7.0 V to 26.0 V Input, 1 A Integrated MOSFET Single Synchronous Buck DC/DC Converter - BD9E104FJ

BD9E104FJ is a synchronous buck DC/DC converter with built-in low on-resistance power MOSFETs. High efficiency at light load with a SLLMTM (Simple Light Load Mode). It is most suitable for use in the equipment to reduce the standby power is required. It is a current mode control DC/DC converter and features high-speed transient response. Phase compensation can also be set easily.

* This is a standard-grade product.
For Automotive usage, please contact Sales.

Technical Documents

Application Note

Method for Monitoring Switching Waveform
This application note explains how to correctly monitor the switching waveforms of the power device element such as switching power supply or a motor drive circuit.
PCB Layout for BD9E104FJ
When designing switching nodes that operate at high speeds and switching power supplies that use a large current, PCB layout design is as important as circuit design...
Suppression Method of Switching Noise Using Linear Regulator and Low Pass Filter
This application note describes the method and result of the ripple and switching noise suppression using a linear regulator and a low pass filter.
Phase Compensation Design for Current Mode Buck Converter
This application note explains the method used by ROHM for designing the phase compensation for current mode buck converters.
PCB Layout Techniques of Buck Converter
Major problems that arise from in appropriate layout may cause increase in noise superposed by output and switching signal, the deterioration of regulator, and also lack of stability...
Bootstrap Circuit in the Buck Converter
This application note explains the step-up circuit using a bootstrap capacitor. In buck converters, this circuit is used when the highside switch is the N-ch MOSFET.
Power Supply Sequence Circuit with General Purpose Power Supply IC
This application note proposes a circuit that accomplishes the power supply sequence without using any dedicated power supply sequence IC, by using general purpose power supply ICs.
Method for Determining Constants of
This application note explains the procedures for determining the constants of peripheral parts of a buck DC/DC converter.
Measurement Method for Phase Margin with Frequency Response Analyzer (FRA)
This application note introduces a method for easily measuring the phase margin with a Frequency Response Analyzer (FRA) made by NF Corporation.
Usage of SPICE Macromodel for DC/DC
This application note explains how to install SPICE macromodels and how the circuit symbols are configured.
Snubber Circuit for Buck Converter IC
In buck converter ICs, many high-frequency noises are generated at switch nodes. A snubber circuit provides one way of eliminating such harmonic noise. This application note explains how to set up the RC snubber circuits.
Efficiency of Buck Converter
This application note explains power loss factors and methods for calculating them. It also explains how the relative importance of power loss factors depends on the specifications of the switching power source.
Calculation of Power Loss (Synchronous)
This application note describes how to obtain the power loss required to calculate the temperature of a semiconductor device. Temperature control is important to ensuring product reliability.
Thermal Resistance
The definition and how to use thermal resistance and thermal characterization parameter of packages for ROHM’s integrated circuit are described in this application note.
Inductor Calculation for Buck converter IC
This application note covers the steps required in choosing the inductor and to calculate the value used in buck regulator IC circuits.
Considerations for Power Inductors Used for Buck Converters
This application note explains the features and things to consider when shopping for power inductors.
Capacitor Calculation for Buck converter IC
This application note explains the calculation of external capacitor value for buck converter IC circuit.
The Important Points of Multi-layer Ceramic Capacitor Used in Buck Converter circuit
Using unmatched MLCC may not obtain required target characteristics for power supply circuit and may cause abnormal operation. This application note explains the important points while using MLCC.
Resistor Value Table to set Output Voltage of Buck Converter IC
This Application Note offers reference table to easily set resistor values for output voltage with various internal reference voltages VREF.
Part Explanation
For ICs

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Environmental Data

REACH SVHC Non-use Declaration


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