Table 2: AAT1106 EVAL Bill of Materials.

Output Voltage

The board has an R1 value of 316kΩ. To adjust the output from the 1.8V default, select R2 according to Table

3 or use the jumper JP2. A smaller value resistor divider can be used for better noise immunity, values are

shown in column 3. A larger value resistor divider is used as default for lower current consumption. Standard

1% resistor values are substituted for calculated values.

Table 3: Resistor Selection for Adjustable Output Voltage.

Component

Part Number

Description

Manufacturer

U1

AAT1106

1.5 MHz, 600mA Synchronous

Analogic Tech

Step-Down Converter

L1

SF32-2R2M-R

Inductor 2.2UH 1.8A SMD

Fenfa

C1

GRM42-6X7R475K16PT

Cap Ceramic 4.7µF16V X7R 10% 1206

Murata

C2

C1005COG1H220JT000P

Cap Ceramic 22pF 50V C0G 5% 0402

TDK

C3

GRM31BR71C106KA01L

Cap Ceramic 10µF 16V X7R 10% 1206

Murata

R1, R2A

Chip Resistor

Resistor 316KΩ 1/16W 1% 0402 SMD

R2B

Chip Resistor (optional)

Resistor 470kΩ 1/16W 1% 0402 SMD

R2C

Chip Resistor (optional)

Resistor 634KΩ 1/16W 1% 0402 SMD

R2D

Chip Resistor (optional)

Resistor 1MΩ 1/16W 1% 0402 SMD

No Designator

SM6T6V8A (optional)

6.8V TVS

ST

R1 = 316kΩ

R1 = 59kΩ

R1 = 316kΩ

R1 = 59kΩ

V

R2 (kΩ)

R2 (kΩ)

V

R2 (kΩ)

R2 (kΩ)

0.6

0(short)

0(short)

0.6

0(short)

0(short)

0.80

105

19.6

1.90

681

127

1.00

210

39.2

2.00

732

137

1.20

316

59.0

2.10

787

147

1.30

365

68.1

2.20

845

158

1.40

422

78.7

2.32

909

169

1.50

475

88.7

2.40

953

178

1.60

523

97.6

2.50

1000

187

1.70

576

107

3.30

1430

267

1.80

634

118

EV138

AAT1106 EVAL:

600mA Step-Down Converter

6

EV-138.2007.08.1.0