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LM3478Q-Q1

ACTIVE

40-V wide VIN low-side N-channel controller for switching regulators with 10-µA shutdown current

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LM5155-Q1 ACTIVE 2.2-MHz wide VIN, 1.5-A MOSFET driver, non-synchronous boost controller, AEC-Q100 qualified Up to 2.2-MHz Fsw, higher efficiency and up to 45-V input operating voltage.

LM3478Q-Q1

ACTIVE
Data sheet Order now

Product details

Vin (min) (V) 2.97 Vin (max) (V) 40 Operating temperature range (°C) -40 to 125 Control mode current mode Topology Boost, Flyback, Forward, SEPIC Rating Automotive Vout (min) (V) 1.26 Vout (max) (V) 500 Features Adjustable current limit, Enable, Frequency synchronization, Light Load Efficiency, Nonsynchronous rectification, Pre-Bias Start-Up Iq (typ) (µA) 2700 Duty cycle (max) (%) 100
Vin (min) (V) 2.97 Vin (max) (V) 40 Operating temperature range (°C) -40 to 125 Control mode current mode Topology Boost, Flyback, Forward, SEPIC Rating Automotive Vout (min) (V) 1.26 Vout (max) (V) 500 Features Adjustable current limit, Enable, Frequency synchronization, Light Load Efficiency, Nonsynchronous rectification, Pre-Bias Start-Up Iq (typ) (µA) 2700 Duty cycle (max) (%) 100
VSSOP (DGK) 8 14.7 mm² 3 x 4.9
  • LM3478Q-Q1 is AEC-Q100 Qualified and Manufactured on an Automotive Grade Flow
  • 8-lead VSSOP-8
  • Internal Push-Pull Driver With 1-A Peak Current Capability
  • Current Limit and Thermal Shutdown
  • Frequency Compensation Optimized With a Capacitor and a Resistor
  • Internal Soft Start
  • Current Mode Operation
  • Undervoltage Lockout With Hysteresis
  • Create a Custom Design Using the LM3478 with the WEBENCH Power Designer
  • LM3478Q-Q1 is AEC-Q100 Qualified and Manufactured on an Automotive Grade Flow
  • 8-lead VSSOP-8
  • Internal Push-Pull Driver With 1-A Peak Current Capability
  • Current Limit and Thermal Shutdown
  • Frequency Compensation Optimized With a Capacitor and a Resistor
  • Internal Soft Start
  • Current Mode Operation
  • Undervoltage Lockout With Hysteresis
  • Create a Custom Design Using the LM3478 with the WEBENCH Power Designer

The LM3478Q-Q1 is a versatile Low-Side N-Channel MOSFET controller for switching regulators. It is suitable for use in topologies requiring a low side MOSFET, such as boost, flyback, SEPIC, etc. Moreover, the LM3478Q-Q1 can be operated at extremely high switching frequency in order to reduce the overall solution size. The switching frequency of the LM3478Q-Q1 can be adjusted to any value between 100 kHz and 1 MHz by using a single external resistor. Current mode control provides superior bandwidth and transient response, besides cycle-by-cycle current limiting. Output current can be programmed with a single external resistor.

The LM3478Q-Q1 has built in features such as thermal shutdown, short-circuit protection, over voltage protection, etc. Power saving shutdown mode reduces the total supply current to 5 µA and allows power supply sequencing. Internal soft-start limits the inrush current at start-up.

The LM3478Q-Q1 is a versatile Low-Side N-Channel MOSFET controller for switching regulators. It is suitable for use in topologies requiring a low side MOSFET, such as boost, flyback, SEPIC, etc. Moreover, the LM3478Q-Q1 can be operated at extremely high switching frequency in order to reduce the overall solution size. The switching frequency of the LM3478Q-Q1 can be adjusted to any value between 100 kHz and 1 MHz by using a single external resistor. Current mode control provides superior bandwidth and transient response, besides cycle-by-cycle current limiting. Output current can be programmed with a single external resistor.

