1 Features
1• High Efficiency at Light Loads with Pulse Skipping
Eco-mode™
• 92-mΩ High-Side MOSFET
• 146 μA Operating Quiescent Current and
2 μA Shutdown Current
• 100 kHz to 2.5 MHz Fixed Switching Frequency
• Synchronizes to External Clock
• Low Dropout at Light Loads with Integrated BOOT
Recharge FET
• Adjustable UVLO Voltage and Hysteresis
• 0.8 V 1% Internal Voltage Reference
• 8-Terminal HSOP with PowerPAD™ Package
• –40°C to 150°C TJ Operating Range
• Create a Custom Design using the TPS54540 with
the WEBENCH® Power Designer

2 Applications
• Industrial Automation and Motor Control
• Vehicle Accessories: GPS, Entertainment
• USB Dedicated Charging Ports and Battery
Chargers
• 12 V and 24 V Industrial, Automotive and
Communications Power Systems

3 Description
The TPS54540 is a 42 V, 5 A, step down regulator
with an integrated high side MOSFET. The device
survives load dump pulses up to 45V per ISO 7637.
Current mode control provides simple external
compensation and flexible component selection. A
low ripple pulse skip mode reduces the no load
supply current to 146 μA. Shutdown supply current is
reduced to 2 μA when the enable pin is pulled low.
Undervoltage lockout is internally set at 4.3 V but can
be increased using the enable pin. The output voltage
start up ramp is internally controlled to provide a
controlled start up and eliminate overshoot.
A wide switching frequency range allows either
efficiency or external component size to be optimized.
Output current is limited cycle-by-cycle. Frequency
foldback and thermal shutdown protects internal and
external components during an overload condition.
The TPS54540 is available in an 8-terminal thermally
enhanced HSOP PowerPAD™ package.