The LM5070 power interface port and PWM controller provides a complete integrated solution for Powered Devices (PD) that connect into Power over Ethernet (PoE) systems. The LM5070 integrates an 80V, 400mA line connection switch and associated control for a fully IEEE 802.3af compliant interface with a full featured current mode pulse width modulator dc-dc converter. All power sequencing requirements between the controller interface and switch mode power supply (SMPS) are integrated into the IC. Two options are available providing either an 80% maximum duty cycle limit with slope compensation (on the –80 suffix) device or a 50% maximum duty cycle limit and no slope compensation on the (–50 suffix) device.
The LM5070 is a fully IEEE 802.3af‑compliant power interface and pulse‑width‑modulation controller for Powered Devices in Power over Ethernet (PoE) systems. It integrates an 80 V, 400 mA internal MOSFET switch, programmable inrush current limit, classification current, and under‑voltage lockout, providing a complete solution for PoE power sequencing.
Key features include selectable maximum duty‑cycle limits (80 % with slope compensation or 50 % without), an 800 mA peak gate‑driver, and support for both isolated and non‑isolated applications. The device is offered in TSSOP‑16 and LLP‑16 packages, with detailed electrical characteristics and thermal specifications provided for designers.
| Maximum duty cycle (‑80 device) | 80 % |
|---|---|
| Maximum duty cycle (‑50 device) | 50 % |
| Peak gate driver current | 800 mA |
| Operating temperature range | -40 °C to +125 °C |
The LM5070‑80 device supports a maximum duty cycle of 80 % with slope compensation.
The LM5070 provides an 800 mA peak gate‑driver current.