hv110 Supertex, Inc., hv110 Datasheet - Page 3

• Manufacturer Part Number: hv110
• Description: Power-over-ethernet Interface Pd Controller Meets Ieee802.3af Tm Standard
• Manufacturer: Supertex, Inc.

Powered Ethernet Requirements
UVLO
Power-over-LAN
Ethernet or Powered VoIP) is the general concept of
providing high voltage (48VDC) power over existing
networking cables, such as Ethernet cables. This is
accomplished either by using the CAT5 Ethernet
Cable’s unused spare pairs or the signal pairs (ENV
B vs. ENV A).
In Power-over-LAN applications there are two main
types of equipment: the Power Sourcing Equipment
(PSE) and the Powered Device (PD). There is a third
type called Midspan equipment that plugs inline and
converts a conventional router into a PSE.
Power-over-Ethernet (PoE)
Standards
IEEE802.3af standard, DTE Power via MDI, deals
with the specification of the interface that can
supply/draw power using the same generic cabling
as that used for data transmission. It allows both
power and data to flow through the Media
Dependent Interface (MDI) (like 10Base-T, 100Base
TX or 1000BaseT) to the Data Terminal Equipment
(DTE
and electrical characteristics of two optional power
(non-data) entities – the Powered Device (PD) and
the Power Sourcing Equipment (PSE) that makes
this single interface possible. The mechanical and
electrical interface between PSE and PD and the
transmission line is achieved through the Power
Interface (PI) Devices (usually the LAN cables).
1
data and which controls the communication channel
Vpp
Vnn
(DTE) A device which acts as the source and/or destination of
1
) safely and effectively. It defines the functional
Figure 2. HV110 Functional Block Diagram
Regulator
UVLO
Timer
Restart
POR
Timer
(sometimes
Control
Logic
called
Temperature
Sensor
Powered
HV110
PWRGD
DRAIN
3
The
requirements, features and characteristics of the
PSE and PD devices for use in PoE applications.
HV110 is a PD controller IC, capable of handling all
the
IEEE802.3af standard.
A PD designed to this standard and within its range
of available power, can obtain both power and data
for operation via the standard LAN cables and there-
fore will not require any additional power sources or
connections.
PSE is defined as a device that provides a single
portion of the link (10BASE-T, 100BASE_TX or
1000BASE_T) with both the data it requires and the
power to process this data. PSEs may be placed
with the DTE/Repeater/Midspan. A PSE that is
located along with the DTE/Repeater is called
Endpoint PSE, while a PSE that is located within the
link, between the MDIs is called a Midspan PSE. All
the specifications for the PSE sitting in the End Point
(e.g. the router) may not apply for the Midspan PSE.
Even though HV110 is a PD device, it is closely
associated with the operation of PSE, in fact it is
dependent on the PSE for its normal operation.
HV110, however, unlike many other PD controllers,
provides redundant PSE protections and timings for
maximum protection while ensuring compliance.
Hence certain basic functionalities of the PSE are
included in this data sheet for better understanding
some of the features and operation of PDs.
current
V
V
DRAIN – Internal N-channel MOSFET drain output
UV/ENABLE – Under Voltage Lockout Input
PWRGD – Active-Low Power Good Output
IEEE802.3af
PP
NN
– Positive voltage supply input
– Negative voltage power supply input
Figure 3. Package Drawing: DPAK-5
and
Pin Description
timing
standard
requirements
specifies
HV110
of
A061104
the
the