MAXIM MAX5099 Dual, 2.2MHz, Automotive Synchronous Buck Converter with 80V Load-Dump Protection

19-4112; Rev 0; 5/08

EVALUATION KIT AVAILABLE

Dual, 2.2MHz, Automotive Synchronous Buck Converter with 80V Load-Dump Protection General Description Features The MAX5099 offers a dual-output, high-switching-fre- Wide 4.5V to 5.5V or 5.2V to 19V Input Voltage quency DC-DC buck converter with an integrated high-

Range with 80V Load-Dump Protection

side switch. The MAX5099 integrates two low-side MOSFET drivers to allow each converter to drive an Dual-Output DC-DC Converter with Integrated external synchronous-rectifier MOSFET. Converter 1

Power MOSFETs

delivers up to 2A output current, and converter 2 can deliver up to 1A of output current. The MAX5099 inte- Adjustable Outputs from 0.8V to 0.9VIN grates load-dump protection circuitry that is capable of

handling load-dump transients up to 80V for automotive Output Current Capability Up to 2A and 1A

applications. The load-dump protection circuit utilizes

Switching Frequency Programmable from 200k Hz

an internal charge pump to drive the gate of an external

n-channel MOSFET. When an overvoltage or load- to 2.2MHz

dump condition occurs, the series protection MOSFET

Synchronization Input (SYNC)

absorbs the high voltage transient to prevent damage to lower voltage components.

Individual Converter Enable Input and Power-

The DC-DC converter operates over a wide 4.5V to 19V

Good Output

operating voltage range. The MAX5099 operates 180° out-of-phase with an adjustable switching frequency to Low-IQ (7µA) Standby Current (ON/OFF) minimize external components while allowing the ability

to make trade-offs between the size, efficiency, and Internal Digital Soft-Start and Soft-Stop

cost. The high switching frequency also allows these

Short-Circuit Protection on Outputs and

devices to operate outside the AM band for automotive

applications. These regulators can be protected Maximum Duty-Cycle Limit

against high voltage transients such as a load-dump

Overvoltage Protection on Outputs with Auto

condition by using the integrated overvoltage controller.

Restart

This device utilizes voltage-mode control for stable operation and external compensation, so that the loop

Thermal Shutdown

gain is tailored to optimize component selection and transient response. The MAX5099 has a maximum duty Thermally Enhanced 32-Pin TQFN Package cycle of 92.5% and is synchronized to an external clock

Dissipates Up to 2.7W at +70°C

fed at the SYNC input. Additional features include internal digital soft-start, individual enable for each DC-DC regulator (EN1 and Ordering Information EN2), open-drain power-good outputs (PGOOD1 and PGOOD2), and shutdown input (ON/OFF). PART TEMP RANGE PIN-PACKAGE

Other features of the MAX5099 include overvoltage pro- MAX5099ATJ+ -40°C to +125°C 32 TQFN-EP*

tection and short-circuit (hiccup current limit) and ther-

+Denotes a lead-free package.

mal protection. The MAX5099 is available in a thermally

*EP = Exposed pad.

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

Pin Configuration appears at end of data sheet.

Automotive Instrument Cluster Display

Maxim Integrated Products

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.