ZXLD1356Q

Document number: DS37077 Rev. 2 - 2

21 of 28

www.diodes.com

October 2015

© Diodes Incorporated

ZXLD1356Q

Q

Figure 3. ZXLD1356Q Minimum Recommended Inductor

Diode Selection

For maximum efficiency and performance, the rectifier (D1) should be a fast low capacitance Schottky diode* with low reverse leakage at the

maximum operating voltage and temperature.

They also provide better efficiency than silicon diodes, due to a combination of lower forward voltage and reduced recovery time.

It is important to select parts with a peak current rating above the peak coil current and a continuous current rating higher than the maximum

output load current. It is very important to consider the reverse leakage of the diode when operating above +85°C. Excess leakage will increase

the power dissipation in the device and if close to the load may create a thermal runaway condition.

The higher forward voltage and overshoot due to reverse recovery time in silicon diodes will increase the peak voltage on the LX output. If a

silicon diode is used, care should be taken to ensure that the total voltage appearing on the LX pin including supply ripple, does not exceed the

specified maximum value.

*A suitable Schottky diode would be PDS3100Q (Diodes Inc).

Minimum R ecommended Inductor

2% Accuracy, <60°C Case Temperature

0

10

20

30

40

50

60

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

Supply Voltage (V)

Legend

68uH

100uH

150uH

220uH