Not Recommended for New Designs

PTB48510

PTB48511

SLTS219F – FEBRUARY 2004 – REVISED MARCH 2007

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DEVICE INFORMATION

TERMINAL FUNCTIONS

TERMINAL

DESCRIPTION

NAME

NO.

(1)

1

a –48 V telecom central office supply, this input is connected to the primary system ground.

This pin is used when the PTB4851x and PTB4850x DC/DC converter modules are used together. Connecting

Sync In

2

this pin to the Sync Out of the PTB4850x module allows the PTB4851x to be synchronized to the same switch

conversion frequency as the PTB4850x.

This is an open-collector (open-drain) negative logic input that enables the module output. This pin is

3

Note: Connecting this input directly to the EN Out pin of the PTB4850x enables the output voltages from both

converters (PTB4850x and PTB4851x) to power up in sequence.

The negative input supply for the module, and the 0 VDC reference for the Enable, and Sync In signals. When

4

the module is powered from a +48-V supply, this input is connected to the 48-V Return.

5

8

The secondary return reference for the module's regulated output voltages. This node is dc isolated from the

COM

6

input supply pins.

7

or lower than their preset value. If not used, this pin should be left open circuit.

(1)

(2)

6

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