TI LM5143RHAR

The LM5143 is a 65V synchronous buck DC/DC controller for high-current single or dual outputs. Derived from a wide VIN range controller family, the device employs an interleaved stackable peak current mode control architecture that delivers simple loop compensation, fast transient response, excellent load and line regulation, and precise current sharing via paralleled phases for high output current. The 65 ns high-side switch ultra-short on-time enables high step-down ratios, supporting direct conversion from 12V, 24V, or 48V inputs to low-voltage rails, reducing system complexity and cost. The LM5143 continues to operate at near 100% duty cycle as required when input voltage drops to 3.5V.

A 15 μA no-load quiescent current with regulated output voltage extends battery-powered system operating time. Powering the LM5143 from the switching regulator output or another available supply enables lower input quiescent current and power dissipation.

CISPR 11 and CISPR 32 EMI requirements are easily met through a comprehensive set of features. Adaptive timing high-current MOSFET gate drivers with adjustable slew rate control minimize body diode conduction during switching transitions, reducing switching losses and improving thermal and EMI performance at high input voltages and high switching frequencies. 180° interleaved operation for the two outputs reduces input capacitor ripple current and EMI filter size. A 90° out-of-phase clock output is available for cascaded, multi-channel, or multiphase power stages. Resistor-adjustable switching frequency up to 2.2 MHz can be synchronized to an external clock source up to 2.5 MHz, eliminating beat frequencies in noise-sensitive applications. Optional triangle spread-spectrum modulation further improves the EMI signature.

Additional features of the LM5143 include a 150°C maximum operating junction temperature, user-selectable diode emulation for reduced current consumption under light-load conditions, configurable soft-start, an open-drain power-good flag for fault reporting and output monitoring, independent enable inputs, monotonic start-up into pre-biased loads, an integrated VCC bias supply regulator with automatic switchover to an external bias connected at VCCX, programmable hiccup mode overload protection, and thermal shutdown with auto-recovery. Inductor DCR current sensing achieves ultra-high efficiency, while shunt resistor sensing is available for high accuracy.

The LM5143 controller is available in a 6mm×6mm thermally enhanced 40-pin VQFN package. Wide input voltage range, low quiescent current consumption, high-temperature operation, cycle-by-cycle current limiting, low EMI signature, and compact solution size make it an ideal point-of-load regulator solution for applications requiring enhanced reliability and durability.

• Wide input voltage range: 3.5V to 65V
• 1% accuracy, 3.3V/5V fixed or 0.6V to 55V adjustable output voltage
• 150°C maximum junction temperature
• 4μA typical shutdown mode current
• 15μA typical no-load standby current
• Two interleaved synchronous buck channels
• Dual-channel or single-output multiphase
• 65 ns tON(min) for high VIN/VOUT ratio
• 60 ns tOFF(min) for low dropout
• Shunt or inductor DCR current sensing
• Discontinuous mode overcurrent protection
• Independent enable and PGOOD functions
• Adjustable output voltage soft-start
• VCC, VDDA, and gate drive UVLO protection
• Thermal shutdown with hysteresis
• Optimized for CISPR 11 and CISPR 32 Class B conducted and radiated EMI requirements
• Slew-rate-controlled adaptive gate driver
• Spread spectrum for reduced peak emissions
• 100 kHz to 2.2 MHz switching frequency
• Sync input and sync output functions
• Selectable diode emulation or FPWM mode

• Communications Systems: Wireless Infrastructure, Remote Radio Units (RRU)
• Industrial: Factory Automation and Control, Robotics
• Enterprise Systems: High-Performance Computing