Features and Benefits
- Single Inductor Allows VIN Above, Below, or Equal to Regulated VOUT
- VIN Range 2.8V (Need EXTVCC > 6.4V) to 80V
- VOUT Range: 1.3V to 80V
- Quad N-Channel MOSFET Gate Drivers
- Synchronous Rectification: Up to 98% Efficiency
- Input and Output Current Monitor Pins
- Synchronizable Fixed Frequency: 100kHz to 400kHz
- Integrated Input Current, Input Voltage, Output Current and Output Voltage Feedback Loops
- Improved Light Load Transition from DCM to FCM
- Improved IMON_OUT, IMON_IN Offset When Cold
- Clock Output Usable To Monitor Die Temperature
The LT8705A is a high performance buck-boost switching regulator controller that operates from input voltages above, below or equal to the output voltage. The part has integrated input current, input voltage, output current and output voltage feedback loops. With a wide 2.8V to 80V input and 1.3V to 80V output range, the LT8705A is compatible with most solar, automotive, telecom and battery-powered systems. The LT8705A is an improved pin compatible version of the LT8705 and is recommended for new designs. See LT8705A vs LT8705 in the Applications Information section for more information.
The LT8705A includes a MODE pin to select among Burst Mode® operation, discontinuous or continuous conduction mode at light loads. Additional features include a 3.3V/12mA LDO, a synchronizable fixed operating frequency, and onboard gate drivers.
|LT8705A||Improved, pin-to-pin compatible version of LT8705. Recommended for all new designs|
- High Voltage Buck-Boost Converters
- Input or Output Current Limited Converters
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)
Demonstration circuit 2285A features two high power high performance buck-boost LT8705A converters operating in master-slave configuration. The circuit can operate with input voltages above, below or equal to the output voltage. The demo board input range is 36V to 75V. The output is optimized for 48V at 18A, with the output current limit set at 20A. The circuit will operate with lower input voltage than 36V if load current is reduced.
Tools & Simulations
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.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
Models for the following parts are available in LTspice:
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.
Design tools for the following parts are available in LTpowerCAD:
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.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.