LM5148RGYR

The LM5148 is a 80-V, ultra-low IQ synchronous buck DC/DC controller for high-current, single-output applications. The controller uses a peak current-mode control architecture for easy loop compensation, fast transient response, and excellent load and line regulation. The LM5148 can be set up in idual-phase mode (paralleled output) with accurate current sharing for high-current applications. It can operate at input voltages as low as 3.5 V, at nearly 100% duty cycle if needed. The LM5148 has a unique EMI reduction feature known as dual random spread spectrum (DRSS). Combining low-frequency triangular and high-frequency random modulations mitigates EMI disturbances across lower and higher frequency bands, respectively. This hybrid technique aligns with the multiple resolution bandwidth (RBW) settings specified in industry-standard EMC tests. Additional features of the LM5148 include 150°C maximum junction temperature operation, user-selectable diode emulation for lower current consumption at light-load conditions, open-drain power-good flag for fault reporting and output monitoring, precision enable input, monotonic start-up into prebiased load, integrated VCC bias supply regulator, internal 3-ms soft-start time, and thermal shutdown protection with automatic recovery. The LM5148 controller comes in a 3.5-mm×5.5-mm thermally enhanced, 24-pin VQFN package.

Applications

• Building automation
• Industrial transport
• Power delivery
• Test and measurement

Key features

• Functional Safety-Capable Documentation available to aid functional safety system design
• Selectable dual random spread spectrum (DRSS) feature for enhanced EMI performance across low and high-frequency bands Optimized for CISPR 32 Class B requirements
• Versatile synchronous buck DC/DC controller
• Wide input voltage range of 3.5 V to 80 V
• 1% accurate, fixed 3.3 V, 5 V, 12 V, or adjustable output from 0.8 V to 55 V
• 150°C maximum junction temperature
• Lossless DCR or shunt current sensing
• Shutdown mode current of 2.3 μA
• No-load sleep current of 9.5 μA
• Internal soft-start ramp of 3 ms
• Stackable up to two phases
• Internal bootstrap diode
• Switching frequency from 100 kHz to 2.2 MHz
• SYNC in and SYNC out capability
• Selectable PFM or FPWM modes
• Inherent protection features for robust design
• Internal hiccup mode overcurrent protection
• ENABLE and PGOOD functions
• VCC, VDDA, and gate-drive UVLO protection
• Internal or external loop compensation
• Thermal shutdown protection with hysteresis
• Create a custom design using the LM5148 with WEBENCH Power Designer