Passive Components Blog
No Result
View All Result
  • Home
  • NewsFilter
    • All
    • Aerospace & Defence
    • Antenna
    • Applications
    • Automotive
    • Capacitors
    • Circuit Protection Devices
    • electro-mechanical news
    • Filters
    • Fuses
    • Inductors
    • Industrial
    • Integrated Passives
    • inter-connect news
    • Market & Supply Chain
    • Market Insights
    • Medical
    • Modelling and Simulation
    • New Materials & Supply
    • New Technologies
    • Non-linear Passives
    • Oscillators
    • Passive Sensors News
    • Resistors
    • RF & Microwave
    • Telecommunication
    • Weekly Digest

    Rubycon Extends Capacitance of Polymer Hybrid Aluminum Capacitors

    VINATech Partner with ONiO to Develop Batteryless IoT Power Architecture

    Knowles Releases Inductors for Mission-Critical RF Applications

    Bourns Unveils Smallest Automotive Grade Thick Film Resistors

    Wk 28 Electronics Supply Chain Digest

    Bourns Increases Maximum Inductance Values of Semi-Shielded Power Inductors

    YAGEO Unveils Next Gen BMS Isolation Transformers

    Littelfuse Compact Tactile Switch Offers Low-Noise Switching and Dust Protection

    Murata Announces Mass Manufacturing of World’s First 0402 47µF MLCC

    Trending Tags

    • Ripple Current
    • RF
    • Leakage Current
    • Tantalum vs Ceramic
    • Snubber
    • Low ESR
    • Feedthrough
    • Derating
    • Dielectric Constant
    • New Products
    • Market Reports
  • VideoFilter
    • All
    • Antenna videos
    • Capacitor videos
    • Circuit Protection Video
    • Filter videos
    • Fuse videos
    • Inductor videos
    • Inter-Connect Video
    • Non-linear passives videos
    • Oscillator videos
    • Passive sensors videos
    • Resistor videos

    Accelerating Full Bridge LLC Resonant Converter Design with Frenetic AI

    Understanding Switched Capacitor Converters

    Coupled Inductors Circuit Model and Examples of its Applications

    Inductor Resonances and its Impact to EMI

    Highly Reliable Flex Rigid PCBs, Würth Elektronik Webinar

    Causes of Oscillations in Flyback Converters

    How to design a 60W Flyback Transformer

    Modeling and Simulation of Leakage Inductance

    Power Inductor Considerations for AI High Power Computing – Vishay Video

    Trending Tags

    • Capacitors explained
    • Inductors explained
    • Resistors explained
    • Filters explained
    • Application Video Guidelines
    • EMC
    • New Products
    • Ripple Current
    • Simulation
    • Tantalum vs Ceramic
  • Knowledge Blog
  • Suppliers
    • Who is Who
  • Events
  • Home
  • NewsFilter
    • All
    • Aerospace & Defence
    • Antenna
    • Applications
    • Automotive
    • Capacitors
    • Circuit Protection Devices
    • electro-mechanical news
    • Filters
    • Fuses
    • Inductors
    • Industrial
    • Integrated Passives
    • inter-connect news
    • Market & Supply Chain
    • Market Insights
    • Medical
    • Modelling and Simulation
    • New Materials & Supply
    • New Technologies
    • Non-linear Passives
    • Oscillators
    • Passive Sensors News
    • Resistors
    • RF & Microwave
    • Telecommunication
    • Weekly Digest

    Rubycon Extends Capacitance of Polymer Hybrid Aluminum Capacitors

    VINATech Partner with ONiO to Develop Batteryless IoT Power Architecture

    Knowles Releases Inductors for Mission-Critical RF Applications

    Bourns Unveils Smallest Automotive Grade Thick Film Resistors

    Wk 28 Electronics Supply Chain Digest

    Bourns Increases Maximum Inductance Values of Semi-Shielded Power Inductors

    YAGEO Unveils Next Gen BMS Isolation Transformers

    Littelfuse Compact Tactile Switch Offers Low-Noise Switching and Dust Protection

    Murata Announces Mass Manufacturing of World’s First 0402 47µF MLCC

    Trending Tags

    • Ripple Current
    • RF
    • Leakage Current
    • Tantalum vs Ceramic
    • Snubber
    • Low ESR
    • Feedthrough
    • Derating
    • Dielectric Constant
    • New Products
    • Market Reports
  • VideoFilter
    • All
    • Antenna videos
    • Capacitor videos
    • Circuit Protection Video
    • Filter videos
    • Fuse videos
    • Inductor videos
    • Inter-Connect Video
    • Non-linear passives videos
    • Oscillator videos
    • Passive sensors videos
    • Resistor videos

