The RT8059 is a low-cost high-efficiency PWM step-down DC/DC converter. This small IC delivers up to 1A output current. It has a wide input voltage range from 2.8V to 5.5V, making it suitable for a variety of power sources.
The RFM69HW module is available in 3 different operating frequencies, 433MHZ, 868MHz, and 615Mhz. While buying the module we should consider the license-free ISM (Industry Scientific and Medical) frequency band in our respective countries.