The FAN23SV04T is a highly efficient, integrated synchronous buck regulator for use in tracking applications, such as DDR termination rails. The VDDQ input includes an internal 2:1 resistive voltage divider to reduce total circuit size and component count. The regulator operates with an input range from 7 V to 18 V and supports up to 4 A load currents. The device can operate from a 5 V rail (±10%) if VIN, PVIN, and PVCC are connected together to bypass the internal linear regulator. This device utilizes onsemi’s constant on-time control architecture to provide excellent transient response and to maintain a relatively constant switching frequency. Switching frequency and sourcing over-current protection can be programmed to provide a flexible solution for various applications. Output over-current, and thermal shutdown protections help prevent damage during fault conditions. A hysteresis feature restarts the device when normal operating temperature is reached.