Overview
Features and Benefits
- Wide Input Voltage Range: 3.5V to 30V
- Low Quiescent Current: 7mA
- Internal 8A Switch (10A for LT1270A)
- Very Few External Parts Required
- Self-Protected Against Overloads
- Shutdown Mode Draws Only 100µA Supply Current
- Flyback-Regulated Mode Has Fully Floating Outputs
- Can be Externally Synchronized
(See LT1072 Data Sheet) - Comes in Standard 5-Pin TO-220 Package
Product Details
The LT1270A/LT1270 are monolithic high power switching regulators. Identical to the popular LT1070, except for switching frequency (60kHz) and higher switch current, they can be operated in all standard switching configurations including buck, boost, flyback, and inverting. A high current, high efficiency switch is included on the die along with all oscillator, control, and protection circuitry. Integration of all functions allows the LT1270A/LT1270 to be built in a standard TO-220 power package. This makes it extremely easy to use and provides “bust proof” operation similar to that obtained with 3-pin linear regulators.
The LT1270A/LT1270 operate with supply voltages from 3.5V to 30V, and draw only 7mA quiescent current. By utilizing current-mode switching techniques, they provide excellent AC and DC load and line regulation.
The LT1270A/LT1270 use adaptive anti-sat switch drive to allow very wide ranging load currents with no loss in efficiency. An externally activated shutdown mode reduces total supply current to 100mA typical for standby operation.
Applications
- High Efficiency Buck Converter
- PC Power Supply with Multiple Outputs
- Battery Upconverter
- Negative-to-Positive Converter
User Note: This data sheet is only intended to provide specifications, graphs and a general functional description of the LT1270A/LT1270. Application circuits are included to show the capability of the LT1270A/LT1270. A complete design manual (AN-19) should be obtained to assist in developing new designs. AN-19 contains a comprehensive discussion of both the LT1070 and the external components used with it, as well as complete formulas for calculating the values of these components. AN-19 can also be used for the LT1270A/LT1270 by factoring in the higher switch current rating and higher operating frequency.
A comprehensive CAD program called SwitcherCad is also available. Contact the local sales office in your area or the factory direct.
Product Categories
Product Lifecycle
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)
Documentation & Resources
-
R012 Reliability Data3/23/2018
-
DC297A - Demo Manual9/24/2009
Tools & Simulations
LTspice
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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 |
---|---|---|---|---|
LT1270ACT#06PBF | Material Declaration | Reliability Data | 5-Lead TO-220 (Flow 06) | |
LT1270ACT#PBF | Material Declaration | Reliability Data | 5-Lead TO-220 | |
LT1270CT#PBF | Material Declaration | Reliability Data | 5-Lead TO-220 | |
Wafer Fabrication Data | R012 Reliability Data |
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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.