The LTC3807 features a robust 1.1 Ohm on-chip MOSFET gate driver. This product operates at a selectable fixed frequency between 50kHz and 900kHz and can be synchronized to an external clock in the 75kHz to 850kHz range. Users can select continuous operation, pulse skipping, or low ripple Burst Mode® operation during light load conditions. The product's current mode architecture provides easy loop compensation, fast transient response, and excellent line regulation. Output current sensing is achieved by measuring the output inductor DCR (drop across the output inductor) for maximum efficiency, or alternatively by using an optional sense resistor. Current foldback limits MOSFET heat dissipation during overload conditions. Additionally, it features low 95ns minimum on-time for high step-down ratio, maximum 99% duty cycle for low dropout voltage, an internal LDO powering the gate driver, and a power good signal function.

The LTC3807 is available in a 20-pin 3mm x 4mm QFN and 20-pin TSSOP package with enhanced thermal performance. For extended and industrial grade operation, it is available in four temperature grades: –40°C to 125°C, automotive grade for high temperature at –40°C to 150°C, and military grade at –55°C to 150°C. Pricing starts at $2.30 per unit for quantities of 1,000. For more information, visit www.linear.com/product/LTC3807.

Photo Caption: Low Quiescent Current Synchronous Step-Down Controller

Product Features: LTC3807

• Wide input voltage range: 4V to 38V

• 50μA quiescent current

• Wide output voltage range: 0.8V to 24V

• Synchronous rectification with up to 95% efficiency

• Low 95ns minimum on-time for high step-down ratio

• DCR or RSENSE current sensing

• Selectable low ripple Burst Mode® operation, pulse skipping, or continuous operation

• Selectable fixed operating frequency in 50kHz to 900kHz range

• PLL synchronizable operating frequency in 75kHz to 850kHz range

• Current mode control for fast transient response & easy loop compensation

• Adjustable soft start or tracking

• Output overvoltage & overcurrent foldback protection

• Extended & industrial grade: –40°C to 125°C operating junction temperature

• Automotive temperature grade: –40°C to 150°C operating junction temperature

• Military temperature grade: –55°C to 150°C operating junction temperature