The AP62500 and AP62800 have continuous output current ratings of 5.0 and 8.0A respectively. According to Diodes, they offer designers the flexibility needed to develop point-of-load (PoL) solutions that are optimised for either efficiency or size. They are also claimed to enable compact implementations with minimal component count, for example in  mass-market consumer products, e.g., 5V and 12V distributed power bus supplies, television sets and monitors, white goods and small home appliances, FPGA, DSP, and ASIC supplies, home audio, network systems, gaming consoles, consumer electronics, and general purpose PoLs.

Both buck converters have wide input voltage ranges. The AP62500 covers 4.5V to 18V and the AP62800 covers 4.5V to 17V, making both synchronous buck converters suitable for 5V and 12V rail applications. Output voltages can be adjusted down to 0.6V. They also have three selectable switching frequencies (400kHz, 800kHz and 1.2MHz), which allow engineers to prioritise elevated conversion efficiency or to focus on developing a compact form factor.

There are also three selectable operating modes, namely, pulse frequency modulation (PFM) for improved light-load efficiency, pulse width modulation (PWM) for reduced output voltage ripple and ultrasonic (USM) for avoiding audible frequency range while ensuring the switching frequency stays above 20kHz.

RDS(on) is low in relation to both the high side MOSFET (47mΩ for AP62500 and 22mΩ for AP62800) and low-side MOSFET (18mΩ for AP62500 and 10mΩ for AP62800). This helps to improve step-down conversion efficiency levels. A low quiescent current (IQ) is also achieved while in PFM mode (195μA typical), reports the company, to enhance light load efficiencies.

The design of these buck converters minimises electromagnetic interference (EMI) issues, says the company. The proprietary gate driver design mitigates switching node ringing without having to extend MOSFET turn on/turn off times, which would otherwise impact high-frequency switching capabilities. Constant on-time control results in fast transient response and low output voltage ripple and improves loop stabilization. The ability to adjust soft-start time also protects against the risk of damage from inrush currents.

Both the AP62500 and AP62800 are supplied in a 12-pin V-QFN2030 package.

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