1. Products
  2. Power Management
  3. Switching Regulators
  4. Step-Down (Buck) Regulators
  5. Internal Power Switch Buck Regulators
  6. LT1578


Features and Benefits

  • 1.5A Switch Current
  • High Efficiency—Low Loss 0.2Ω Switch
  • Constant 200kHz Switching Frequency
  • 4V to 15V Input Voltage Range
  • Minimum Output: 1.21V
  • Low Supply Current: 1.9mA
  • Low Shutdown Current: 20µA
  • Easily Synchronizable Up to 400kHz
  • Cycle-by-Cycle Current Limit
  • Reduced EMI Generation
  • Low Thermal Resistance SO-8 Package
  • Uses Small Low Value Inductors

Product Details

The LT1578 is a 200kHz monolithic buck mode switching regulator. A 1.5A switch is included on the die along with all the necessary oscillator, control and logic circuitry. The topology is current mode for fast transient response and good loop stability. The LT1578 is a modified version of the LT1507 that has been optimized for noise sensitive applications. It will operate over a 4V to 15V input range.

In addition, the reference voltage has been lowered to allow the device to produce output voltages down to 1.2V. Quiescent current has been reduced by a factor of two. Switch on resistance has been reduced by 30%. Switch transition times have been slowed to reduce EMI generation. The oscillator frequency has been reduced to 200kHz to maintain high efficiency over a wide output current range.

The pinout has been changed to improve PC layout by allowing the high current, high frequency switching circuitry to be easily isolated from low current, noise sensitive control circuitry. The new SO-8 package includes a fused ground lead that significantly reduces the thermal resistance of the device to extend the ambient operating temperature range. Standard surface mount external parts can be used including the inductor and capacitors.


  • Portable Computers
  • Battery-Powered Systems
  • Battery Charger
  • Distributed Power Systems

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Evaluation Kits (1)

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
LT1578CS8#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1578CS8#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1578CS8-2.5#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1578CS8-2.5#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1578IS8#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1578IS8#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1578IS8-2.5#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1578IS8-2.5#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
Wafer Fabrication Data R388 Reliability Data

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Buy Now Pricing

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List Pricing

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Lead Times

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