    Accelerating Full Bridge LLC Resonant Converter Design with Frenetic AI

    Understanding Switched Capacitor Converters

    Coupled Inductors Circuit Model and Examples of its Applications

    Inductor Resonances and its Impact to EMI

    Highly Reliable Flex Rigid PCBs, Würth Elektronik Webinar

    Causes of Oscillations in Flyback Converters

    How to design a 60W Flyback Transformer

    Modeling and Simulation of Leakage Inductance

    Power Inductor Considerations for AI High Power Computing – Vishay Video

    Trending Tags

    • Capacitors explained
    • Inductors explained
    • Resistors explained
    • Filters explained
    • Application Video Guidelines
    • EMC
    • New Products
    • Ripple Current
    • Simulation
    • Tantalum vs Ceramic
  • Knowledge Blog
  • Suppliers
    • Who is Who
  • Events
No Result
View All Result
Passive Components Blog
No Result
View All Result

TI Buck Regulators with Integrated Capacitors Suppress EMI and Save Board Space

24.8.2022
Reading Time: 4 mins read
A A

Texas Instruments (TI) releases buck regulators with integrated capacitors to suppress EMI and save board space.

TI rolled out a new pair of synchronous step-down dc-dc converters—the industrial-grade LMQ66430 and automotive-grade LMQ66430-Q1—designed to reduce EMI on factory floors and in medical devices, autos, aerospace, and defense. The 36-V, 3-A buck converters combine two input bypass capacitors with a single boot capacitor in a compact 2.6- × 2.6-mm QFN package with wettable flanks, helping boost power density.

RelatedPosts

Rubycon Extends Capacitance of Polymer Hybrid Aluminum Capacitors

VINATech Partner with ONiO to Develop Batteryless IoT Power Architecture

Knowles Releases Inductors for Mission-Critical RF Applications

“We’re combining IP and in-package innovations. In today’s electric vehicles, you have so many more systems, and these systems are all very sensitive,” he said, including the high-voltage electronics and various power converters, all placed close together in the vehicle. There are also thousands of feet of cabling in electric vehicles, which can lead to large amounts of EMI. “We have to protect these systems from interfering with each other and it’s really complex,” said Carsten Oppitz, VP and GM of buck switching regulators at TI

The Buck Converter Design Challenge

It’s a challenge to create highly efficient and compact designs while also adhering to strict electromagnetic interference (EMI) requirements imposed by groups such as Comité International Spécial des Perturbations Radioélectriques (CISPR). Therefore, component selection becomes a critical part of the design process.

As with most design decisions, choosing between different components almost always comes down to an assessment of tradeoffs based on your most critical design goals. Known for high efficiency and good thermal performance, buck regulators are not typically considered low-EMI options. Fortunately, you have several options for reducing the EMI generated by such regulators. To aid further discussion, Figure 1 shows a simplified buck regulator schematic.

Figure 1: Simplified buck regulator schematic

Board layout considerations

Beyond selecting proper passive component values to ensure a functional design, board layout should be your first consideration when your design must fall under EMI limits. There are two general rules that can help minimize generated EMI with all buck regulator board layouts:

  • Minimize high transient current (di/dt) loop areas by bringing the input capacitor and boot capacitor as close to the VIN and GND pins of the integrated circuit as possible.
  • Minimize the surface area of high transient voltage (dv/dt) nodes by minimizing the area of the switch node.

Integrated input capacitors

As I mentioned, reducing the area of high di/dt current loops is very important when designing switching regulators to remain under EMI limits. In a buck regulator, it’s important to consider the input-voltage-to-ground loop from an EMI perspective. A buck regulator steps down a higher DC voltage to a lower one by switching the connection to the supply on and off, resulting in high-side metal-oxide semiconductor field-effect transistor (MOSFET) (Q1) current, shown in Figure 2.

