripples and optimal load transient responses.
This buck converter supplies less than 270 nA of current during shutdown mode, which reduces the power consumption for optimal power management. It is equipped with input under voltage lockout (UVLO), short-circuit protection (SCP), and thermal shutdown capabilities to prevent false triggers and over-current-related damages. This DC-DC converter is available in a wafer-level package that measures 1.6 x 0.9 mm and is ideal for smartwatches, fitness trackers, and wearable applications.