Packaging information
| Package | Pins VQFN (RGY) | 20 |
| Operating temperature range (°C) -40 to 125 |
| Package qty | Carrier 3,000 | LARGE T&R |
Features for the LM5145
- Versatile synchronous buck DC/DC controller
- Wide input voltage range of 6 V to 75 V
- 0.8-V reference with ±1% feedback accuracy
- Adjustable output voltage from 0.8 V to 60 V
- 40-ns tON(min) for high VIN / VOUT ratio
- 140-ns tOFF(min) for low dropout
- Optimized for CISPR 32 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 VTH MOSFETs
- 14-ns adaptive dead-time control
- 2.3-A source and 3.5-A sink capability
- Low-side soft start for prebiased start-up
- Fast line and load transient response
- Voltage-mode control with line feedforward
- High gain-bandwidth error amplifier
- 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 LM5145 with WEBENCH Power Designer
Description for the LM5145
The LM5145 75-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 LM5145 continues to operate during input voltage dips as low as 6 V, at nearly 100% duty cycle if needed, making it an excellent choice for high-performance industrial control, robotic, datacom, and RF power applications.
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.