The MAX5940B evaluation board is a fully assembled and tested surface-mount circuit board that uses the MAX5940B, an 8-pin SO-packaged network PD interface controller that conforms to the IEEE 802.3af standard. It is suitable for PDs in LAN power supply systems that require DC power through Ethernet ports, such as IP phones, wireless access points, and security cameras. The evaluation board demonstrates all the features of the MAX5940B, including PD detection, configurable PD classification, programmable surge current, and undervoltage lockout (UVLO). It also includes a 275kHz, isolated, 6W, flyback DC-DC converter with a MAX5014 current-mode PWM controller, powered by the -48V voltage output of the MAX5940B.
The MAX5940B Evaluation Board is a fully assembled, tested evaluation kit that provides a PD interface controller compliant with IEEE 802.3af. It includes an isolated 6 W, 4.25 V DC‑DC converter, Ethernet RJ‑45 connector, and test points for voltage and signal monitoring.
The manual covers hardware setup, jumper configuration for PD classification, UVLO programming, external DC‑DC converter interfacing, and safety precautions for high‑voltage operation. Component lists, schematics, and layout diagrams are provided for reference. This manual is written in Chinese.
| Input voltage range | -36 V to -60 V |
|---|---|
| Output voltage | 4.25 V |
| Maximum output current | 1.4 A |
| Conversion efficiency | up to 82.2 % |
| Isolation voltage | 1500 V |
| Switching frequency | 275 kHz |
| Power rating of on‑board converter | 6 W |
| UVLO (under‑voltage lockout) | Programmable |
| Surge current limit | Adjustable |
The board provides a regulated 4.25 V output capable of delivering up to 1.4 A.
UVLO is programmed by installing resistors R1 and R2 whose combined value must be 25.5 kΩ; the voltage division sets the start‑up and UVLO thresholds.
The board operates with an input voltage between –36 V and –60 V.