We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Green circuit board HAT with 0.91 inch white OLED and cooling fan

WaveShare

WaveShare POE HAT (B) 0.91" OLED handheld pcs accessory

SKU CH-RB9W-BM85X

Power-over-Ethernet HAT with 0.91" OLED and cooling fan for Raspberry Pi 4B and 3B+, delivering 5 V 2.5 A from 37–57 V input and showing temperature, IP and fan status on a 128×32 SSD1306 display

  • CPU TypeOther
  • Powers Raspberry Pi via 802.3af PoE network with 37V to 57V DC input
  • Delivers 5V 2.5A DC output for stable single-cable operation
  • 91" OLED shows CPU temperature IP address and fan status at 128×32 pixels
  • Onboard cooling fan runs automatically or under programmable I2C control via PCF8574
  • Compact 56.5×65mm HAT fits Raspberry Pi 4B and 3B+ without extra bulk

Power-over-Ethernet HAT with OLED

This PoE HAT (B) supplies a Raspberry Pi 4B or 3B+ with 5 V at 2.5 A through an 802.3af-compliant network link. The board accepts 37 V to 57 V DC input and includes a 0.91 inch OLED driven by an SSD1306 controller at 128 by 32 pixels. A PCF8574 I/O expander adds spare pins and a dedicated fan-control line, while an onboard cooling fan can run automatically or under software control via a hardware switch.

Builders who need cable-free power for a Pi

The HAT suits projects that already have 802.3af power-sourcing equipment such as a PoE switch or injector; without that infrastructure the board cannot operate. It is not for users who lack PoE hardware, who need higher current than 2.5 A, or who require a different single-board computer form factor.

0.91 inch 128×32 OLED for live system data

The white OLED shows processor temperature, IP address and fan status in real time, letting operators monitor headless units at a glance. This display is the key feature that distinguishes the HAT from basic PoE add-ons.

Highlights

  • Powers Raspberry Pi via 802.3af PoE network with 37V to 57V DC input
  • Delivers 5V 2.5A DC output for stable single-cable operation
  • 91" OLED shows CPU temperature IP address and fan status at 128×32 pixels
  • Onboard cooling fan runs automatically or under programmable I2C control via PCF8574
  • Compact 56.5×65mm HAT fits Raspberry Pi 4B and 3B+ without extra bulk

Specifications

CPU TypeOther

Questions about this item

Does the POE HAT (B) include the 802.3af power-sourcing equipment or must that be bought separately?

The HAT itself is included; an 802.3af power-sourcing device such as a PoE switch or injector is required and sold separately.

Should I choose this HAT for a Raspberry Pi 4B or a 3B+?

The board is compatible with both Raspberry Pi 4B and 3B+, so either model works.

What does the 5 V 2.5 A output mean when the HAT is powered from a 37–57 V PoE line?

It delivers up to 5 V at 2.5 A to the Raspberry Pi, enough for the board and typical USB peripherals.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.