Extends battery life in compact sensor nodes while providing efficiency up to 95%
The Diodes Incorporated AP61040 and AP61041 synchronous buck converters deliver up to 400mA from 2.15V to 5.5V inputs for wearables, health monitors, and Bluetooth® low-energy applications.
The AP61040 and AP61041 from Diodes Incorporated are synchronous buck converters for portable sensing products that need long battery run-time and a very small power stage footprint. Both buck converters supply up to 400mA across a 2.15V to 5.5V input range, making them suitable for smart watches, fitness bands, health monitors, Bluetooth® low-energy products, and energy-harvesting designs.
A key advantage is the low quiescent current, which helps to extend operating life in systems that spend most of their time on standby or light-load operation. The AP61040 draws a typical 930nA quiescent current in pulse-frequency modulation mode (PFM), while the AP61041 typically draws 1.2uA. Both buck converters also provide efficiency up to 95%.
The two parts give designers different ways to simplify rail selection. The AP61040 uses one selection pin to choose from among preset feedback voltages of 0.6V, 2.5V, and 3.3V, and supports pulse-width modulation (PWM) operation regardless of load. The AP61041 uses two three-state selection pins to choose from eight preset feedback voltages between 0.6V and 1.8V, suiting low-voltage digital rails in compact sensing platforms.
Integration is high, helping reduce bill-of-materials size and board area. The AP61040 and AP61041 are optimized for use with a 2.2µH inductor and 10µF input and output capacitors, and both buck converters support seamless transition between buck and 100% duty cycle modes. Protection features include under-voltage lockout (UVLO), over-current protection (OCP), short-circuit protection, and over-temperature protection (OTP).