Single-chip power over Ethernet

National Semiconductor’s LM5070 is claimed to be the first single-chip Power Device (PD) interface port and pulse-width modulator (PWM) controller that meets the IEEE 802.3af standard.

The LM5070 integrates an 80V, 400mA line connection switch and associated Power over Ethernet (PoE) interface circuits with a dc-dc controller that steps down the 48V input to power various loads.

It also offers an integrated, high-frequency, current-mode dc-dc controller, user-programmable under-voltage threshold and hysteresis, and a highly accurate fault current control loop.

What is more, it features a maximum operating voltage of 75V, user-programmable oscillator frequency up to 1 MHz and over-temperature protection, plus a voltage reference and high-performance error amplifier for non-isolated applications.

The LM5070 device is available in small-footprint LLP-16 or TSSOP-16 packages. Lead-free package options are also available.

The product is priced at $1.75 each in 1,000-unit quantities.