Features and Benefits
- Wide Input Range: 5V to 42V
- Low Dropout Under All Conditions: 450mV at 2.1A
- Accurate 5V Output: ±1.3% Over Full Temperature Range
- Programmable Cable Drop Compensation
- Programmable Output Current Limit
- Output Current Monitor
- Dual Input Feedback Permits Regulation on Output of USB Switch
- Forced Continuous Mode for Fast Load Step Response
- High Efficiency Synchronous Operation at 2MHz:
- 93% Efficiency at 2.1A, 5VOUT from 12VIN
- 95% Efficiency at 0.9A, 5VOUT from 12VIN
- Fast Minimum Switch-On Time: 45ns
- Adjustable Output from 5.0V to 5.25V
- Adjustable and Synchronizable: 300kHz to 2.2MHz
- Small Thermally Enhanced 3mm × 5mm 24-Lead QFN Package
The LT8697 is a compact, high efficiency, high speed synchronous monolithic step-down switching regulator designed to power 5V USB applications. A precise output voltage and programmable cable drop compensation maintain accurate 5V regulation at the USB socket connected to the end of a long cable. Forced continuous operation allows the LT8697 to sink current, further enhancing accurate 5V regulation during load transients.
Accurate and programmable output current limit, a power good indicator pin and an output current monitor pin improve system reliability and safety, allow the user to implement latch-off or auto-retry functionality and can eliminate the need for a USB switch IC. Dual feedback allows regulation on the output of a USB switch and limits cable drop compensation to a maximum of 5.8V output, protecting USB devices during fault conditions. Thermal shutdown provides additional protection by limiting power dissipation in the IC during an overtemperature fault.
The LT8697 is available in a small 24-lead 3mm × 5mm package with an exposed pad for low thermal resistance.
- Automotive and Industrial USB
- Precision 5V Supply
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 1973A is a USB 5V 2.5A output, 6V to 42V input synchronous buck with cable drop compensation featuring the LT8697. The LT8697 is a compact, high efficiency, high speed synchronous monolithic step-down switching regulator designed to power 5V USB applications. A precise output voltage and programmable cable drop compensation maintain accurate 5V regulation at the USB socket at the end of a long cable. The circuit runs at 2MHz to minimize external components size and to avoid AM band.
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:
LT8697 Companion Parts
Recommended Related Parts
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.