Features and Benefits
- Automatic Step-Up and Step-Down Conversion
- Uses a Single Inductor
- Wide 4V to 60V Input Voltage Range
- VOUT from 3.3V to 20V
- Dual Internal 500mA Switches
- 100µA No-Load Quiescent Current
- Low Current Shutdown
- ±1% Output Voltage Accuracy
- 200kHz Operating Frequency
- Boosted Supply Pin to Saturate High Side Switch
- Frequency Foldback Protection
- Current Limit Foldback Protection
- Current Limit Unaffected by Duty Cycle
- 16-lead Thermally Enhanced TSSOP Package
The LT3433 is a 200kHz fixed-frequency current mode switching regulator that provides both step-up and stepdown regulation using a single inductor. The IC operates over a 4V to 60V input voltage range making it suitable for use in various wide input voltage range applications such as automotive electronics that must withstand both load dump and cold crank conditions.
Internal control circuitry monitors system conditions and converts from single switch buck operation to dual switch bridged operation when required, seamlessly changing between step-down and step-up voltage conversion.
Optional Burst Mode® operation reduces no-load quiescent current to 100µA and maintains high efficiencies with light loads.
Current limit foldback and frequency foldback help prevent inductor current runaway during start-up. Programmable soft-start helps prevent output overshoot at start-up.
The LT3433 is available in a 16-lead thermally enhanced TSSOP package.
- 12V Automotive Systems
- Wall Adapter Powered Systems
- Battery Power Voltage Buffering
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 527 is a monolithic step-up/step-down DC/DC switching converter with Burst Mode™ featuring the LT3433. The board is optimized for 5V output at up to 400mA load current (12VIN) and an input voltage range of 4V to 60V. The demo board is also useful for buck-only needs and can provide 5V @ 340mA from a 48V input and 5V @ 400mA from a 12V input.
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.
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Step 2: Click on the link in the section below to download a demonstration circuit.
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Models for the following parts are available in LTspice:
Reference Designs (1)
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Sample & Buy
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