s-8551 Seiko Instruments Inc., s-8551 Datasheet - Page 19

• Manufacturer Part Number: s-8551
• Description: Step-down, Built-in Fet, Synchronous Rectification, Pwm Control Switching Regulators
• Manufacturer: Seiko Instruments Inc.

STEP-DOWN, BUILT-IN FET, SYNCHRONOUS RECTIFICATION, PWM CONTROL SWITCHING REGULATORS
Rev.2.1
Reference Data
1. Reference data for external parts
Caution The values of the external parts are based on the materials provided by each manufacturer. However,
2. Output current (I
Inductor
Input capacitor
Output capacitor
2. 1 V
2. 2 V
Element Name
(1)
(1)
100
100
90
80
70
60
50
40
30
20
10
90
80
70
60
50
40
30
20
10
_01
Output current (I
0
Output current (I
0
OUT
OUT
consider the characteristics of the original materials when using the above products.
0
0
= 1.1 V (R
= 1.8 V (R
V
V
V
V
V
V
IN
IN
IN
IN
IN
IN
= 2.0 V
= 3.6 V
= 5.5 V
= 2.2 V
= 3.6 V
= 5.5 V
OUT
) vs. Efficiency (η) Characteristics and Output current (I
1
1
NR4018T3R3M
C3216X7R1E475K
C3216X7R1C106K
FB1
FB1
Product Name
= 36 kΩ, R
= 36 kΩ, R
OUT
I
OUT
I
OUT
OUT
10
10
) vs. Efficiency (η)
) vs. Efficiency (η)
[mA]
[mA]
FB2
FB2
100
100
= 43 kΩ)
= 18 kΩ)
Properties of External Parts
Seiko Instruments Inc.
Taiyo Yuden Co., Ltd
1000
1000
TDK Corporation
TDK Corporation
Manufacture
(2) Output current (I
(2) Output current (I
1.3
1.2
1.1
1.0
0.9
2.0
1.9
1.8
1.7
1.6
0
0
OUT
V
V
3.3 µH, DCR
V
V
V
V
IN
IN
IN
IN
IN
IN
) vs. Output voltage (V
= 5.5 V
= 5.5 V
= 3.6 V
= 2.0 V
= 3.6 V
= 2.0 V
1
1
OUT
OUT
Characteristics
) vs. Output voltage (V
) vs. Output voltage (V
MAX
I
I
OUT
OUT
S-8550/8551 Series
10
10
4.7 µF
= 0.07 Ω, I
10 µF
[mA]
[mA]
OUT
100
100
) Characteristics
MAX
= 1.23 A
1000
1000
OUT
OUT
)
)
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