Inductors (Coils)

Product Overview Power Inductor VLS Series

Power Inductor VLS SeriesThe VLS series power inductors are magnetic shield (resin) type wound inductors that have been developed taking full advantage of the material technology and manufacturing processes that TDK have accumulated so far. This type of inductors can largely be classified into three categories: VLS-HBX/HBU series, VLS-CX series, and VLS-EX/AF/EX-H series; and they show respective excellent features. This article introduces the structure, features, and application purposes of these products, and other information that helps you in an easy-to-understand way.

Product summary

VLS-HBX/HBU series are the wire-wound type inductors that use metallic magnetic material as their cores. VLS-CX series and VLS-EX/AF/EX-H series are also wire-wound type inductors but they use ferrite material as their cores.
Each product in these series reduces magnetic flux leakage by covering the wire winding part with resin in which magnetic material is mixed.

Figure 1: Product summary
Series
Product summary

Magnetic shield type wound inductors that use metallic magnetic material

These inductors use metallic magnetic material to achieve larger current and low Rdc. They have been developed pursuing simple product structure. The magnetic flux leakage is reduced by covering the wire winding by resin in which magnetic material is mixed.
The manufacturing processes of these inductors are automated and the products are not touched by humans during being processed; which means that high quality and high productivity are realized at the same time.

Magnetic shield type wound inductors that use ferrite material

By optimizing the core shape of the conventional products, these inductors have superior electrical characteristics than the conventional ones. They have been developed pursuing simple product structure. The magnetic flux leakage is reduced by covering the wire winding by resin in which magnetic material is mixed.
The manufacturing processes of these inductors are automated and the products are not touched by humans during being processed; which means that high quality and high productivity are realized at the same time.

Magnetic shield type wound inductors that achieve larger current and lower resistance

With ferrite magnetic material and optimum structural design, these power inductors achieve larger current and lower Rdc.
The processes from the production of cores to finishing the coil take place in the same plant to make the lead time shorter. Also, stable manufacturing is enabled by automated production line.

Features
  • Larger current and low resistance are achieved by using metallic magnetic material.
  • The magnetic shield structure enables high-density mounting.
  • High quality and high productivity, and therefore stable supply is possible.
  • HBU series are designed for boost circuits such as back panels.
  • By optimizing the core shape, larger current and lower resistance compared to conventional products are achieved.
  • High voltage specifications are achieved by using ferrite magnetic material.
  • The magnetic shield structure enables high-density mounting.
  • High quality and high productivity, and therefore stable supply is possible.
  • Larger current and lower resistance compared to conventional products are achieved with optimum structural design.
  • The magnetic shield structure enables high-density mounting.
  • High quality and high productivity, and therefore stable supply is possible.
  • AF series is designed for sound quality improvement applications.
  • EX-H series is designed for automotive applications.
Applications
  • Smart phones, tablet terminals
  • Other mobile devices
  • Smart phones, tablet terminals
  • Other mobile devices
  • TV, STB, gaming equipment
  • Other AV equipment
  • in-vehicle infotainment

Product structures

The structures of the VLS series products can largely be classified into two types. VLS-HBX/HBU series and VLS-CX series employ terminal electrode structure to reduce size and thickness. VLS-EX/AF/EX-H series are the middle-sized products of 5 mm or 6 mm, which employ metal terminals.

Figure 2: Product structures
Series
VLS-HBX series VLS-HBU seriesVLS-HBX series
VLS-HBU series
VLS-CX seriesVLS-CX series
VLS-EX series VLS-AF series VLS-EX-HseriesVLS-EX series
VLS-AF series
VLS-EX-H series
Product structures VLS-HBX series VLS-HBU series VLS-CX series VLS-EXseries VLS-AF series VLS-EX-H series

Product features

Figure 3 shows the features of each VLS series. VLS-HBU series achieves high withstand voltage by coating the metal core. VLS-EX-H series is designed for automotive applications with permissible operating temperature as high as 125°C.

