FEATURES
• Emulated Peak Current Mode
• Wide Operating Range Up to 80 V
• Low IQ Shutdown (< 10 μA)
• Drives Standard or Logic Level MOSFETs
• Robust 3.5-A Peak Gate Drive
• Free-Run or Synchronous Operation to 1 MHz
• Optional Diode Emulation Mode
• Programmable Output from 1.215 V to 80 V
• Precision 1.5% Voltage Reference
• Programmable Current Limit
• Programmable Soft-Start
• Programmable Line Under-Voltage Lockout
• Automatic Switch to External Bias Supply

SUPPORTS EXTREME TEMPERATURE
APPLICATIONS
• Controlled Baseline
• One Assembly and Test Site
• One Fabrication Site
• Available in Extreme (–55°C to 175°C)
Temperature Range
• Extended Product Life Cycle
• Extended Product-Change Notification
• Product Traceability
• Texas Instruments' high temperature products
utilize highly optimized silicon (die) solutions with design and process enhancements to
maximize performance over extended
temperatures.

APPLICATIONS
• Down-Hole Drilling
• High Temperature Environments

DESCRIPTION
The LM5116 is a synchronous buck controller intended for step-down regulator applications from a high voltage
or widely varying input supply. The control method is based upon current mode control utilizing an emulated
current ramp. Current mode control provides inherent line feed-forward, cycle by cycle current limiting and ease
of loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width
modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications.
The operating frequency is programmable from 50 kHz to 1 MHz. The LM5116 drives external high-side and lowside
NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables
discontinuous mode operation for improved efficiency at light load conditions. A low quiescent current shutdown
disables the controller and consumes less than 10 μA of total input current. Additional features include a high
voltage bias regulator, automatic switch-over to external bias for improved efficiency, thermal shutdown,
frequency synchronization, cycle by cycle current limit and adjustable line under-voltage lockout.