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BCD.00002 Rev AJ, 28-May-2018

Page 4 of 17

IMX70 / IMY70 Series

70 to 90 Watt DC-DC Converters

© 2018 Bel Power Solutions & Protection

Electrical Input Data

General conditions:

- T

Table 2: Input data

Model

24IMX70

110IMY70

Unit

Characteristics

Conditions

min

typ

max

min

typ

max

V

i

Operating input voltage

T

33.6

50

137.5

VDC

V

i nom

Nominal input voltage

24

(72, 96), 110

V

i 2s

Temporary input voltage

For 2 s, no shutdown

40.1

154

V

i sur

Repetitive surge voltage

Shutdown, no damage

50

168

t

start-up

Converter

start-up time

Switch on

Worst case condition at

V

500

250

500

ms

SD high

500

500

t

rise

Rise time

V

25

25

I

i o

No-load input current

I

200

25

50

mA

I

irr

Reflected ripple current

I

30

200

mA

pp

I

inr p

Inrush peak current

V

25

35

A

C

i

Input capacitance

For surge calculation

24

7.7

µF

V

SD

Shutdown voltage

Converter disabled

– 0.7 to +0.7

– 0.7 to +0.7

V

Converter operating

2 to 20 (or open-circuit)

2 to 20 (or open-circuit)

I

SD

Shutdown pin current

– 0.2

– 0.2

mA

I

i SD

Input current at shutdown

V

2

2

f

s

Switching frequency

V

kHz

1

V

proportionately increased.

2

Typ. 240 kHz for single-output models, typ. 300 kHz for models with 5 V output

Inrush Current

The inrush current has been kept as low as possible by choosing a very small input capacitance. A series resistor may be installed

in the input line, in order to further reduce this current.

t

JM028

0

20

40

60 µs

40

30

20

10

A

t

04008b

Fig. 3

Inrush current at V

Source impedance according to ETS 300132-2: L = 10 μH,

R = 1.5 Ω.

Fig. 4

Converter start-up and rise time