The LM3478Q-Q1 has built in features such as thermal shutdown, short-circuit protection, over voltage protection, etc. Power saving shutdown mode reduces the total supply current to 5 µA and allows power supply sequencing. Internal soft-start limits the inrush current at start-up.
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* Data sheet LM3478Q-Q1 High-Efficiency Low-Side N-Channel Controller for Switching Regulator datasheet PDF | HTML 16 Jun 2017

Design & development

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Calculation tool

FLYBUCK-FLYBACK-DESIGN-CALC — Flybuck / Flyback Calculator

This tool helps a power supply engineer to select the right isolated DC-DC topology based on the specifications. Depending on the topology chosen, the calculator also recommends the right IC for the design.

Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC controllers (external FET)
LM3017 — High Efficiency Low-Side Controller with True Shutdown LM3478 — 2.97~40V Wide Input Range Boost/SEPIC/Flyback DC-DC Controller LM3478Q-Q1 — 40-V wide VIN low-side N-channel controller for switching regulators with 10-µA shutdown current LM3481 — 2.97V to 48V High-Efficiency Controller for Boost, SEPIC and Flyback LM3481-Q1 — 2.97-V to 48-V high-efficiency controller for boost, SEPIC and flyback, AEC-Q100 qualified LM3488 — 2.97V to 40V Wide Vin Low-Side N-Channel Controller for Switching Regulators LM3488Q-Q1 — 40-V wide VIN low-side N-channel controller for switching regulators with 5-µA shutdown current LM3524D — 40V, 0.2A 350KHz PWM controller LM3578A — 2-V to 40-VIN switching regulators in buck, boost, terminal, depending upon the application LM5020 — 13-100V Wide Vin, Current Mode PWM Boost, Flyback, Sepic Controller LM5022 — 6-60V Wide Vin, current mode boost, SEPIC and Flyback controller TL1451 — Dual Pulse-Width-Modulation Control Circuit TL1451A — 3.6V to 50V dual channel controller with Wide input voltage range TL1451A-EP — Enhanced Product Dual Pulse-Width-Modulation Control Circuits TL1451A-Q1 — 3.6-V to 50-V dual-channel PWM controller, AEC-Q100 qualified TL5001 — PWM Controller with wide input range, with ±5% tolerance on reference, operation –20°C to 85°C TL5001A — PWM Controller with wide input range, with ±3% tolerance on reference, operation –20°C to 85°C TL5001A-Q1 — PWM Controller with wide input range, with ±3% tolerance on reference, operation –20°C to 85°C TL5001M — PWM Controller with wide input range, with ±5% tolerance on reference, operation –55°C to 125°C TPS40210-Q1 — 4.5-V to 52-V wide input range current mode boost controller with 700-mV reference voltage TPS40211-Q1 — 4.5-V to 52-V wide input range current mode boost controller with 260-mV reference voltage TPS43000 — Multi-Topology (buck, boost, sepic) High Frequency DC/DC Controller TPS55010 — 2.95V To 6V Input, 2W, Isolated DC/DC Converter with Integrated FETS UC2572 — Negative output Flyback pulse width modulator
AC/DC & DC/DC converters (integrated FET)
LM25017 — 7.5-48V Wide Vin, 650mA Constant On-Time Synchronous Buck Regulator LM25018 — 7.5-48V Wide Vin, 300mA Constant On-Time Synchronous Buck Regulator LM25019 — 7.5-48V Wide Vin, 100mA Constant On-Time Synchronous Buck Regulator LM2577 — 3.5-V to 40-V, 3-A low component count step-up regulator LM2585 — 4-V to 40-V, 3-A step-up wide VIN flyback regulator LM2586 — 4-V to 40-V, 3-A step-up wide VIN flyback regulator with frequency synchronization LM2587 — 4V to 40V, 5A Step-Up Wide Vin Flyback Regulator LM2588 — 4-V to 40-V, 5-A step-up wide VIN flyback regulator with frequency synchronization LM2621 — 1.2V to 14V input voltage, 1A load current, step-up DC-DC LM2623 — 0.8V to 14V input voltage, 2A load current, step-up DC-DC LM2623-Q1 — 0.8-V to 14-V input voltage, 2-A load current, step-up DC/DC, AEC-Q100 qualified LM2735 — 520kHz/1.6MHz space efficient boost and SEPIC DC-DC regulator LM2735-Q1 — 520-kHz, 1.6-MHz space efficient boost and SEPIC DC/DC regulator, AEC-Q100 qualified LM34925 — 7.5-100V Wide Vin, 100mA Integrated Secondary Bias Regulator for Isolated DC/DC Converters LM34926 — 7.5-100V Wide Vin, 300mA Integrated Secondary Bias Regulator for Isolated DC/DC Converters LM34927 — 7.5-100V Wide Vin, 600mA Integrated Secondary Bias Regulator for Isolated DC/DC Converters LM5000 — 3.1-40V Wide Vin, 2A Current Mode Non-Synchronous Boost Regulator LM5001 — 3.1-75V Wide Vin, 1A Current Mode Non-Synchronous Switch Mode Regulator LM5001-Q1 — 3.1-V to 75-V wide VIN, 1-A current mode non-synchronous switch mode regulator LM5002 — 3.1-75V Wide Vin, 0.5A Current Mode Boost, Flyback, Sepic Converter LM5015 — 4.25-75V, Monolithic Two-Switch Forward DC-DC Regulator LM5017 — 7.5-100V Wide Vin, 600mA Constant On-Time Synchronous Buck Regulator LM5018 — 7.5-100V Wide Vin, 300mA Constant On-Time Synchronous Buck Regulator LM5019 — 7.5-100V Wide Vin, 100mA Constant On-Time Synchronous Buck Regulator LM5160 — LM5160 wide input 65V, 2A synchronous buck/Fly-Buck™ converter LM5160-Q1 — Wide Input 65V, 2A Synchronous Buck / Fly-Buck™ Converter LM5160A — LM5160A Wide Input 65V, 2A Synchronous Buck / Fly-Buck™ Converter LM5161 — Wide Input 4.5-V to 100-V, 1-A Synchronous Buck / Fly-Buck Converter LM78S40 — 1.5A Adjustable Step Up, Step Down or Inverting Regulator TPS55340 — 5-A, 40-V, wide VIN boost, flyback, & SEPIC converter TPS55340-EP — Enhanced integrated, 5-A, 40-V wide input range boost/SEPIC/flyback DC/DC regulator TPS55340-Q1 — Integrated, 5-A 40-V wide input range boost/SEPIC/flyback DC/DC regulator, AEC-Q100 qualified TPS61175 — 3-A ,40V High Voltage Boost Converter with Soft-start and Programmable Switching Frequency TPS61175-Q1 — 3-A, 40-V high voltage boost converter with soft-start and programmable switching frequency
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Calculation tool

