圖片來源：MxL7704 PMIC Powers the Raspberry Pi 4 樹莓派目前使用中的供電系統是在 3B+ 開始改用的。供電系統的好壞對樹莓派來說是非常重要，一個運作良好的供電系統可以確保整塊板子的各功能運作正常，一旦供電出問題時，可能對板子所有功能造成各種問題，例如 USB、WiFi 功能失效或不正常，最嚴重的慘況就是讓整塊板子完全停擺變成一塊磚頭。 《供電系統之演進》 樹莓派供電系統的演進可以分成三個階段： 《第一階段是 Pi2 以前的供電》 重點提示：這代整體的供電源頭是來自於 Micro USB 5V，再轉換成 3.3V、2.5V、1.8V等部份供給系統上元件使用。 圖片來源：Introducing the Raspberry Pi Model B+ 接著來看看電路圖了解電源是怎開始的。電源從左側MICRO USB TYPE B這接頭端開始，經過 F3 保險絲再來到 D17 TVS（Transient voltage suppressor）及後端的濾波電容。 這樣的電路設計有什麼優點： 電路設計簡單，價錢便宜。 … Continue reading →
The Raspberry Pi PoE HAT powers a Raspberry Pi 3 Model B+ via an Ethernet cable. Power-sourcing equipment is required on the Ethernet network.
《特色》
The Raspberry Pi Power over Ethernet HAT is a small accessory for the Raspberry Pi computer. It can only be used with the Raspberry Pi 3 Model B+ (launched March 2018). The PoE HAT allows you to power your Raspberry Pi using Power over Ethernet–enabled networks; for this product to be used, the network it is connected to needs to have power-sourcing equipment installed.
Power-sourcing equipment for a 802.3af Power over Ethernet network
Connecting your PoE HAT to the Raspberry Pi
Before installing the PoE HAT, you must attach the supplied spacers in the four corners of the board
Then connect the Raspberry Pi PoE HAT to the two 0.1” headers (40 + 4) that are fitted on the Raspberry Pi
Once the PoE HAT board is connected, you can power the Raspberry Pi through its RJ45 network connector
Disconnecting your PoE HAT
Take care when separating the HAT from the Pi
Pull evenly so that it detaches from all the pins at the same rate; do not pull one end of the connector off before the other
Additional information
No modification to the main Raspberry Pi board is needed for this product to work. Please ensure that your Raspberry Pi’s software is up to date for all functionality to be available. The PoE HAT is fitted with a small fan that is controlled by the Raspberry Pi via I2C. The fan will turn on and off automatically depending on the temperature of the main processor on the Raspberry Pi.
《規格》
The Raspberry Pi PoE HAT is an add-on board for the Raspberry Pi 3 Model B+. It allows the Raspberry Pi to be powered via a power-enabled Ethernet network.
Shall only be powered using 802.3af-compliant power sourcing equipment; any external power supply used with the Raspberry Pi shall comply with relevant regulations and standards applicable in the country of intended use
Should be operated in a well-ventilated environment, and should not be covered
Should be placed on a stable, flat, non-conductive surface while in use, and should not be contacted by conductive items
Instructions for safe use
To avoid malfunction or damage to your Raspberry Pi product, please observe the following advice:
Do not block or obstruct the fan
Do not insert anything into the fan at any time
Do not expose the product to water or moisture, and do not place it on a conductive surface whilst it is in operation
Do not expose it to heat from any source; the product is designed for reliable operation at normal room temperatures
Take care whilst handling to avoid mechanical or electrical damage to the printed circuit board and connectors
Avoid handling the Raspberry Pi while it is connected to a power outlet; only handle by the edges to minimize the risk of electrostatic discharge damage
All other peripherals used with the Raspberry Pi should comply with relevant standards for the country of use and be marked accordingly to ensure that safety and performance requirements are met; these peripherals include, but are not limited to, keyboards, monitors, and mice used in conjunction with the Raspberry Pi
* 注意：本商品不包含 Raspberry Pi 3 Model B+。 $ 840 (單買 PoE HAT)
很多人拿到 Pi 3B+ 之後會迫不及待的把原本在 Pi 3B 上所使用的 SD 卡拿到 Pi 3B+ 使用，但是會發現無法開機。這是因為 Pi 3B+ 使用新的晶片(BCM2837B0)，因此如果沒有安裝 2018-03-13 以後所發布的核心(kernel)或是韌體(firmware)是無法直接使用的。
2018-03-13:
* Raspberry Pi 3 B+ support
* WiFi is disabled until wireless regulatory domain is set (Pi 3 B+ only)
- The domain can be done through 'Raspberry Pi Configuration' (rc_gui),
'raspi-config' or by setting 'country=' to an appropriate ISO 3166
alpha2 country code in /etc/wpa_supplicant/wpa_supplicant.conf.
$ sudo rfkill unblock wifi
$ sudo rfkill list
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
1: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
Pi 3B+ 這次新增了 MaxLinear MxL7704 電源管理 IC，可有更好的溫度管理策略。例如在 70°C 以下可以使用 1.4GHz 全速運轉；但超過了 70°C 就會降到 1.2GHz 的速度。可用 Sysbench 看溫度/頻率的曲線圖。
圖片來源：RASPBERRY PI 3 MODEL B+ ON SALE NOW AT $35
2018-03-13:
* Raspberry Pi 3 B+ support
* WiFi is disabled until wireless regulatory domain is set (Pi 3 B+ only)
- The domain can be done through 'Raspberry Pi Configuration' (rc_gui),
'raspi-config' or by setting 'country=' to an appropriate ISO 3166
alpha2 country code in /etc/wpa_supplicant/wpa_supplicant.conf.
* Default wireless regulatory domain is now unset
* Added support to desktop for different screen sizes and resolutions,
including multiple preset options in Appearance Settings and pixel doubling
option in Raspberry Pi Configuration
* Version 2.1.16 of Thonny included
* Version 29.0.0.113 of Adobe PepperFlash player included
* Version 1.2.post1 of Pygame Zero included
* Bluetooth plugin now supports connection to Bluetooth LE HID devices
* Network plugin now indicates 5G-compatible APs
* Latest changes to Bluez ALSA service merged
- service now started on CLI boot as well as GUI boot
* Latest changes to dhcpcd networking plugin merged
* Improved support for running on pi-top devices
* Small design changes to PiX theme and icons
* Bug fix - hide spurious window resize handles
* Bug fix - Scratch 2 remote GPIO state block now works correctly
* Updated WiFi Firmware
- brcmfmac43455-sdio 7.45.154
- brcmfmac43430-sdio 7.45.98.38
* New packages:
- policykit-1
- obconf
- python-buttonshim python3-buttonshim
- python-unicornhathd python3-unicornhathd
- python-pantilthat python3-pantilthat
* Linux kernel 4.9.80+
* Raspberry Pi firmware 3347884c7df574bbabeff6dca63caf686e629699
