Freescale Delivers Integrated Power Supply Solution for PoE Devices
Freescale Semiconductor Inc. has introduced the MCZ34670 – a single-chip Power-over-Ethernet (PoE) controller that 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.
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 100 and 400kHz with a 50% duty-cycle limit. This flexibility is advantageous for applications not designed to exceed an on-time of 50% 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."
The MCZ34670 is available in production quantities at a suggested resale price of $2.08 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. The KIT34670EGEVBE development tool incorporates an IEEE 802.3af compliant powered device interface with a 5V 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® architecture evaluation board with a PoE port using the MCZ34670 powered device is available for the suggested resale price of $299.
