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LTC7821: Hybrid Step-Down Synchronous Controller Data Sheet (Rev. A)11/21/2017PDF1 M
Alternative Parts
Overview
Features and Benefits
- Wide VIN Range: 10V to 72V (80V ABS Max)
- Soft Switching for Low Noise Operation
- Phase-Lockable Fixed Frequency 200kHz to 1.5MHz
- ±1% Output Voltage Accuracy
- RSENSE or DCR Current Sensing
- Programmable CCM, DCM, or Burst Mode® Operation
- CLKOUT Pin for Multiphase Operation
- Short Circuit Protected
- EXTVCC Input for Improved Efficiency
- Monotonic Output Voltage Start-Up
- Optional External Reference
- 32-Pin (5mm × 5mm) QFN
Product Details
The LTC7821 uses a proprietary architecture that merges a soft switching charge pump topology with a synchronous step-down converter to provide superior efficiency and EMI performance compared to traditional switching architectures.
In a typical 48V to 12V application, efficiency of greater than 97% is attainable with the LTC7821 switching at 500kHz. The same efficiency can only be achieved with a traditional controller switching at one-third the frequency. Higher switching frequencies allow the use of smaller inductances that yield faster transient response and smaller solution size.
The LTC7821 can be easily paralleled to provide higher output currents with its accurate current sharing capability and frequency synchronization function.
Applications
- Intermediate Bus Converters
- High Current Distributed Power Systems
- Telecom, Datacom, and Storage Systems
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 (3)
Documentation & Resources
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R526 Reliability Data3/26/2018PDF365 K
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DC2513B - Demo Manual (Rev. 0)7/31/2020PDF798 K
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DC2787A - Demo Manual12/6/2019PDF1M
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DC2513A - Demo Board Manual12/7/2017PDF686K
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80V to 150V Non-Isolated DC/DC2/6/2018PDF661K
Tools & Simulations
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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 |
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LTC7821EUH#PBF | Material Declaration | Reliability Data | 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP) | |
LTC7821EUH#TRPBF | Material Declaration | Reliability Data | 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP) | |
LTC7821IUH#PBF | Material Declaration | Reliability Data | 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP) | |
LTC7821IUH#TRPBF | Material Declaration | Reliability Data | 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP) | |
Wafer Fabrication Data | R526 Reliability Data |
PCN-PDN Information
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Support & Discussions
LTC7821 Discussions
Sample & Buy
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Evaluation Boards
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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.