LTC3589_1 Datasheet, PDF (26/46 Pages) Linear Technology – 8-Output Regulator with Sequencing and I2C

LTC3589
OPERATION
Table 10. Inductors for Buck-Boost Switching Regulator
MANUFACTURERS
PART
NUMBER
VALUE
(µH) DCR (Ω)
Coilcraft
XPL4020-152ML
XPL4020-222ML
XPL4020-332ML
LPS6225-332ML
LPS6225-472ML
1.5
0.036
2.2
0.060
3.3
0.085
3.3
0.055
4.7
0.065
Cooper
SD14-1R5-R
SD14-2R0-R
SD14-2R5-R
SD14-3R2-R
SD25-3R3-R
1.5
0.039
2.0
0.045
2.5
0.060
3.2
0.066
3.3
0.038
Sumida
CDRH5D16NP-3R3N
3.3
0.045
CDRH5D16NP-4R7N
4.7
0.064
TDK
VLF5014ST-2R2N2R3 2.2
0.073
VLCF5020T-2R7N2R2-1 2.7
0.083
VLCF5020T-3R3N2R0-1 3.3
0.096
TOKO
1124BS-1R8N
1124BS-3R3N
1.8
0.056
3.3
0.074
Tokin
H-DI-0520-3R3
H-DI-0630-3R8
3.3
0.062
3.8
0.040
Wurth
744052002
7440420027
744053003
7440530047
2.5
0.030
2.7
0.047
3.0
0.024
4.7
0.030
MAX DC
CURRENT (A)
3.60
2.60
2.40
3.50
3.00
2.91
2.56
2.29
2.00
2.21
2.60
2.05
2.3
2.2
2
2.70
2.10
2.00
2.00
2.4
2.2
2.8
2.4
SIZE (mm) W × L × H
4.2 × 4.2 × 2.0
4.2 × 4.2 × 2.0
4.2 × 4.2 × 2.0
6.0 × 6.0 × 2.0
6.0 × 6.0 × 2.0
5.2 × 5.2 × 1.45
5.2 × 5.2 × 1.45
5.2 × 5.2 × 1.45
5.2 × 5.2 × 1.45
4.8 × 4.8 × 2.5
5.6 × 5.6 × 1.8
5.6 × 5.6 × 1.8
4.8 × 4.6 × 1.4
5.0 × 5.0 × 2.0
5.0 × 5.0 × 2.0
4.5 × 4.7 × 1.8
4.5 × 4.7 × 1.8
5.3 × 5.3 × 2.0
6.3 × 6.3 × 3.0
5.8 × 5.8 × 1.8
4.8 × 4.8 × 1.8
5.8 × 5.8 × 2.8
5.8 × 5.8 × 2.8
ensure that the inductor does not saturate during normal
operation. If output short-circuit is a possible condition,
the inductor should be rated to handle the maximum peak
current specified for the buck-boost converter. Table 9
shows several inductors that work well with the LTC3589
buck-boost regulator.
Capacitor Selection
Low ESR ceramic capacitors should be used at both the
output and input supply of the buck-boost switching
regulator. Only X5R or X7R ceramic capacitors should
be used because they retain their capacitance over wider
voltage and temperature ranges than other ceramic types.
A 22µF capacitor is sufficient for the buck-boost switch-
ing regulator output. For good transient response and
stability the output capacitor should retain at least 10µF of
capacitance over operating temperature and bias voltage.
Place at least 4.7µF decoupling capacitance as close as
possible to PV_IN4 pin. Refer to Table 11 for recommended
ceramic capacitor manufacturers.
Table 11. Ceramic Capacitor Manufacturers
AVX
www.avxcorp.com
Murata
www.murata.com
Taiyo Yuden
www.t-yuden.com
Vishay Siliconix
www.vishay.com
TDK
www.tdk.com
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