Mode-programmable synchronous boost converter raises power efficiency

Diodes Incorporated has released a high-efficiency synchronous boost converter. The DIODES AP72250 is aimed at step-up conversion in consumer and industrial applications where small form factors are a priority. These include battery-powered devices, supercapacitor charging equipment, USB power supply units, supercapacitor charging equipment, power banks, and metering systems.

The device supports a 900kHz switching frequency with a 20µA IQ. It covers a wide input voltage range between 0.6V and 5.5V, with a minimum 1V input startup and a 1.7V to 5.5V output voltage range. Integrated into this boost converter are a 20mOhm high-side power MOSFET and a 26mOhm low-side power MOSFET.

Various operating modes can be chosen for the device, which can be programmed depending on the users' requirements. They are PFM, USM, and FPWM modes. This selection of modes enables engineers to alter operation under either heavy or light load conditions to maximise efficiency. Even in light load situations, up to 89% efficiency can be achieved. Through its USM mode, switching in the audible frequency range is stopped.

The device offers excellent line and load transient responses and provides a seamless transition between boost and pass-through operation (in applications where this is needed). The device's peak current mode control scheme enables it to handle various input-to-output ratios. Consequently, the number of external components required to support it is notably less than for competing solutions, which keeps the BOM costs down. Undervoltage lockout, thermal shutdown, peak current limit, negative current limit, and output short-circuit protection functions are also included.