LM3478-88-BOOST-CALC — LM3478-88 quick start calculator for boost

LM3478-88 quick start calculator for boost topology
Supported products & hardware

Supported products & hardware

Products
AC/DC & DC/DC controllers (external FET)
LM3478 — 2.97~40V Wide Input Range Boost/SEPIC/Flyback DC-DC Controller LM3478Q-Q1 — 40-V wide VIN low-side N-channel controller for switching regulators with 10-µA shutdown current LM3488 — 2.97V to 40V Wide Vin Low-Side N-Channel Controller for Switching Regulators LM3488Q-Q1 — 40-V wide VIN low-side N-channel controller for switching regulators with 5-µA shutdown current
Hardware development
Evaluation board
LM3478EVAL — High Efficiency Low-Side N-Channel Controller for Switching Regulator
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Reference designs

PMP9382 — High-Efficiency Low Vin 30W Boost Converter for Automotive Applications (E-Call) Reference Design

PMP9382 is a low Vin boost converter utilizing the automotive grade LM3478Q-Q1 controller. This design starts at a diode drop above the minimum input voltage of 2.97V (~3.4V) to a maximum of 6V in.  Once the power supply is enabled and output is present, this design will work down to 2V input (...)
Test report: PDF
Schematic: PDF
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VSSOP (DGK) 8 Ultra Librarian
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