Features and Benefits
- Uses Tiny Capacitors and Inductor
- Internally Compensated
- Fixed Frequency 1.4MHz Operation
- Operates with VIN as Low as 1.1V
- 3V at 30mA from a Single Cell
- 5V at 200mA from 3.3V Input
- 15V at 60mA from Four Alkaline Cells
- High Output Voltage: Up to 34V
- Low Shutdown Current: <1µA
- Low VCESAT Switch: 300mV at 300mA
- 5-Lead SOT-23 Package
The LT1613 is the industry’s first 5-lead SOT-23 current mode DC/DC converter. Intended for small, low power applications, it operates from an input voltage as low as 1.1V and switches at 1.4MHz, allowing the use of tiny, low cost capacitors and inductors 2mm or less in height. Its small size and high switching frequency enables the complete DC/DC converter function to take up less than 0.2 square inches of PC board area. Multiple output power supplies can now use a separate regulator for each output voltage, replacing cumbersome quasi-regulated approaches using a single regulator and a custom transformer.
A constant frequency, internally compensated current mode PWM architecture results in low, predictable output noise that is easy to filter. The high voltage switch on the LT1613 is rated at 36V, making the device ideal for boost converters up to 34V as well as for Single-Ended Primary Inductance Converter (SEPIC) and flyback designs. The device can generate 5V at up to 200mA from a 3.3V supply or 5V at 175mA from four alkaline cells in a SEPIC design.
The LT1613 is available in the 5-lead SOT-23 package.
- Digital Cameras
- Cordless Phones
- Battery Backup
- LCD Bias
- Medical Diagnostic Equipment
- Local 5V or 12V Supply
- External Modems
- PC Cards
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)
The LT1611 and LT1613 are 5-lead SOT-23, current mode DC/DC converters. Intended for small, low power applications, both operate from inputs as low as 1V and switch at 1.4MHz, allowing the use of tiny, low cost capacitors and inductors. DC233 contains three switching regulator circuits. Two of these demonstrate the use of the LT1613CS5 in a simple boost regulator circuit and in an uncoupled SEPIC circuit. Both circuits produce 3.3V or 5V (jumper selected). The boost circuit produces 200mA in a typical application and occupies less than 0.2 square inches of circuit board area. The SEPIC circuit allows operation from input voltages either higher or lower than the output, making this circuit suitable for single Li-Ion cell to 3.3V conversion or four alkaline cells to 5V conversion. Typical output current for the SEPIC circuit is 120mA. The third circuit demonstrates the LT1611CS5 in a low noise inverting circuit. This circuit can convert 5V to –5V at 160mA.
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:
LT Journal (4)
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.