Overview
Features and Benefits
- 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 96% Efficiency at 1MHz, 12VIN to 3.3VOUT
- Up to 95% Efficiency at 2MHz, 12VIN to 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® Operation
- 240µA IQ Regulating 12VIN to 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
Product Details
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 VC pin 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.
APPLICATIONS
- Server Power Applications
- Automotive and Industrial Supplies
- General Purpose Step-Down
Product Categories
Markets and Technologies
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
Documentation & Resources
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DC2560A - Demo Manual (Rev. A)7/17/2018PDF421 K
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NEW
Revolutionizing Wireless Coverage: The Power of Cellular DAS Integrated Solutions5/1/2023 Analog Dialogue
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Comprehensive Power Supply System Designs for Harsh Automotive Environments Consume Minimal Space, Preserve Battery Charge, Feature Low EMI8/16/2019 Analog Dialogue
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Tiny, High Efficiency Monolithic Regulators Power Advanced SoCs and Microprocessors Feature Silent Switcher 2 Technology for Low EMI10/29/2018
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Tiny, High Efficiency Monolithic Regulators Power Advanced SoCs and μProcessors, Feature Silent Switcher 2 Technology for Low EMI8/17/2018 LT Journal
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
LT8642-1
LT8642S
LTpowerCAD
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
To open the project file for this circuit:
Step 1: Download and install LTpowerCAD on your computer.
Step 2: Click on the link(s) in the section below to download part-specific project files.
Step 3: If the project file doesn't run, right-click the link and select "Save Target As." Then start the LTpowerCAD tool and open the project file by selecing "Open Project" from the "File" menu.
LTpowerCAD Project Files
Design tools for the following parts are available in LTpowerCAD:
LT8642S
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.
| Part Number | Material Declaration | Reliability Data | Pin/Package Drawing | CAD Symbols, Footprints & 3D Models |
|---|---|---|---|---|
| LT8642SEV#PBF | Material Declaration | Reliability Data | 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP) | |
| LT8642SIV#PBF | Material Declaration | Reliability Data | 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP) | |
| Wafer Fabrication Data |
PCN-PDN Information
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Sample & Buy
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Buy Now Pricing
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List Pricing
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Lead Times
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Sampling
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Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.