SPECIFICATIONS

Brand Name: RCmall

High-concerned chemical: none

Model: LoRa32u4 II

Origin: Mainland China

Type: others

LoRa32u4 II Lora Development Board Module LiPo Atmega328 SX1276 HPD13 915MHz for Arduino IoT LoRaWAN

Description:
LoRa32u4 II is a light and low consumption board based on the Atmega32u4 and HPD13 915MHz LoRA module and an USB battery charging circuit. Ideal for creating long range wireless networks that can exceed 2.4 GHz 802.15.4 and similar, it is more flexible than Bluetooth LE, does not require high power unlike WiFi and offers long range.

The ATmega32u4 is clocked at 8 MHz and 3.3 V. This chip has 32 K of flash, 2 K of RAM and built-in USB to Serial communication, debugging and programming capabilities without the need for an external FTDI chip, it can also act as an HID device (mouse, keyboard, USB MIDI device, etc).
This board is also equipped with a LiPo and Liion charging circuit and a standard battery interface. It is fully compatible with Arduino. A white user led is tied to pin 13. An orange LED is used for charging status.

HPD13 wireless module, using high-performance, highly integrated RF transceiver chip SX1276 design. Advanced LoRaTM spread spectrum communication technology to ensure that the module communication distance and anti-jamming capability greatly improved, and also achieved a very low current consumption. In the LoRaTM mode, the HPD13 provides higher reception sensitivity performance, more robust anti-jamming capability, and improved communication distance and reliability compared to the same transmit and receive modules on the market. In normal (G) FSK mode, it also provides industry-specific receiver sensitivity, as well as very high communication rates.

ATmega32u4 @ 8MHz with 3.3V logic/power
3.3V regulator with 500mA peak current output
USB native support, comes with USB bootloader and serial port debugging
Built in 100mA lipoly charger with charging status indicator LED
Reset button

HPD13:
Receive current: 10 ~ 14mA
Interface Type: SPI
Operating temperature: -40 ° C to + 85 ° C
Digital RSSI function
Automatic frequency correction
Automatic gain control
Radio wake-up function
Low voltage detection and temperature sensor
Fast wakeup with frequency hopping
Highly configurable packet handlers

LoRa32u4II revision 1.3 improvements :

1. LOW POWER
1.1. The battery monitoring circuit is now active and enabled by the previously unused pin PB0 (not broken-out on headers), it must be enabled (high) to allow battery monitoring.
1.2. The battery charger is now controlled, it must be enabled (high) by PB0 to allow battery charging.
1.3. The LDO has been replaced for an ultra low IQ LDO (0.5uA).
1.4. Overall sleep current has been lowered from 260.2uA to 183.8uA (tested with Atmega32u4 in watchdog sleep mode @ 8MHz and LoRa circuit in sleep mode).

2. USAGE
2.1. LoRa DIO1 is now connected by default to Atmega32u4 pin 5 (PC6) allowing direct use of LMIC and other LoRaWAN libraries without soldering, it is still possible to disable this link by opening the DIO1 solder jumper on topside.
2.2. LoRa DIO2 and DIO3 are now routing to Atmega32u4 pin 6 (PD7) and 14 (PD5), solder jumpers are open by default (these DIO pins are rarely used).
2.3. Atmega32u4 pins 0 (PD2),1 (PD3) for UART and 2 (PD1), 3 (PD0) for I2C are now free for use.
2.4. LoRa DIO pins solder jumpers have been moved on topside for better accessibility.
2.5. Pull-up resistors (4.7K) have been added on the I2C bus.
2.6. The antenna uFL connector has been moved on topside to ease access.