Linear DC1123, LTC3562 DC1123 QUICK START GUIDE , A PPL ICA TION INFORM A TION

DC1123 QUICK START GUIDE

17.

Set Load1 and Load2 to 450mA. S et Load3 and

Load4 to 300mA. Adjust PS1 over the operating range

and observe line regulation.

A PPL ICA TION INFORM A TION

This demo circuit is designed to demonstrate the full

capability of the LTC3562 I

C Q uad Synchronous

Step-Down DC-DC Regulator. Not all components are

required in all applications. The critical circuit com-

ponents are on the top of the board near the IC and

listed in the Required C ircuit Components section of

the Bill of M aterials, in Figure 5.

The input capacitor netw ork of C1 and R1 is used to

dampen source lead inductances that commonly oc-

cur in laboratory setups with tw isted leads and a

bench pow er supply. W hen using a USB cable this

input damping netw ork w ill likely not be required.

Please note that the in-circuit capacitance of the

specified 10uF, 0805 ceramic capacitor for C1 and C2

is less than 5uF each with VIN greater than 4.25 Volts.

For good transient response and stability the output

capacitor each buck regulator should retain at least

4uF of capacitance over the operating temperature

and voltage range.

The output inductors for the OUT600A and OU T600B

are the recommended values of 3.3uH w hile the

OUT400A and OUT400B are 4.7uH.

Resistors R 4 and R 6 are to adjust the output voltage

seen on the OUT600A output while R 3 and R4 w ill set

the voltage on the OU T400A output.