ADVANCED INFORMATION
COIL CONSIDERATIONS
TK654xx
There are several issues to consider when choosing the proper coil for the TK654xx Step-Down Converter.
An important consideration is the coil manufacturer. Toko Inc. has been in the coil business for many years and has been
a leader in this market with high quality of product, low cost, and high volume delivery distribution.
The test circuit in this data sheet uses the D10F type series for its low resistance (0.27 Ω for 100 µH). This coil should
be considered when the user is interested in high efficiency.
TYPE D10F
For Reflow Soldering
Frequency Range: 1 kHz ~ 1 MHz
Inductance Range: 10 ~ 1500 µH
Unit:mm
Amajorissuetodayisspaceaswellasheight. Tokomakesalowprofilesurfacemountcoilserieswhichmayaccomodate
this requirement. The D52 series dimensions are shown below. The 100 µH coil has a maximum rated DC resistance
of 1.6 Ω.
TYPE D52FU
Frequency Range: 1 kHz ~ 2 MHz
Inductance Range: 100 µH ~ 6800 µH
FEATURES
• Low profile (2.0 mm typ. height) and 5 mm square
• Magnetically shielded version, unshielded also available
• Available on tape and reel for auto insertion
• Suitable for reflow soldering
September 1999 TOKO, Inc.
Page 17
TOKO [ TOKO, INC ]
