PIN DESCRIPTIONS AND FUNCTIONS

Steady state voltage range is 16 to 40 VDC. Transient range is 40

to 50 V for a maximum of 120 msec. Low voltage lockout prevents

the units from operating below approximately 15.5 VDC input

voltage to keep system current levels smooth, especially during

initialization or re-start operations. All models include a soft-start

function to prevent large current draw and minimize overshoot.

Internal 500 V capacitors are connected between the case and

input common and between the case and output common. See

Figure 1.

Interpoint’s FME filters are recommended to meet CE03 require-

ments for reflected input line current. When using an external

input filter it is important that the case of the filter and the case of

the converter be connected through as low as an impedance as

possible. Direct connection of the baseplates to chassis ground is

the best connection. If connected by a single trace, the trace

should be as wide as it is long.

Both single and dual output

models include a trim function.

Output voltage can be trimmed

from 60% up to 110% of nominal

V out . When trimming up, do not

exceed the maximum output

power. When trimming down, do

not exceed the maximum output

current.

On dual models the positive

output is regulated and the

negative output is transformer

coupled (cross-regulated) to the

positive output. When trimming

the duals, both output voltages

will be adjusted equally.

Two inhibit terminals disable switching, resulting in no output and

very low quiescent input current. The two inhibit pins allow access

to an inhibit function on either side of the isolation barrier to help

maintain isolation.

An open collector is

required for inter-

facing with both of

the

inhibit

pins.

Applying an open-

collector TTL logic

low to either inhibit

pin will inhibit the

converter. Applying

an open collector

TTL logic high or

leaving

the

pins

open will enable the converter. Inhibit 1 is referenced to Input

Common, while Inhibit 2 is referenced to Sense Return on the

output side.

The

open

circuit

voltage for Inhibit 1 is

13 V and for Inhibit 2 it

is 8 V. Float the inhibit

pin(s) if not used. The

required

logic

low

voltage level is 0.2 V

maximum.

Pin

Single Output

Dual Output

1

Positive Input

Positive Input

2

Input Common

Input Common

3

Trim

Case

4

Inhibit 1(INH1)

Inhibit 1(INH1)

5

Sync Out

Sync Out

6

Sync In

Sync In

7

Positive Output

Positive Output

8

Output Common

Output Common

9

Sense Return

Negative Output

10

Positive Sense

Trim

11

Share

Share

12

Inhibit 2 (INH2)

Inhibit 2 (INH2)

5

MOR SERIES

120 WATT

20 k

200

Ω

10 k

V

CC

Positive

Input

Inhibit 1

Input

Common

MOR Input Side

12 V

V

S

~

~

10 k

200

Ω

Current

Limit

Feedback

Voltage

E/A

Inhibit 2

Sense

Return

MOR Output Side

Positive Input

1

2 Input Common

MOR

Single or Dual

Output

10, 11, 12

7, 8, 9

Case*

Chassis Ground

Positive Input

1, 2, 3

4, 5, 6

28V

Input Common

FME28-461

EMI Filter

Positive Output

Output Common

3

Trim

7

10

9

8

Positive Output

Positive Sense

Sense Return

Output Common

MOR

Single

Output

TRIM UP

TRIM

DOWN

10 Trim

TRIM UP

TRIM DOWN

MOR

Dual

Output

7

8

9

Positive Output

Output Common

Negative Output

Trim Down:

α =

≤ α ≤ 1.0

50 •

α – 30

1 –

α

Trim Up:

α =

≤ α ≤ 1.1

(

– 1

(

α -1)

2.5

– 50

Trim Formulas