150V Low IQ, Synchronous Step-Down DC/DC Controller
Features and Benefits
- Wide VIN + |VOUT–| Range: 4V to 140V (150V Abs Max)
- Wide Output Voltage Range: –60V to –0.8V
- Ground-Referenced Control / Interface Pins
- Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)
- Integrated Bootstrap Diode
- Low Operating IQ: 40μA (Shutdown = 10μA)
- Selectable Gate Drive UVLO Thresholds
- Onboard LDO or External NMOS LDO for DRVCC
- EXTVCC LDO Powers Drivers from Output
- Phase-Lockable Frequency (75kHz to 850kHz)
- Programmable Fixed Frequency (50kHz to 900kHz)
- Selectable Continuous, Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads
- Adjustable Burst Clamp and Current Limit
- Power Good Output Voltage Monitor
- Programmable Input Overvoltage Lockout
- 38-Lead TSSOP High Voltage Package
The LTC3896 is a high performance inverting DC/DC switching regulator controller that drives an all N-channel synchronous power MOSFET stage. It converts a wideranging positive input voltage source to a regulated negative output that can be as much as 60V below ground. The input can operate from a voltage as low as 4V and as high as 140V – |VOUT–|.
The LTC3896 contains true ground-referenced RUN, PLLIN and PGOOD pins, eliminating the need for external discrete level-shifting components to interface with the LTC3896.
A constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. The low 40μA no-load quiescent current extends operating run time in battery-powered systems. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3896 features a precision 0.8V reference and power good output indicator. The soft-start (SS) pin ramps the output voltage during start-up.
- Automotive and Industrial Power Systems
- Telecommunications 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 2447A is a high voltage, high efficiency synchronous inverting converter featuring the LTC3896. This demo board has a wide input voltage range from 7V to 72V and produces a –12V output voltage.
The DC2447A is capable of delivering up to 5A of output current. Note that the thermal stress increases at lower input voltages due to increased input current.
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.
Models for the following parts are available in LTspice:
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
To open the project file for this circuit:
Step 1: Download and install LTpowerCAD on your computer.
Step 2: Click on the link(s) in the section below to download part-specific project files.
Step 3: If the project file doesn't run, right-click the link and select "Save Target As." Then start the LTpowerCAD tool and open the project file by selecing "Open Project" from the "File" menu.
LTpowerCAD Project Files
Design tools for the following parts are available in LTpowerCAD:
LTC3896 Companion Parts
Recommended Related Parts
Design Notes (1)
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.
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.