ISL8117 Synchronous Step-Down PWM Controller

Renesas' ISL8117 is a synchronous buck controller to generate POL voltage rails and bias voltage rails for a wide variety of applications in industrial and general-purpose segments. Its wide input- and output-voltage range makes it suitable for telecommunication and aftermarket automotive applications. The ISL8117 uses the valley current modulation technique to bring hassle-free power supply design with the minimal number of components and complete protection from unwanted events.

The ISL8117 offers programmable soft-start and enable functions along with a power-good indicator for ease of supply-rail sequencing and other housekeeping requirements. In ideal situations, a complete power supply circuit can be designed with 13 external components and provide OV/OC/OT protections in a space conscious 16 Ld 4 mm x 4 mm QFN or easy-to-assemble 6.4 mm x 5 mm 14 Ld HTSSOP packages. Both packages use EPAD to improve thermal dissipation and noise immunity.

The easy-to-design philosophy behind this product makes it suitable for quick-to-market compact power supply designs. The ISL8117 utilizes internal loop compensation and single resistor settings for other functions such as operating frequency and over-current protection. Its current-mode control with V_IN feed-forward enables it to cover various applications even with fixed internal compensations. The unique DEM/skipping mode at light-load dramatically lowers standby power consumption with consistent output ripple over different load levels.