Overview
Features and Benefits
- Wide Input Voltage Range: 4V to 30V
- Wide Output Voltage Range: 0.8V to VIN
- Low Shutdown IQ: 20μA
- Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise
- 0.8V ±1.5% Voltage Reference
- 500kHz Current Mode Fixed Frequency Operation
- Internal Boost Converter Provides Bias Rail for N-Channel MOSFET Gate Drive
- Power Good Voltage Monitor for Each Output
- Programmable Soft-Start
- 24-Lead 4mm × 4mm × 0.75mm Package
Product Details
The LT3742 is a dual step-down DC/DC switching regulator controller that drives high side N-channel power MOSFETs. A 500kHz fixed frequency current mode architecture provides fast transient response with simple loop compensation components and cycle-by-cycle current limiting. The output stages of the two controllers operate 180° out of phase to reduce the input ripple current, minimizing the noise induced on the input supply, and allowing less input capacitance.
An internal boost regulator generates a bias rail of VIN + 7V to provide gate drive for the N-channel MOSFETs allowing low dropout and 100% duty cycle operation. The LT3742 can be used for applications where both controllers need to operate independently, or where both controllers are used to provide a single higher current output.
The device is available in a thermally enhanced 4mm × 4mm QFN package.
Applications
- Satellite and Cable TV Set-Top Boxes
- Distributed Power Regulation
- Automotive Systems
- Super Capacitor Charger
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)
Documentation
Reliability Data (1)
User Guides (1)
Tools & Simulations
LTspice
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.
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Models for the following parts are available in LTspice:
Reference Materials
Technical Articles (1)
Design Resources
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PCN-PDN Information
Support & Discussions
LT3742 Discussions
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.
Sampling:
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Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.