Features and Benefits
- Wide Operating VIN Range: 3.5V to 60V
- Wide Negative VOUT Range: –0.4V to Beyond –150V
- Low Operating IQ = 70μA
- Strong High Voltage MOSFET Gate Driver
- Constant Frequency Current Mode Architecture
- Verified FMEA for Adjacent Pin Open/Short
- Selectable High Efficiency Burst Mode® Operation or Pulse-Skipping Mode at Light Loads
- Programmable Fixed Frequency: 50kHz to 850kHz
- Phase-Lockable Frequency: 75kHz to 750kHz
- Accurate Current Limit
- Programmable Soft-Start or Voltage Tracking
- Internal Soft-Start Guarantees Smooth Start-Up
- Low Shutdown IQ = 7μA
- Available in Small 12-Lead Thermally Enhanced MSOP and DFN Packages
The LTC3863 is a robust, inverting DC/DC PMOS controller optimized for automotive and industrial applications. It drives a P-channel power MOSFET to generate a negative output and requires just a single inductor to complete the circuit. Output voltages from –0.4V to –150V are typically achievable with higher voltages possible, only limited by external components.
The LTC3863 offers excellent light load efficiency, drawing only 70μA quiescent current in a user programmable Burst Mode operation. Its peak current mode, constant frequency PWM architecture provides for good control of switching frequency and output current limit. The switching frequency can be programmed from 50kHz to 850kHz with an external resistor and can be synchronized to an external clock from 75kHz to 750kHz.
The LTC3863 offers programmable soft-start or output tracking. Safety features include overvoltage, overcurrent and short-circuit protection including frequency foldback.
The LTC3863 is available in thermally enhanced 12-lead MSOP and 3mm × 4mm DFN packages.
- Industrial and Automotive Power Supplies
- Telecom Power Supplies
- Distributed Power Systems
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 1737A is a current-mode inverting DC/DC converter featuring the LTC3863. The board operates from an input range of 4.5V to 16V, and provides a –5.2V, 1.7A output or a –12V, 1A output (jumper selectable). It operates at 400kHz and may be synchronized to an external clock. A soft-start feature controls output voltage slew rate at start-up, reducing current surge and voltage overshoot. Burst Mode® operation that improves efficiency at light loads can be enabled with a jumper. A power good output signal is provided. The demonstration board has options for larger MOSFET and diode packages on the back of the board for higher output current requirements.
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:
LTC3863 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.