Freescale Creates Integrated Power Supply Solution for PoE Devices

By offering significant cost savings and flexibility advantages over traditional AC power, Power over Ethernet (PoE) technology continues to gain market momentum. To meet this growing demand, Freescale Semiconductor (NYSE:FSL) (NYSE:FSL.B) has introduced the MCZ34670, a single-chip PoE controller.

The MCZ34670 combines a powered device (PD) interface port supporting the IEEE 802.3af PoE standard and a pulse width modulator (PWM) controller. This high level of integration enables developers to design cost-effective Ethernet-powered end devices with minimal external components and exceptional design flexibility.

“While the use of Power over Ethernet has traditionally been associated with wireless LAN and voice over IP (VoIP) applications, the powered device market continues to gain ground in applications such as RFID tags and network security cameras as IT managers realize the cost savings, flexibility and reliability of PoE,” said Marianne D’Aquila, founder and principal analyst of Information Resources. “Freescale’s MCZ34670 controller provides an integrated, programmable solution to meet the needs of existing and future PoE-powered devices.”

The MCZ34670 contains the essential features needed to support the IEEE 802.3af standard and provides comprehensive signature detection and power classification functions for PoE applications. The MCZ34670 also incorporates thermal protection circuitry to help protect powered devices in case of high power dissipation.

Featuring an integrated high-performance switching regulator, the MCZ34670 provides excellent line and load regulation and drives an external power MOSFET with a sense resistor. The switching frequency is adjustable between 100kHz and 400 kHz with a 50 percent duty-cycle limit. This flexibility is advantageous for applications not designed to exceed an on-time of 50 percent of a given switching frequency and period.

“The demand for VoIP and wireless access points is creating a significantly larger market opportunity for PoE-capable products,” said Arman Naghavi, vice president and general manager of Freescale’s Analog, Mixed-Signal & Power Division. “Freescale’s integrated PoE controller is designed to enable new types of Ethernet end devices to connect to the Ethernet network and receive power safely, efficiently and cost effectively.”

Benefits of PoE Technology
PoE provides a versatile, cost-effective alternative to AC power for a wide variety of network devices, such as wireless access points, IP phones, IP cameras, laptop computers, networked kiosk terminals, security video cameras, emergency lighting systems, building controls, MP3 players and PDA chargers. These devices traditionally have required both types of connections – AC power and Ethernet.

PoE equipment benefits end users of networked peripheral devices by enabling those devices to receive power over standard category 5 LAN cabling safely, without the need for separate AC adapters or additional power lines. PoE reduces or eliminates installation costs, saves space and makes it easier to relocate appliances within the workplace. In addition, PoE-connected appliances can be managed, shut down or reset remotely in an efficient, centralized manner.

MCZ34670: Fully Integrated PoE Solution

PD interface

  • Integrated IEEE 802.3af compliant interface
  • Signature detection and classification functionality
  • Integrated isolation switch
  • Programmable inrush current control
  • Adjustable under voltage lockout
  • Input voltage range up to 80 V

PWM controller

  • Current mode control
  • Adjustable oscillator – 100 kHz to 400 kHz (default 250 kHz)
  • Leading-edge blanking
  • Input over voltage protection
  • Extensive protection circuitry
  • Open-drain reset output capability
  • Internal slope compensation circuitry
  • 50 percent duty cycle limitation

Pricing and Availability
The MCZ34670 is available in production quantities at a suggested resale price of $2.08 (USD) in 10,000-piece quantities. Suggested product pricing is less than $2 in high volume. The MCZ34670 evaluation boards are available now for a suggested resale price of $115 (USD). The KIT34670EGEVBE development tool incorporates an IEEE 802.3af compliant powered device interface with a 5 V isolated output voltage and adjustable UVLO, as well as inrush current. This board is University of New Hampshire InterOperability Laboratory (UNH-IOL) tested and compliant. The M52235EVB ColdFire(R) architecture evaluation board with a PoE port using the MCZ34670 powered device is available for the suggested resale price of $299 (USD).

About Freescale Semiconductor
Freescale Semiconductor, Inc. (NYSE:FSL) (NYSE:FSL.B) is a global leader in the design and manufacture of embedded semiconductors for the automotive, consumer, industrial, networking and wireless markets. Freescale became a publicly traded company in July 2004. The company is based in Austin, Texas, and has design, research and development, manufacturing or sales operations in more than 30 countries. Freescale, a member of the S&P 500(R), is one of the world’s largest semiconductor companies with 2005 sales of $5.8 billion (USD).

Freescale(TM) and the Freescale logo are trademarks of Freescale Semiconductor, Inc.