tech.support@psbel.com

belfuse.com/power-solutions

BCD20009-G Rev F, 20-Nov-2020

Page 11 of 16

IMX35 Series

35 Watt Quad-Output DC-DC Converter

© 2020 Bel Power Solutions & Protection

Shutdown

The outputs of the converters may be enabled or disabled by means of a logic signal (TTL, CMOS, etc.) applied to shutdown (pin 8).

If the shutdown function is not required, pin 8 should be left open-circuit:

Converter operating:

2.0 to 20 V

Converter disabled:

–10 to +0.7 V

Progr. Input Undervoltage Lockout PUL

A special feature of the converter (with Rev. BA or later) is the adjustable undervoltage lockout protection, which protects the

converter (and the system) from high current caused by operation at low input voltages. This ensures easier start-up in distributed

power systems.

The table below shows the band of switch on/off and the hysteresis.

Table 9: Trigger level and hysteresis (pin 1 left open)

Model

Trigger level

Hysteresis

Unit

20IMX35

7 to 8

<0.5

V

40IMX35

14 to 15.5

<1

70IMX35

31 to 34

<3

110IMX35

42 to 50

< 8

The undervoltage lockout levels may be programmed by using an external resistor R

preset levels as specified in table 10.

Table 10: Typical values for R

20IMX35

40IMX35

R

V

R

V

∞

≤8

∞

≤15.5

39

10

43

22

19

12

16

26

13

14

10

28

9.1

16

0

32

70IMX35

110IMX35

R

V

R

V

∞

31

∞

42

270

40

270

50

110

50

120

60

80

55

51

75