AAT1121
1.5MHz, 250mA Step-Down Converter
Output Voltage
VOUT (V)
R2 = 59kΩ
R1 (kΩ)
R2 = 221kΩ1
R1 (kΩ)
L1 (µH)
1.5
1.5
1.5
1.5
1.5
1.5
1.5
2.2
2
0.6
—
—
75
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.8
1.85
2.0
2.5
3.3
19.6
29.4
39.2
49.9
59.0
68.1
78.7
88.7
118
124
137
187
267
113
150
187
221
261
301
332
442
464
523
715
1000
2.7
3.0/3.3
3.0/3.3
3.0/3.3
3.9/4.2
5.6
Table 3: Evaluation Board Component Values.
Inductance
(µH)
Max DC
DCR
Size (mm)
LxWxH
Manufacturer
Part Number
Current (mA)
(mΩ)
Type
Sumida
Sumida
Sumida
Sumida
Sumida
Sumida
Sumida
Sumida
Sumida
Sumida
Sumida
Taiyo Yuden
Taiyo Yuden
Taiyo Yuden
Taiyo Yuden
FDK
CDRH2D09-1R5
CDRH2D09-2R2
CDRH2D09-2R5
CDRH2D09-3R0
CDRH2D09-3R9
CDRH2D09-4R7
CDRH2D09-5R6
CDRH2D11-1R5
CDRH2D11-2R2
CDRH2D11-3R3
CDRH2D11-4R7
NR3010
1.5
2.2
2.5
3
730
600
530
470
450
410
370
900
780
600
500
1200
1100
870
750
1200
1100
1000
900
88
115
135
150
180
230
260
54
78
98
135
80
95
140
190
90
100
120
140
3.0x3.0x1.0
3.0x3.0x1.0
3.0x3.0x1.0
3.0x3.0x1.0
3.0x3.0x1.0
3.0x3.0x1.0
3.0x3.0x1.0
3.2x3.2x1.2
3.2x3.2x1.2
3.2x3.2x1.2
3.2x3.2x1.2
3.0x3.0x1.0
3.0x3.0x1.0
3.0x3.0x1.0
3.0x3.0x1.0
3.2x2.6x0.8
3.2x2.6x0.8
3.2x2.6x0.8
3.2x2.6x0.8
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Shielded
Chip shielded
Chip shielded
Chip shielded
Chip shielded
3.9
4.7
5.6
1.5
2.2
3.3
4.7
1.5
2.2
3.3
4.7
1.5
2.2
3
NR3010
NR3010
NR3010
MIPWT3226D-1R5
MIPWT3226D-2R2
MIPWT3226D-3R0
MIPWT3226D-4R2
FDK
FDK
FDK
4.2
Table 4: Suggested Inductors and Suppliers.
1. For reduced quiescent current, R2 = 221kΩ.
2. R2 is opened, R1 is shorted.
1121.2007.03.1.2
17
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
