LM5146-Q1

• AEC-Q100 qualified for automotive applications:
  • Device temperature grade 1: –40°C to +125°C ambient temperature range
• Functional Safety-Capable
  • Documentation available to aid functional safety system design
• Versatile synchronous buck DC/DC controller
  • Wide input voltage range of 5.5 V to 100 V
  • 150°C maximum junction temperature
  • 0.8-V reference with ±1% feedback accuracy
  • Adjustable output voltage from 0.8 V to 60 V
  • 40-ns t_ON(min) for high V_IN / V_OUT ratio
  • 140-ns t_OFF(min) for low dropout
  • Lossless R_DS(on) or shunt current sensing
  • Optimized for CISPR 25 Class 5 requirements
• Switching frequency from 100 kHz to 1 MHz
  • SYNC In and SYNC Out capability
  • Selectable diode emulation or FPWM
• 7.5-V gate drivers for standard V_TH MOSFETs
  • 14-ns adaptive dead-time control
  • 2.3-A source and 3.5-A sink capability
• Inherent protection features for robust design
  • Adjustable output voltage soft start
  • Hiccup-mode overcurrent protection
  • Input UVLO with hysteresis
  • VCC and gate-drive UVLO protection
  • Precision enable input and open-drain PGOOD indicator for sequencing and control
  • Thermal shutdown protection with hysteresis
• 20-pin VQFN package with wettable flanks
• Create a custom design using the LM5146-Q1 with WEBENCH Power Designer

The LM5146-Q1 100-V synchronous buck controller regulates from a high input voltage source or from an input rail subject to high voltage transients, minimizing the need for external surge suppression components. A high-side switch minimum on-time of 40 ns gives large step-down ratios, enabling the direct step-down conversion from a 48-V nominal input to low-voltage rails for reduced system complexity and solution cost. The LM5146-Q1 continues to operate during input voltage dips as low as 5.5 V, at nearly 100% duty cycle if needed, making it an excellent choice for high-performance 48-V battery automotive applications, ADAS (surround view ECU) and HEV/EV systems.

Forced-PWM (FPWM) operation eliminates switching frequency variation to minimize EMI, while user-selectable diode emulation lowers current consumption at light-load conditions. The adjustable switching frequency as high as 1 MHz can be synchronized to an external clock source to eliminate beat frequencies in noise-sensitive applications