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Ordering Information

Code

Description

AH

Horiz. T/H

(EUP)

AS

(EUQ)

Code

Voltage

A5 V

B

3.3 V

C

12 V

Notes:

(1) Reference the applicable package reference drawing for the dimensions and PC board layout

(2) “Standard” option specifies 63/37, Sn/Pb pin solder material.

Pin Descriptions

This is the negative output from the module, with

respect to +Vout. Both the +Vout and –Vout terminals are

isolated from the Ethernet input, and used to power the

PD appliance. When this pin is connected to the PD appli-

ance common, a positive supply voltage is produced at

+Vout.

By connecting a single resistor to this pin, the

regulated output voltage may be adjusted/trimmed by up

to ±10 % from the original set-point value. If no adjust-

ment is desired, this pin should be left open circuit.

This is the positive output from the module with

respect to –Vout, and is used to power the PD appliance.

By connecting this pin to the PD appliance common, a

negative supply voltage will be produced at –Vout.

Input Ref:

This pin provides access to the –Vin of the

internal DC/DC converter, and is the 0-VDC reference

for the ‘Output Inhibit’ control.

Detect A:

This is a control input that is normally left open

circuit. The module incorporates an internal 24.9-k

Ω

resistor, between the ‘Detect A’ and ‘Detect B’ pins. This

provides the PD with a correct “valid device” detection

resistance for the PSE. By placing an external resistor

between the ‘Detect A’ and ‘Detect B’ pins (in parallel with

the internal 24.9-k

Ω resistor) the module can be made to

identify itself as a “non-valid device.”

Detect B:

This pin is used in conjunction with the ‘Detect A’

input only when it is desired for the PD to communicate

a “non-valid” device signature to the PSE (see ‘Detect A’

description). ‘Detect B’ is also the rectified DC output from

the module’s internal diode bridges, and represents the

positive DC input to the module’s DC/DC converter.

Connecting an external capacitor between this pin and the

‘Input Ref’ pin (0 V), adds more filter capacitance across

the input of the DC/DC converter.

Data Line A/B:

These are the main inputs from which

the module obtains DC input power from the Ethernet

connector. The connection of these inputs to the Ethernet

connections must be via an IEEE 802.3af compliant signal

tranformer, that is designed for use in a PoE application.

This is necessary to preserve the integrity of the Ethernet

data traffic. Consult the example application for further

information.

Spare Line A/B:

These are alternative inputs from which

the module may obtain DC input power. In a PoE appli-

cation, ‘Spare Line A’ may be directly connected to pins 4

& 5, and ‘Spare Line B’ to pins 7 & 8 of an Ethernet RJ-45

connector. These connections are not used for data trans-

mission.

Class A/B:

The control inputs ‘Class A’ and ‘Class B’ allow

the PD Class to be programmed from the module. The

module incorporates an internal 4.42-k

Ω resistor between

the ‘Class A’ and ‘Class B’ inputs. This corresponds

to a default “Class 0” PD classification signature being

sent to the PSE. By adding an external resistor across

these pins, the module can be programmed to other PD

classifications. For further information, consult the PD

class reference table in the application notes.

Output Inhibit:

This is an open-collector (or open-drain)

negative logic input. Applying a low-level voltage to this

input, with respect to the ‘Input Ref ’ pin, turns off the

DC output voltage from the module. If the pin is left

open-circuit, the module will operate as normal, pro-

ducing an output voltage whenever it is connected to a

valid PoE input source.

PTB48540 Series

10-W Power-Over-Ethernet Isolated

Power Module Assembly

SLTS224B – APRIL 2004 – REVISED JULY 2004

Not Recommended for New Designs