The MAX5099 is 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 provides two independent buck converters in a single 32‑pin TQFN package. Converter 1 supplies up to 2 A and Converter 2 up to 1 A, both operating from a wide 4.5 V‑to‑19 V input range. The device features an integrated high‑side switch, low‑side MOSFET drivers, and an external synchronous‑rectifier MOSFET for high‑efficiency operation.
Key features include programmable switching frequency (200 kHz‑2.2 MHz), 80 V load‑dump protection, internal digital soft‑start, individual enable and power‑good outputs, and protection against over‑voltage, short‑circuit, and thermal overload. The converter operates from –40 °C to +125 °C and dissipates up to 2.7 W at +70 °C.
| Input Voltage Range | 4.5 V to 19 V |
|---|---|
| Output Current (Converter 1) | 2 A |
| Output Current (Converter 2) | 1 A |
| Switching Frequency | 200 kHz to 2.2 MHz (programmable) |
| Maximum Duty Cycle | 92.5 % |
| Operating Temperature Range | -40 °C to +125 °C |
| Standby Current (ON/OFF) | 7 µA |
| Adjustable Output Voltage | 0.8 V to 0.9 V |
| Load‑Dump Protection | 80 V transient capability |
The device can absorb load‑dump transients up to 80 V.
It provides two independent converters; Converter 1 up to 2 A and Converter 2 up to 1 A.
The device operates from –40 °C to +125 °C.
It accepts a wide input voltage range from 4.5 V to 19 V.