The MAX5099 offers a dual-output, high-switching-frequency DC-DC buck converter with an integrated high-side switch. The MAX5099 integrates two low-side MOSFET drivers to allow each converter to drive an external synchronous-rectifier MOSFET. Converter 1 delivers up to 2A output current, and converter 2 can deliver up to 1A of output current. The MAX5099 integrates load-dump protection circuitry that is capable of handling load-dump transients up to 80V for automotive applications. The load-dump protection circuit utilizes an internal charge pump to drive the gate of an external n-channel MOSFET. When an overvoltage or load-dump condition occurs, the series protection MOSFET absorbs the high voltage transient to prevent damage to lower voltage components.
The DC-DC converter operates over a wide 4.5V to 19V operating voltage range. The MAX5099 operates 180° out-of-phase with an adjustable switching frequency to minimize external components while allowing the ability to make trade-offs between the size, efficiency, and cost. The high switching frequency also allows these devices to operate outside the AM band for automotive applications. These regulators can be protected against high voltage transients such as a load-dump condition by using the integrated overvoltage controller.
This device utilizes voltage-mode control for stable operation and external compensation, so that the loop gain is tailored to optimize component selection and transient response. The MAX5099 has a maximum duty cycle of 92.5% and is synchronized to an external clock fed at the SYNC input.
Additional features include internal digital soft-start, individual enable for each DC-DC regulator (EN1 and EN2), open-drain power-good outputs (PGOOD1 and PGOOD2), and shutdown input (ON/OFF).
Other features of the MAX5099 include overvoltage protection and short-circuit (hiccup current limit) and thermal protection. The MAX5099 is available in a thermally enhanced, exposed pad 5mm x 5mm, 32-pin TQFN package and operates over the automotive -40°C to +125°C temperature range.
Applications
- Automotive AM/FM Radio Power Supply
- Automotive Instrument Cluster Display
