LM5122MH/NOPB LM5122MHX/NOPB Power Regulator IC Switching Controllers Wide Input Sync Boost Controller

1 Features

• Maximum Input Voltage: 65 V

• Minimum Input Voltage: 3 V (4.5 V for Start-Up)

• Output Voltage up to 100 V

• Bypass (VOUT = VIN) Operation

• 1.2-V Reference with ±1% Accuracy

• Free-Run and Synchronizable Switching to 1 MHz

• Peak-Current-Mode Control

• Robust 3-A Integrated Gate Drivers

• Adaptive Dead-Time Control

• Optional Diode-Emulation Mode

• Programmable Cycle-by-Cycle Current Limit

• Hiccup-Mode Overload Protection

• Programmable Line UVLO

• Programmable Soft Start

• Thermal Shutdown Protection

• Low Shutdown Quiescent Current: 9 μA

• Programmable Slope Compensation

• Programmable Skip-Cycle Mode Reduces Standby Power

• Allows External VCC Supply

• Inductor DCR Current Sensing Capability

• Multi-phase Capability

• Thermally Enhanced 20 or 24-Pin HTSSOP

• Create a Custom Design Using the LM5122 With the WEBENCH® Power Designer

2 Applications

• 12-V, 24-V, and 48-V Power Systems • Automotive Start-Stop
• Audio Power Supply
• High-Current Boost Power Supply

3 Description

The LM5122 is a multi-phase capable synchronous boost controller intended for high-efficiency synchronous boost regulator applications. The control method is based upon peak-current-mode control. Current-mode control provides inherent line feed forward, cycle-by-cycle current limiting, and ease of loop compensation.

The switching frequency is programmable up to 1 MHz. Higher efficiency is achieved by two robust N- channel MOSFET gate drivers with adaptive dead- time control. A user-selectable diode-emulation mode also enables discontinuous-mode operation for improved efficiency at light load conditions.

An internal charge pump allows 100% duty cycle for high-side synchronous switch (bypass operation). A 180° phase shifted clock output enables easy multi- phase interleaved configuration. Additional features include thermal shutdown, frequency synchronization, hiccup-mode current limit, and adjustable line undervoltage lockout.

Device Information