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MDC_ICF_A01 Page 8 of 16

ICF Series

Wide Input 1000 Watt Isolated Full Brick DC-DC

Safety Requirements

Basic Insulation is provided between input and the output. The

converters have no internal fuse. To comply with safety agencies

requirements, a fast-acting or time-delay fuse is to be provided in

the unearthed lead. Recommended fuse values are:

a)

140A for 9V<Vin<18V

b)

90A for 18V<Vin<36V.

Electromagnetic Compatibility (EMC)

EMC requirements must be met at the end-product system level,

as no specific standards dedicated to EMC characteristics of board

mounted component dc-dc converters exist.

With the addition of a two stage external filter, the ICF converters

will pass the requirements of MILSTD-461F CE102 Base Curve for

conducted emissions. Note that 5uH LISN should be used in order

to enable operation of the converter at low input voltage.

Remote Sense Pins (Pins 10 and 11)

Sense inputs compensate for output voltage inaccuracy delivered

at the load.

Fig. 2: Circuit configuration for Remote sense function.

The sense input and power Vout pins are internally connected

through 100Ω (SENSE+ to +OUT) and 10 Ω (SENSE- to –OUT)

resistors enabling the converter to operate without external

connection to the Sense. If the Sense function is not used for

remote regulation, the user should connect SENSE- (Pin 10) to –

OUT (Pins 8 and 9) and SENSE+ (Pin 11) to +OUT (Pins 5 and 6) at

the converter pins.

Sense lines must be treated with care in PCB layouts and should

run adjacent to DC signals. If cables and discrete wiring is used, it

is recommended to use twisted pair, shielded tubing or similar

techniques.

The maximum voltage difference between Sense inputs and

corresponding power pins should be kept below 1V, i.e.:

V(SENSE+) - V(+OUT) ≤ 1V

V(-OUT) – V(SENSE-) ≤ 1V

Note that maximum output power is determined by maximum

output current and highest output voltage at the output pins of

the converter:

[V(+OUT) – V(-OUT)]x Iout ≤ Pout rated

Output Voltage Adjust/TRIM (Pin 12)

The TRIM (Pin 12) allows user to adjust output voltage 10% up or -

40% down relative to rated nominal voltage by addition of external

trim resistor. Trim resistor should be mounted close to the

converter and connected with short leads. Internal resistor in the

converter used for the TRIM is high precision 0.1% with

trimming is not used, the TRIM pin should be left open.

Trim Down – Decrease Output Voltage

Trimming down is accomplished by connecting an

external

(pin 10), with a value of:

[kΩ]

Where,

[V]

[V]

∆ =

(

)

(

)

(

)

[%]

Fig. 3: Circuit configuration for Trim-down function

To trim the output voltage 10% (∆=10) down, required external

trim resistance is:

= 39.92 k