Overview
The NCP1081DEG, produced by ON Semiconductor, is a highly integrated Power over Ethernet (PoE) Powered Device (PD) interface and DC-DC converter controller. This component is designed to support both the IEEE802.3af and IEEE802.3at standards, enabling it to deliver up to 25.5 W for IEEE802.3at and up to 40 W for proprietary high power PoE applications. The NCP1081DEG combines an enhanced PoE-PD interface with a flexible and configurable DC-DC converter controller, making it an ideal solution for demanding medium and high power Ethernet applications.
This device eliminates the need for local power adaptors or power supplies, significantly reducing installation and maintenance costs. It is fabricated in a robust high voltage process and integrates a rugged vertical N-channel DMOS with low loss current sense techniques, suitable for harsh environments such as hot swap and cable ESD events.
Key Specifications
| Parameter | Min. | Typ. | Max. | Units | Conditions |
|---|---|---|---|---|---|
| VPORTP (Input power supply) | -0.3 | 72 | V | Voltage with respect to VPORTN1,2 | |
| VDDH (Internal regulator output) | -0.3 | 17 | V | Voltage with respect to ARTN | |
| VDDL (Internal regulator output) | -0.3 | 3.6 | V | Voltage with respect to ARTN | |
| CLASS (Analog output) | -0.3 | 3.6 | V | Voltage with respect to VPORTN1,2 | |
| INRUSH (Analog output) | -0.3 | 3.6 | V | Voltage with respect to VPORTN1,2 | |
| ILIM1 (Analog output) | -0.3 | 3.6 | V | Voltage with respect to VPORTN1,2 | |
| UVLO (Analog input) | -0.3 | 3.6 | V | ||
| Operating Temperature Range | -40 | 85 | °C | ||
| Junction Temperature | 150 | °C |
Key Features
- Supports IEEE802.3af and IEEE802.3at standards
- High power delivery up to 40 W for proprietary applications
- Programmable classification current and inrush current limit
- Adjustable under-voltage lockout (UVLO)
- Over-temperature protection
- Industrial temperature range: -40°C to 85°C
- Vertical N-channel DMOS pass-switch with low loss current sense technique
- Current mode DC-DC controller supporting isolated and non-isolated topologies
- Programmable switching frequency and soft-start time
- Pb-Free devices
Applications
- Industrial Ethernet devices
- PTZ and Dome IP cameras
- RFID readers
- MIMO WLAN access points
- High-end VoIP phones
- Notebooks and other high power Ethernet devices
Q & A
- What standards does the NCP1081 support?
The NCP1081 supports both the IEEE802.3af and IEEE802.3at standards.
- What is the maximum power delivery of the NCP1081?
The NCP1081 can deliver up to 25.5 W for IEEE802.3at and up to 40 W for proprietary high power PoE applications.
- What types of DC-DC converter topologies does the NCP1081 support?
The NCP1081 supports isolated and non-isolated fly-back, forward, and buck converter topologies.
- What is the operating temperature range of the NCP1081?
The operating temperature range is -40°C to 85°C with full operation up to 150°C junction temperature.
- Does the NCP1081 have over-temperature protection?
- How is the classification process handled by the NCP1081?
The NCP1081 supports Single Event Layer 1 classification, Dual Event Layer 1 classification, and Layer 2 classification (Data Link Layer classification) as per the IEEE802.3af and IEEE802.3at standards.
- What is the purpose of the nCLASS_AT pin?
The nCLASS_AT pin notifies the microprocessor of the powered device if a two-event hardware classification has occurred.
- Is the NCP1081 Pb-Free?
- What are some common applications of the NCP1081?
- How does the NCP1081 handle inrush current?
The NCP1081 has a programmable inrush current limit to manage the initial power-on surge.
