LT3437IDD#TRPBF

The LT3437 is a 200kHz monolithic buck switching regulator that accepts input voltages up to 80V. A high efficiency 500mA, 0.8Ω switch is included on the die along with all the necessary oscillator, control and logic circuitry. Current mode topology is used for fast transient response and good loop stability. Innovative design techniques along with a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by employing Burst Mode operation at low currents, utilizing the output to bias the internal circuitry, and by using a supply boost capacitor to fully saturate the power switch. Burst Mode operation can be defeated by a logic high signal on the SYNC pin which results in lower light load ripple at the expense of light load efficiency. Patented circuitry maintains peak switch current over the full duty cycle range. Shutdown reduces input supply current to less than 1μA. External synchronization can be implemented by driving the SYNC pin with logic-level inputs. A single capacitor from the CSS pin to the output provides a controlled output voltage ramp (soft-start). The LT3437 is available in a low profile (0.75mm) 3mm × 3mm 10-pin DFN package or a 16-Pin TSSOP Package, both with exposed pad leadframes for low thermal resistance.

Applications

• High Voltage Power Conversion
• 14V and 42V Automotive Systems
• Industrial Power Systems
• Distributed Power Systems
• Battery-Powered Systems
• Powered Ethernet

Key features

• Wide Input Range: 3.3V to 60V
• Load Dump (Input Transient) Protection to 80V
• 500mA Peak Switch Current
• Burst Mode Operation: 100μA Quiescent Current
• Low Shutdown Current: l0 < 1μA
• Defeatable Burst Mode Operation
• 200kHz Switching Frequency
• Saturating Switch Design: 0.8Ω On-Resistance
• Peak Switch Current Maintained Over Full Duty Cycle Range
• 1.25V Feedback Reference Voltage
• Easily Synchronizable
• Soft-Start Capability
• Small 10-Pin Thermally Enhanced DFN Package