LT8648S Datasheet

• Silent Switcher^®2 Architecture
  • Ultralow EMI Emissions on Any PCB
  • Eliminates PCB Layout Sensitivity
  • Internal Bypass Capacitors Reduce Radiated EMI
  • Optional Spread Spectrum Modulation
• High Efficiency at High Frequency
  • Up to 95.5% Efficiency at 1MHz, 12V_IN to 5V_OUT
  • Up to 93% Efficiency at 2MHz, 12V_IN to 5V_OUT
• Wide Input Voltage Range: 3V to 42V
• 15A Output Current
• Low Quiescent Current Burst Mode^® Operation
  • 100μA I_Q Regulating 12V_IN to 5V_OUT
  • Output Ripple < 10mV_P-P
• External Compensation: Fast Transient Response and Current Sharing
• Fast Minimum Switch On-Time: 25ns
• Low Dropout Under All Conditions: 35mV at 1A
• Forced Continuous Mode
• Adjustable and Synchronizable: 200kHz to 2.2MHz
• Output Soft-Start and Power Good
• Safely Tolerates High Reverse Current
• 36-Lead 7mm × 4mm LQFN Package (LT8648S)
• AEC-Q100 Qualified for Automotive Applications

• Automotive and Industrial Supplies
• General Purpose Step-Down

The LT^®8648S synchronous step-down regulator features second generation Silent Switcher architecture designed to minimize EMI emissions while delivering high efficiency at high switching frequencies. This includes the integration of input and boost capacitors to optimize all the fast current loops inside and make it easy to achieve advertised EMI performance by reducing layout sensitivity. This performance makes the LT8648S ideal for noise sensitive applications and environments.

The fast, clean, low overshoot switching edges enable high efficiency operation even at high switching frequencies, leading to a small overall solution size. Peak current mode control with a 25ns minimum on-time allows high step down ratios even at high switching frequencies. External compensation via the VC pin allows for fast transient response at high switching frequencies. The VC pin also enables current sharing and a CLKOUT pin enables synchronizing other regulators to the LT8648S.

Burst Mode operation enables low standby current consumption, forced continuous mode can control frequency harmonics across the entire output load range, or spread spectrum operation can further reduce EMI emissions.