SPECIFICATIONS

DIYmall LoRa32u4 II Development Board SX1276 HPD13 915MHz Low-Power Lora Module for Arduino IoT

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

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 Blue-tooth 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.
Document Link : https://drive.google.com/file/d/0B8DSGdAr8_31RlFGV0JZNFU0V3c/view

Package includes:
Type 1
5 X LoRa32U4 II Lora Module Development Board
5 X 868MHz 915MHz GSM 1.13 Antenna
5 X JST-PH2.0MM-2P Cable

Or

Type 2
5 X LoRa32U4 II Lora Module Development Board
5 X 2DBi to SMA Antenna 868MHz 915MHz
5 X JST-PH2.0MM-2P Cable

FAQ

Q:Can this device run a software lorawan stack by itself or would it need another microcontroller?
A:Yes, it can
Q:It can be charged by 18650 battery?
A:Yes, it can. The charger will work with both LiPo and LiIon
Q:Is there a link for the board manager for arduino ide ? what is this board similar to?
A:Yes, document link is https://tinyurl.com/lora32u4-lora32u4ii, it is similar to Ada---fruit feather
Q:What is the transmission range of this ?
A:In LOS (line of sight) at SF8 and 17dBm the transmission range of LoRa32u4II is over 7.2km, at 20dBm it is even more
Q:The same code flashed to other boards (older revision and same revision) was working fine. I was at a LoRa/TTN meetup, so several boards were there brought by other visitors of the Meetup.The thing is, since it was not working, I did retry to reapply solder on the wire needed between DIO1 and D6 (needed for LMIC library for TTN network) and during this, the pad came off the PCB.So later I soldered the wire like shown on the picture and it still does not send data to the LoRa gateway.
A:The solder jumper of DIO1 goes to D1, not D6, so, if you use D6 you have to ensure the LMIC library has been set up to use D6 for DIO1 and not D1, otherwise it wont work.
Q:Can I get a Lora32u4 II V1.3 schematic?
A:Sorry about it, we do not provide the schematic. Pinout diagram is http://s5.ecpperp.com/flyfun/data/upload/product_img/191112/LORA32U4II-pinout.jpg If you have any problem when using it, please let me know, we will solve it for you
Q: Can I connect this development board to a Raspberry Pi Pico?
A: Yes, it can. Both are 3.3V logic level
Q: What's the maximum frequency value in its band interval, please? Does it reach up to 928MHz?
A: Yes, it can reach 928MHz, bu not advised to go over 915MHz. Otherwise the matching will not be ideal