DP83959 datasheet(7/38 Pages) NSC

7 / 38 page

4.0

Pin Descriptions (Continued)

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4.3

STATUS LED INTERFACE

All the DP83959's direct drive LED outputs can drive up to

14mA maximum. The LED outputs are intended to drive an

external LED with a series current limiting resistor. The Par-

tition/Link OK LED outputs can sink or source current and

are thus suitable for driving single or bi-color LEDs directly.

Bi-color LEDs can be connected between the A and B out-

puts (with series current limiting resistors) (see section

5.11).

The direct drive LED outputs are asserted during pow-

er-on/reset (either internal or external reset) and remain as-

serted for 1 second (nominal) following the trailing edge of

the internal/external reset signal. During the LED test at

power-on/reset, the Partition/Link OK 'A' outputs will all be

logic '1' and the 'B' outputs logic '0'.

DP83955/6 compatible LED drive outputs are only asserted

for the duration of the 1 second LED test following the trail-

ing edge of the internal/external reset (they are not asserted

during reset). The DP83955/6 compatible status LED

scheme

described

the

functional

description

(Section 5.13) as it requires external circuitry to latch the

status and drive the LEDs.

Signal Name

Type

Pin #

Description

P/L_1A

P/L_1B

O (14mA

max.)

Partition/Link OK LED 1 - A and B: LED outputs (for use with single or

bi-color LEDs) with the following function:

Link Status

/OK

Partition Status

/PART

PART

/PART

PART

A Output

B Output

P/L_2A

P/L_2B

O (14mA

max.)

Partition/Link OK LED 2 - A and B: LED outputs (for use with single or

bi-color LEDs) with the following function:

Link Status

/OK

Partition Status

/PART

PART

/PART

PART

A Output

B Output

P/L_3A

P/L_3B

O (14mA

max.)

Partition/Link OK LED 3 - A and B: LED outputs (for use with single or

bi-color LEDs) with the following function:

Link Status

/OK

Partition Status

/PART

PART

/PART

PART

A Output

B Output

P/L_4A

P/L_4B

O (14mA

max.)

Partition/Link OK LED 4 - A and B: LED outputs (for use with single or

bi-color LEDs) with the following function:

Link Status

/OK

Partition Status

/PART

PART

/PART

PART

A Output

B Output

P/L_5A

P/L_5B

O (14mA

max.)

Partition/Link OK LED 5 - A and B: LED outputs (for use with single or

bi-color LEDs) with the following function:

Link Status

/OK

Partition Status

/PART

PART

/PART

PART

A Output

B Output

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