PYXOS-FT Datasheet, PDF (2/7 Pages) List of Unclassifed Manufacturers – Pyxos™ FT Network Chip

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Figure 1.
Pyxos FT Transceiver Block Diagram
The Pyxos FT network chip embeds both
the protocol for a Pyxos platform and
the transceiver for communicating on
the Pyxos network. With the networking
protocol implemented inside the chip,
only application development is left
to the user. The chip is a small 5mm x
5mm sized one that fits into virtually
any sensor or actuator. The chip can be
connected directly to digital I/O without
a microcontroller, making for an ultra-
compact smart device. Alternately, the
chip’s serial peripheral interface (SPI) port
can be interfaced with a wide variety of
low-cost microcontrollers to accommodate
more complex I/O requirements.
Network Architecture and
Components
Pyxos FT network consists of up to 32
Pyxos Points embedded inside sensors
and actuators, and a Pyxos Pilot to
interface with the outside world. Points
(Figure 2) can either be Unhosted (without
a microcontroller; with only digital I/Os)
or Hosted (with a microcontroller). Pilots
(Figure 3) need a microcontroller and can
either be Stand-Alone (not connected
to any external network) or Networked
(connected to a higher-level external
network e.g., LonWorks to communicate
with the outside world).
High Speed Deterministic
Response Time
A Pyxos FT network operates at 312.5
kilobits per second using a deterministic
signaling method by which all 32 Points
in the system are scanned every 25
milliseconds (proportionally faster with
fewer Points in the system). This rate of
speed allows Pyxos FT networks to be
used for closed-loop controls in process
and industrial applications, as well as
sensing and control applications that
require fast response time.
Potential applications include:
• vehicular controls
• fault monitors
• propulsion controls
• HVAC systems
• lighting systems
• burner and boiler controls
• security and fire/life
• elevator cab and floor call
• safety devices
• controls
• office automation equipment
Advanced Noise Immunity
Four different network coupling options
are available to cover a wide variety of
application environments. For applications
within an enclosure, the differential
receiver in the Pyxos FT IC provides rail-
to-rail common mode range and may be
connected directly to the network with
no additional components. For network
applications where AC mains based
common mode noise may be tens of volts,
a simple 4 component coupling circuit
provides +/-40V 50/60Hz common mode
range (far better than typical RS-485
transceivers). For extremely harsh noise
environments a transformer coupled
option provides a common mode range
of 277VAC at 50/60Hz and >50Vpp
immunity to higher frequency common
mode noise - passing the highest level of
EN61000-4-6 conducted RF immunity.
Free Topology Wiring and
Link Power
The Pyxos FT network sends both power
and data on the same wire pair, a feature
known as “Link Power”. Link power
eliminates the need for an additional pair
of power wires and interface terminals,
further reducing the cost, size, and
complexity of Pyxos FT Points. Pyxos FT
networks support free topology wiring
architecture that allows network cabling
in star, loop, daisy chain or bus topology
or any combination of these. Free
topology wiring reduces the time and
expense of node installation by allowing
the wiring to be installed in the most
expeditious and cost-effective manner.
Seamless Integration with
Outside World
Control information gathered from Pyxos
FT Points is disseminated by a Pyxos FT
Pilot to programmable logic controllers
(PLCs), data gathering panels, host
processors, LonWorks control networks,
the Internet, and beyond. The published
API makes it easy to interface with the
Pyxos Pilot. The Pyxos API uses the
same data type definitions as those
developed for LonWorks networks,
making integration with LonWorks
networks seamless.
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