L4973

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3.5 A step down switching regulator

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Overview

Product overview

Description

Description

The L4973 is a step down monolithic power switching regulator delivering 3.5A at fixed voltages of 3.3V or 5.1V and using a simple external divider output adjustable voltage up to 50V. Realized in BCD mixed technology, the device uses an internal power D-MOS transistor (with a typical RDS(on) of 0.15Ω) to obtain very high efficiency and very fast switching times. Switching frequency up to 300KHz are achievable (the maximum power dissipation of the packages must be observed).

A wide input voltage range between 8V to 55V and output voltages regulated from 3.3V to 40V cover the majority of the today applications. Features of this new generation of DC-DC converter includes pulse by pulse current limit, hiccup mode for output short circuit protection, voltage feed forward regulation, soft start, input/output synchronization, protection against feedback loop disconnection, inhibit for zero current consumption and thermal shutdown. Packages available are in plastic dual in line, DIP- 18 (12+3+3) for standard assembly, and SO20 (12+4+4) for SMD assembly.

  • All features

    • Inhibit for zero current consumption (100mA at VCC= 24V)
    • Input/output synchronization function
    • Thermal shutdown
    • Protection against feedback disconnection
    • Soft start function
    • Output over voltage protection
    • Internal current limiting (pulse by pulse and HICCUP mode)
    • Zero load current operation (min 1mA)
    • Up to 3.5A step down converter
    • 3.3V and 5.1V (±1%) fixed output, and adjustable outputs from: 0.5V to 50V (3.3 type)5.1V to 50V (5.1 type)
    • Operating input voltage from 8V to 55V
    • Voltage feed forward
    • Precise 5.1V (1.5%) reference voltage externally available
    • Frequency adjustable up to 300kHz

Circuit Diagram

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The current status of a product:
Active: Product is in volume production
Evaluation: Product is under characterization. Limited Engineering samples available
Preview: Product is in design stage
Target: Product is in design feasibility stage.No commitment taken to produce
Proposal: Marketing proposal for customer feedback.No commitment taken to design or produce
NRND: Not Recommended for New Design.Product is in volume production only to support customers ongoing production.Marketing description of the package type.Compliancy of the device with industry requirement domains (IRD)The RoHS status of a product:
ECOPACK 1: Initial grade to identify European RoHS compliant products.
ECOPACK 2: New grade to identify brominated chlorinated and antimony oxide flame retardant free products.
ECOPACK 3: Halogen free RoHS exemptions free products.
(*): ECOPACK 2 version available upon request.
(**): Some versions still existing in ECOPACK 1 or not compliant.The current status of a product:
Active: Product is in volume production
Evaluation: Product is under characterization. Limited Engineering samples available
Preview: Product is in design stage
Target: Product is in design feasibility stage.No commitment taken to produce
Proposal: Marketing proposal for customer feedback.No commitment taken to design or produce
NRND: Not Recommended for New Design.Product is in volume production only to support customers ongoing production.Budgetary PriceMarketing description of the package type.Storage method used to contain product.Main country of assembly or fabrication of the product.ECCNs are five character alpha-numeric designations used on the Commerce Control List to identify dual-use items for export control purposes. ECCNs are five character alpha-numeric designations used on the Commerce Control List to identify dual-use items for export control purposes.The value as specified by level (minTypMax) of the ambient temperature (in Cel) in which this item was designed to operate.The value as specified by level (minTypMax) of the ambient temperature (in Cel) in which this item was designed to operate.