VIN

EN

RESET

VCC

SYNC

FPWM

AGND

PGND

SW

CBOOT

FB

BIAS

LM53603

L

3x 10µF

3x 22µF

2.2 µH

0.47 µF

0.1 µF

3 Ÿ

3.3 µF

µC

100 kŸ

6V to 36V

3.3V or 5V

3A

10nF

Copyright © 2016, Texas Instruments Incorporated

19

LM53602, LM53603

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SNVSAR0 – NOVEMBER 2016

Product Folder Links: LM53602 LM53603

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Copyright © 2016, Texas Instruments Incorporated

Typical Applications (continued)

Figure 16. Full-Featured Industrial Power Supply Schematic

9.2.1.1 Design Parameters

There are a few design parameters to take into account. Most of those choices decide which version of the

device to use. The desired output current steers the designer toward a LM53602 type or LM53603 type part. If

the output voltage is 3.3 V or 5 V, a fixed output version of the device can be used. Any other voltage level within

the tolerance of the part can be achieved by using an adjustable version of the device. Most but not all

parameters are independent of the of the IC choice. The output filter components (inductor and output

capacitors) might vary with the choice of output voltage, especially for output voltages higher than 5 V. See

Detailed Design Procedure for help in choosing these components.

Table 2. Design Parameters

DESIGN PARAMETER

EXAMPLE VALUE

Input voltage

12 V

Output voltage

5 V

Maximum output current

3 A

9.2.1.2 Detailed Design Procedure

The following detailed design procedure applies to Figure 15, Figure 16, and Figure 45.

9.2.1.2.1

Setting the Output Voltage

For the fixed output voltage versions, the FB input is connected directly to the output voltage node. Preferably,

near the top of the output capacitor. If the feed-back point is located further away from the output capacitors (that

is, remote sensing), then a small 100-nF capacitor may be needed at the sensing point.

For output voltages other than 5 V or 3.3 V, a feedback divider is required. For the ADJ version of the device, the

regulator holds the FB pin at 1 V. The range of adjustable output voltage can be found in the Recommended