The LM5163H-Q1 is an easy-to-use, ultra-low I_Q constant on-time (COT) synchronous step-down buck regulator. With integrated high-side and low-side power MOSFETs, the LM5163H-Q1 is a low-cost, highly efficient buck converter that operates from a wide input voltage of 6 V to 100 V, delivering up to 0.5-A DC load current. The LM5163H-Q1 is available in an 8-pin SO PowerPAD integrated circuit package with 1.27-mm pin pitch for adequate spacing in high-voltage applications. This constant on-time (COT) converter is designed for low-noise, high-current, and fast load transient requirements, operating with a predictive on-time switching pulse. Over the input voltage range, input voltage feedforward is employed to achieve a quasi-fixed switching frequency. A controllable on-time as low as 50 ns permits high step-down ratios and a minimum forced off-time of 50 ns provides extremely high duty cycles, allowing V_IN to drop close to V_OUT before frequency foldback occurs. At light loads, the device transitions into an ultra-low I_Q mode to maintain high efficiency and prevent draining battery cells connected to the input when the system is in standby. The LM5163H-Q1 implements a smart peak and valley current limit detection circuit to ensure robust protection during output short-circuit conditions. Control loop compensation is not required for this regulator, reducing design time and external component count.

The LM5163H-Q1 incorporates additional features for comprehensive system requirements, including an open-drain power good circuit for the following:

• Power-rail sequencing and fault reporting
• Internally-fixed soft start
• Monotonic start-up into prebiased loads
• Precision enable for programmable line undervoltage lockout (UVLO)
• Smart cycle-by-cycle current limit for optimal inductor sizing
• Thermal shutdown with automatic recovery

These features enable a flexible and easy-to-use platform for a wide range of applications. The LM5163H-Q1 supports a wide range of end-equipment systems requiring a regulated output from a high input supply with the ability to support high output power at high ambient temperatures. The following are examples of such end equipment systems:

• 48-V automotive mild-hybrid systems
• High-temperature Automotive ADAS and powertrain systems

The pin arrangement is designed for a simple layout requiring only a few external components.