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dc2721abf

DEMO MANUAL

DC2721A-B

QUICK START PROCEDURE

Demonstration circuit 2721A-B is an easy way to evaluate

the performance of the LTM4625EY. Please refer to Figure

1 for test setup connections and follow the procedure

below.

1.With power off, place the jumpers in the following posi-

JP7

JP5

JP1

RUN

MODE

ON

CCM

–0.9V

2.Before connecting input supply, load and meters, pre-

set the input voltage supply to be between 4V to 15V.

Preset the load current to 0A.

3.With power off, connect the load, input voltage supply

and meters as shown in Figure 1.

4.Turn on input power supply. The output voltage meter

should display the selected output voltage ± 2%.

5.Once the proper output voltage is established, adjust

the load current within the 0A to 3A range and observe

the load regulation, efficiency, and other parameters.

Output voltage ripple should be measured across C12

with a BNC cable terminated into 50Ω and an oscil-

loscope.

6.To observe increased light load efficiency place the

mode pin jumper (JP5) in the DCM position.

7.Level shifting circuits are provided for PGOOD, CLKIN

and RUN signals. The CLKIN turret E6 can be connected

to a ground referenced clock with amplitude up to 3.3V

for optional external clock synchronization. The PGOOD

turret E8 provides a ground referenced 3.3V PGOOD

signal.

8.Note that CLKOUT and TRACK signals are not level

shifted and are referenced to –VOUT. If ground refer-

enced CLKOUT output and TRACK input signals are

desired, external level shifting circuits for these pins

are necessary.