Figure 2: Input current waveform to a buck regulator

The MOSFET switches on and off rapidly, creating very sharp, almost discontinuous currents supplied by the input capacitor. Some devices, such as TI’s 3-A LMQ66430-Q1 and 6-A LMQ61460-Q1 36-V buck regulators, integrate high-frequency input capacitors inside the package, resulting in the smallest possible input current-loop area. Reducing the area of this input current loop results in smaller parasitic inductance at the input, which reduces the amount of electromagnetic energy emitted.

Integrated boot capacitor

Another high di/dt current loop that you should consider is the boot capacitor loop. The boot capacitor is responsible for supplying charge to the high-side MOSFET gate driver during the on-time. Internal circuitry refreshes this capacitor during the off-time. The source terminal of the high-side MOSFET connects to the switch node rather than GND. Referencing the boot capacitor to the source pin of the MOSFET ensures that the gate-to-source voltage (VGS) is high enough to turn on the MOSFET. With most buck regulators, you will have to leave some switch node area available on the board to connect the bootstrap capacitor, although this can be counterproductive when trying to minimize the area of the switch node for EMI. By integrating the boot capacitor inside the package, the LMQ66430-Q1 follows the two rules that I mentioned earlier, while also reducing the need for an external component.

Conclusion

It can be difficult to design compact power-supply designs capable of remaining under strict EMI limits. Buck regulators with integrated capacitors can make the process of EMI-compliant designs easier, while also helping reduce the overall external component count.

Related

Source: Texas Instruments

Recent Posts

Rubycon Extends Capacitance of Polymer Hybrid Aluminum Capacitors

16.7.2025
56

VINATech Partner with ONiO to Develop Batteryless IoT Power Architecture

16.7.2025
18

Knowles Releases Inductors for Mission-Critical RF Applications

15.7.2025
19

Bourns Unveils Smallest Automotive Grade Thick Film Resistors

14.7.2025
20

YAGEO Unveils Next Gen BMS Isolation Transformers

10.7.2025
21

Littelfuse Compact Tactile Switch Offers Low-Noise Switching and Dust Protection

10.7.2025
11

Murata Announces Mass Manufacturing of World’s First 0402 47µF MLCC

10.7.2025
45

Bourns Releases SMD Chip High-Power Metal Strip Current Sense Resistors in 2010 Case

10.7.2025
10

Vishay NTC Immersion Thermistor Delivers Fast Response in Liquid Cooled Automotive Systems

8.7.2025
14

Würth Elektronik Present Efficient Motor Controller Evaluation Kit

8.7.2025
32

Upcoming Events

Jul 23
13:00 - 14:00 CEST

PCB design for a Smartwatch

Jul 29
16:00 - 17:00 CEST

Impact of Elevated Voltage and Temperature on Molded Power Inductors in DC/DC converters

View Calendar

Popular Posts

  • Buck Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • Boost Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • Flyback Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • LLC Resonant Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • What is a Dielectric Constant and DF of Plastic Materials?

    4 shares
    Share 4 Tweet 0
  • Ripple Current and its Effects on the Performance of Capacitors

    3 shares
    Share 3 Tweet 0
  • Dual Active Bridge (DAB) Topology Explained

    0 shares
    Share 0 Tweet 0
  • How to Design an Inductor

    0 shares
    Share 0 Tweet 0
  • MLCC Case Sizes Standards Explained

    0 shares
    Share 0 Tweet 0
  • MLCC and Ceramic Capacitors

    0 shares
    Share 0 Tweet 0

Newsletter Subscription

 

Passive Components Blog

© EPCI - Leading Passive Components Educational and Information Site

  • Home
  • Privacy Policy
  • EPCI Membership & Advertisement
  • About

No Result
View All Result
  • Home
  • Knowledge Blog
  • Premium Suppliers

© EPCI - Leading Passive Components Educational and Information Site

This website uses cookies. By continuing to use this website you are giving consent to cookies being used. Visit our Privacy and Cookie Policy.
Go to mobile version