Librem 5 Phone – Chestnut¶
The sections on this page contain information about the Chestnut revision of the Librem 5 phone.
Phones in the Chestnut shipment have these improvements over those in the Birch shipment:
- The red LED always indicates the charging state, regardless of whether or not the PMIC is powered. (It can illuminate when the phone is “off”.)
- Fixed an issue where the TPS65982 was not entering its APP mode when VBUS was presented before the PMIC’s BUCK6 VDD_3V3 rail. This means that rapid charging occurs regardless of whether the TPS65982 is first powered via USB or via the battery – rapid charging always works.
- The microSD card is now read-write.
- The USB 2.0 D+/D- is now routed directly to the USB-C receptacle so it does not rely on the TPS65982 entering its APP mode to use the data interface. This prevents an extremely unlikely but potential brick situation, which could only really be achieved on a Birch unit if done deliberately.
- Improved the WWAN kill switch inrush current such that using a PLS8 M.2 module would not cause the device to reset if you flip the switch off and back on.
The version of the Quick Start Guide included with the phone can be downloaded:
- Wolfson Media WM8962
- Headphones and external microphone via CTIA-configured 3.5mm jack
- Bluetooth I2S interface
- Bluetooth (SDIO)
- RedPine WiFi/BT M.2 module on SDIO
- Broadmobi BM818-E1 or BM818-A1 WWAN module
- Diodes Incorporated Power Switch [datasheet]
- WWAN (Modem)
- Microphone and Camera
The 15 test points for UART1, UART2, JTAG, and the BOOT_MODE0/1 pins can be found below the WLAN module on the rear of the phone, as shown with the rear cover removed.
The USB test points are located in the recessed area above the battery compartment.