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Pin Descriptions

+Vin:

The positive input supply for the module with

telecom central office supply, this input is connected

to the primary system ground.

–Vin:

The negative input supply for the module, and

the 0VDC reference for the EN 1, EN 2, TEMP, and

AUX signals. When the module is powered from a

+24V supply, this input is connected to the 24V Return.

EN 1:

The negative logic input that enables the

module output. This pin is TTL compatible and

module’s outputs. A logic ‘1’ or high impedance

disables the module’s outputs. If not used, the pin

EN 2:

The positive logic input that enables the

module output. This pin is TTL compatible and

enables the module’s outputs. If not used, the pin

should be left open circuit.

TEMP:

This pin produces an output signal that tracks

the module’s metal case temperature. The output

10mV/°C from an intital value of 0.1VDC at -40°C

whenever the module is supplied with a valid input

voltage, and is independant of the enable logic status.

Ω will adversly

affect the module’s over-temperature shutdown threshold.

Use a high-impedance input when monitoring this

signal.)

AUX:

Produces a regulated output voltage of 11.6V

from the pin must be limited to 10mA. The voltage

may be used to indicate the output status of the

module to a primary referenced circuit, or power a

low-current amplifer.

The higher regulated output voltage, which is

referenced to the COM node.

The lower regulated output voltage, which is

referenced to the COM node.

COM:

The secondary return reference for the module’s

two regulated output voltages. It is DC isolated from

the input supply pins.

to be adjusted higher or lower than the preset value.

If not used, this pin should be left open circuit.

to be adjusted higher or lower than the preset value.

If not used, this pin should be left open circuit.

On/Off Logic

Pin 3

Pin 4

Output Status

1

×

Off

01

On

×

0

Off

Pin-Out Information

Pin

Function

1+Vin

2-Vin

3

EN 1

4

EN 2

5

TEMP

6

AUX

7

Do Not Connect

8

Do Not Connect

Pin

Function

10

11

12

13

14

COM

15

COM

16

COM

17

COM

18

COM

Notes:

Logic 1 =Open collector

Logic 0 = –Vin (pin 2) potential

For positive Enable function, connect pin 3

to pin 2 and use pin 4.

For negative Enable function, leave pin 4

open and use pin 3.

Note: Shaded functions indicate signals that are

referenced to the input (-Vin) potential.

Pin

Function

19

COM

20

21

+Vo

2

22

+Vo

2

23

+Vo

2

24

+Vo

2

25

Do Not Connect

26

Do Not Connect

PT4680 Series

20-A 24-V Input Dual Output

Isolated DC/DC Converter