Features and Benefits
- Accurate Input/Output Current Control: ±5% Over Temperature
- Accurate Output Voltage Control: ±1%
- Wide VIN Range: 1.6V to 18V
- 1.4MHz Switching Frequency
- High Output Voltage: Up to 35V
- Low VCESAT Switch: 200mV at 1A
- Available in (3mm x 3mm x 0.8mm) 10-Pin DFN and 10-Pin MSOP Packages
The LT1618 step-up DC/DC converter combines a traditional voltage feedback loop and a unique current feedback loop to operate as a constant-current, constant-voltage source. This fixed frequency, current mode switcher operates from a wide input voltage range of 1.6V to 18V, and the high switching frequency of 1.4MHz permits the use of tiny, low profile inductors and capacitors. The current sense voltage is set at 50mV and can be adjusted using the IADJ pin.
Available in the 10-Pin (3mm x 3mm) Exposed Pad DFN and 10-pin MSOP packages, the LT1618 provides a complete solution for constant-current applications.
- LED Backlight Drivers
- USB Powered Boost/SEPIC Converters
- Input Current Limited Boost/SEPIC Converters
- Battery Chargers
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 780B is a Constant-Current Constant- Voltage 1.4MHz Step-up DC/DC Converter featuring the LT1618. DC780B demonstrates a general purpose Boost converter with a 12V, 250mA output from a 3.3V-4.2V source.
The demo board can also be used as an LED driver, where a Luxeon LED (not installed), is driven with a regulated current of 500mA (default current), at a forward voltage of 3.5V. By changing the value or R4 to 2.2M the LED current can be regulated at 250mA.
The LT1618 can be used for wider input voltages, but output voltage level and component selection restrict this demo circuit to Lithium Ion battery input levels.
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:
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.