LT8642S Series

18V, 10A Synchronous Step-Down Silent Switcher 2

Catalog

18V, 10A Synchronous Step-Down Silent Switcher 2

Part	Output Type	Number of Outputs	Output Configuration	Mounting Type	Supplier Device Package	Voltage - Input (Max) [Max]	Voltage - Output (Min/Fixed)	Frequency - Switching [Min]	Frequency - Switching [Max]	Voltage - Output (Max) [Max]	Voltage - Input (Min) [Min]	Current - Output	Synchronous Rectifier	Function	Topology	Package / Case	Operating Temperature [Min]	Operating Temperature [Max]
Analog Devices LT8642SIV#PBF	Adjustable	1	Positive	Surface Mount	24-LQFN (4x4)	18 V	0.597 V	200 kHz	3 MHz	3.3 V	2.8 V	10 A		Step-Down	Buck	24-TFQFN Exposed Pad	-40 °C	125 ¯C
Analog Devices LT8642EV-1#TRPBF	Adjustable	1	Positive	Surface Mount	20-LQFN (3x4)	18 V	0.6 V	200 kHz	3 MHz	18 V	2.5 V	10 A		Step-Down	Buck	20-TFQFN Exposed Pad	-40 °C	125 ¯C

Catalog

18V, 10A Synchronous Step-Down Silent Switcher 2

Key Features

• Silent Switcher®2 ArchitectureUltralow EMI Emissions On Any PCBEliminates PCB Layout SensitivityInternal Bypass Capacitors Reduce Radiated EMIOptional Spread Spectrum Modulation

• Ultralow EMI Emissions On Any PCB

• Eliminates PCB Layout Sensitivity

• Internal Bypass Capacitors Reduce Radiated EMI

• Optional Spread Spectrum Modulation

• High Efficiency at High FrequencyUp to 96% Efficiency at 1MHz, 12VINto 3.3VOUTUp to 95% Efficiency at 2MHz, 12VINto 3.3VOUT

• Up to 96% Efficiency at 1MHz, 12VINto 3.3VOUT

• Up to 95% Efficiency at 2MHz, 12VINto 3.3VOUT

• Wide Input Voltage Range: 2.8V to 18V

• 10A Output Current

• External Compensation: Fast Transient Response and Current Sharing

• Low Quiescent Current Burst Mode®Operation240µA IQ Regulating 12VINto 1.2VOUTOutput Ripple < 10mVP-P

• 240µA IQ Regulating 12VINto 1.2VOUT

• Output Ripple < 10mVP-P

• Fast Minimum Switch On-Time: 25ns

• Low Dropout Under All Conditions: 50mV at 1A

• Forced Continuous Mode

• Adjustable and Synchronizable: 200kHz to 3MHz

• Output Soft-Start and Power Good

• Small 24-Lead 4mm × 4mm LQFN Package

Description

The LT8642S 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 bypass capacitors to optimize all the fast current loops inside and make it easy to achieve advertised EMI performance by eliminating layout sensitivity.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 20ns minimum on-time allows high step down ratios even at high switching frequencies. External compensation via the VCpin allows for fast transient response at high switching frequencies. A CLKOUT pin enables synchronizing other regulators to the LT8642S.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. Soft-start and tracking functionality is accessed via the SS pin, and an accurate input voltage UVLO threshold can be set using the EN/UV pin.APPLICATIONSServer Power ApplicationsAutomotive and Industrial SuppliesGeneral Purpose Step-Down