LT1931
PRODUCTION1.2MHz/2.2MHz Inverting DC/DC Converters in ThinSOT
- Part Models
- 8
- 1ku List Price
- Starting From $2.94
Overview
- Fixed Frequency 1.2MHz/2.2MHz Operation
- Very Low Noise: 1mVP-P Output Ripple
- –5V at 350mA from 5V Input
- –12V at 150mA from 5V Input
- Uses Small Surface Mount Components
- Wide Input Range: 2.6V to 16V
- Low Shutdown Current: <1µA
- Low VCESAT Switch: 400mV at 1A
- Pin-for-Pin Compatible with the LT1611
- Low Profile (1mm) ThinSOT™ Package
The LT1931/LT1931A are the industry’s highest power inverting SOT-23 current mode DC/DC converters. Both parts include a 1A integrated switch allowing high current outputs to be generated in a small footprint. The LT1931 switches at 1.2MHz while the LT1931A switches at 2.2MHz. These high speeds enable the use of tiny, low cost capacitors and inductors 2mm or less in height. The LT1931 is capable of generating –5V at 350mA or –12V at 150mA from a 5V supply, while the LT1931A can generate –5V at 300mA using significantly smaller inductors. Both parts are easy pin-for-pin upgrades for higher power LT1611 applications.
The LT1931/LT1931A operate in a dual inductor inverting topology that filters both the input side and output side current. Very low output voltage ripple approaching 1mVP-P can be achieved when ceramic output capacitors are used. Fixed frequency switching ensures a clean output free from low frequency noise typically present with charge pump solutions. The low impedance output remains within 1% of nominal during large load steps. The 36V switch allows VIN to VOUT differential of up to 34V.
The LT1931/LT1931A are available in the 5-lead ThinSOT package.
Applications
- Disk Drive MR Head Bias
- Digital Camera CCD Bias
- LCD Bias
- GaAs FET Bias
- Local Low Noise/Low Impedance Negative Supply
Documentation
Data Sheet 1
User Guide 2
Technical Articles 1
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 Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| LT1931AES5#TRMPBF | 5-Lead TSOT-23 | ||
| LT1931AES5#TRPBF | 5-Lead TSOT-23 | ||
| LT1931AIS5#TRMPBF | 5-Lead TSOT-23 | ||
| LT1931AIS5#TRPBF | 5-Lead TSOT-23 | ||
| LT1931ES5#TRMPBF | 5-Lead TSOT-23 | ||
| LT1931ES5#TRPBF | 5-Lead TSOT-23 | ||
| LT1931IS5#TRMPBF | 5-Lead TSOT-23 | ||
| LT1931IS5#TRPBF | 5-Lead TSOT-23 |
This is the most up-to-date revision of the Data Sheet.
Software Resources
Can't find the software or driver you need?
Request a Driver/SoftwareHardware Ecosystem
| Parts | Product Life Cycle | Description |
|---|---|---|
| Overvoltage & Overcurrent Protectors 1 | ||
| LTC4365 | RECOMMENDED FOR NEW DESIGNS | Overvoltage, Undervoltage and Reverse Supply Protection Controller |
Tools & Simulations
LTspice 2
- LT1931A Demo Circuit - 1.2MHz/2.2MHz Inverting DC/DC Converters (5V to -5V @ 350mA)
- LT1931A Demo Circuit - 1.2MHz/2.2MHz Inverting DC/DC Converters (5V to -5V @ 300mA)
Models for the following parts are available in LTspice:
- LT1931
- LT1931A
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.
Evaluation Kits
LTC1930ES5/LTC1931ES5 Demo Board | 3 Circuits: Boost/SEPIC/Inverter, 5VIN to 12VOUT1 @300mA, 10V-16VIN to 12VOUT2 @300mA, 12VIN to -12VOUT3 @350mA
Resources
LT1930AES5/LT1931AES5 Demo Board | 3 Circuits: Boost/SEPIC/Inverter: 5VIN to 12VOUT1 @ 250mA, 10V-16VIN to 12VOUT2 @ 250mA, 12VIN to -12VOUT3 @ 250mA
Resources
Reference Designs
Analog Front End and Digital Interface for Serial LVDS SAR ADCs
Part Used
Design & Integration Tools
Part Used
Part Used