Figure 3: List of product features
Series VLS-HBX series VLS-HBU series VLS-CX series VLS-EX series VLS-AF series VLS-EX-H series
Appearance VLS-HBX series VLS-HBU series VLS-CX series VLS-EX series VLS-AF series VLS-EX-H series
Operating
temperature
range
-40 to 105°C
(including self-temperature rise)
-40 to 105°C
(including self-temperature rise)
-40 to 105°C
(including self-temperature rise)
-40 to 125°C
(including self-temperature rise)
Core Metal Metal + coating Ferrite Ferrite
External coating External resin coating with metallic magnetic powder mixed in External resin coating with metallic magnetic powder mixed in External resin coating with ferrite magnetic powder mixed in
Terminal electrode specifications Silver electrode + plating Silver electrode + plating Metal terminal + plating
Printing display
/ Printing method
Polarity
/ Laser
Polarity
/ Laser
Polarity + L value
/ Laser
L value
/ Laser
Polarity + L value + Production code
/ Laser
Features Standard specifications High withstand voltage specifications with coated metal core High withstand voltage specifications with ferrite core Standard specifications Sound quality improvement specifications Automotive gradeAutomotive application specifications

Applications

Figure 4 shows which VLS series is optimum for which application circuit. VLS-HBU series is suitable for step-up type DC-DC converters and VLS-AF series is suitable for low-pass filter circuits for class-D amplifiers.

Figure 4: Applications and suitable products
Applications DC-DC converter (Step-down type) DC-DC converter (Step-up type) Low-pass filter for class-D amplifiers
DC-DC converter (Step-down type) DC-DC converter (Step-up type) Low-pass filter for class-D amplifiers
Product series  VLS-HBX, VLS-CX, VLS-EX, VLS-EX-H    VLS-HBU    VLS-AF

List of products

Figure 5 shows the list of products by series and by shape. You can view the detailed information of the product or purchase a sample by clicking the type name.

Figure 5: List of products
  • Commercial gradeCommercial grade
  • Automotive gradeAutomotive grade
Size
(mm)
Height
(mm)
VLS-HBX series VLS-HBU series VLS-CX series VLS-EX series VLS-AF series VLS-EX-H series
2.0x1.6 1.0 Max. VLS201610HBX-1VLS201610HBX-1   VLS201610CX-1VLS201610CX-1      
1.2 Max. VLS201612HBX-1VLS201612HBX-1   VLS201612CX-1VLS201612CX-1      
2.5x2.0 1.0 Max. VLS252010HBX-1VLS252010HBX-1 VLS252010HBUVLS252010HBU VLS252010CX-1VLS252010CX-1      
1.2 Max. VLS252012HBX-1VLS252012HBX-1 VLS252012HBUVLS252012HBU VLS252012CX-1VLS252012CX-1      
3.0x3.0 1.2 Max. VLS3012HBXVLS3012HBX   VLS3012CX-1VLS3012CX-1      
4.0x4.0 1.2 Max. VLS4012HBXVLS4012HBX          
5.0x5.0 4.5Max.       VLS5045EXVLS5045EX    
6.0x6.0 4.5Max.       VLS6045EXVLS6045EX VLS6045AFVLS6045AFD-Amp LPF VLS6045EX-HVLS6045EX-HAutomotive (125°C)

What are power inductors?

Power inductors are inductors used for power supply circuit such as DC-DC converters. They are also called power coils or power chalks. One of the inductors' characteristics is that they store energy by self-induction function. Chopper type DC-DC converters use inductors having such characteristics with switching devices for voltage conversion (see Figure 6).
Depending on the processing method, inductors can be classified into multilayer type, thin-film type, and wire-wound type. Since wire-wound type permits large current to flow, most of the power inductors are wire-wound type. Various wound-type power inductor products with ferrite or soft magnetic metal core are offered. Recently, the multilayer type and thin-film type, with which reduction of size and thickness can be achieved, are being improved to allow for larger current.

Figure 6: DC-DC converter (chopper type / step-down type) and inductor

The voltage is dropped to a desired level in accordance with the duty ratio (the ratio that indicates how long the switch is ON during the switching cycle) setting.

Switching
repeated