MT/MS Series Amorphous Saturable Cores0 pages

1 . Saturable Cores for Mag-

The Mag-amp method is one of the few different output voltage regulation methods used in switching power

supplies. A saturable core is used in the secondary side of the main transformer to regulate voltage by

magnetic pulse width modulation (PWM). The Mag-amp method is especially effective and economically

attractive in low voltage/high current circuits and is frequently used in power supplies for information

processing equipment, such as desktop PCs and computer servers; in power supplies for office equipment,

such as photocopy machines and printers, and in power supplies for communication equipment, such as

mobile phone stations.

Miniaturization, high efficiency, low noise, high reliability, and high precision can be easily realized by adopting

the Mag-amp method.

Utilizing the unique magnetic characteristics of cobalt-based amorphous alloys, we have realized low loss at

high frequencies, which cannot be realized using other materials. Our lineup consists of MS series cores,

which are well suited for general purpose applications, and MT cores, which have lower loss than the MS

series.

Mag-Amp

Basic Circuit Diagram of Mag-Amp method

Basic Characteristics (Typical Value)

B[T]

30

CD

iu 20

Q

E

2 io

p

8 0

0.0

2.0

0.5 1.0 1.5

Output current lo[A]

Comparison of Core Temperature Rise in a Power Supply

0.6

100,000

CO

E

10.000

-300 -200

200 300

H[A/m]

CO

cn

o

—i

8

o

o

1,000

-0.6

B-H Curve (500kHz, RT)

100

100

Frequency [kHz]

Core Loss

1,000

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