H32 is an attempt to create an energy efficient ESP32/RFM9x devkit which allows easy installation and testing while developing firmware but, once the project built around it is ready you can simply move to an enclosure or its installation location and have a working project without need to redesign a custom board for it.
H32 is built around an ESP32-WROOM-32U and has room for an optional RFM9x module.
Onboard you will find an RTC with its own battery & a humidity/temp sensor from sensirion so you can monitor the conditions inside the enclosure.
There are two main switches. First one selects power mode between OFF-TIMER & ON states. Set to ON your power efficiency depends on firmware and ESP32's deep sleep. Set to Timer, a nanopower timer (TPL5111) is power cycling the controller with the second switch selecting 30-60min or a custom interval (set by two easy to solder TH/1206 resistors). In timer mode only the LDO & Timer draw current from the power source and in theory would consume about 50nA combined (I think 3-4x that much is going to be more realistic accounting for leackage currents etc.
Programming H32 is pretty much standard procedure, there are onboard reset and flash buttons and uart access but i also designed a small CH340N USB/TTL adapter with autoreset to connect on the 6pin header. Removing the usb/ttl circuitry from the devkit means lower power consumption and lower cost as even if you need to install several units, you only need one adapter.
H32 has all available connections going through spring loaded terminals making it so much easier to wire sensors, inputs and outputs and you dont need to breadboard the devkit itself to make a functional project setup. You get access to UART, SPI, I2C, 4x GPIO & 4x Analog inputs. Voltage dividers on the analog inputs have a 10k resistor to ground and you can set the dividers by adding TH/1206 resistors.
There is an XT30 connector to connect to battery or power source and as is it will perform very well with possibly readily available or low cost and easy to source 12V solar panels/LA battery chargers/7Ah LA batteries. I am already working on 2 or 3 alternative power sources with matching PSU board connecting on top of H32.
PCB is 84x72mm and is designed to fit DEGSON PCB carriers or DRG-03 brackets to allow installation on DIN RAIL.
I am also working on a backplate to fit 100x100mm IP65 electrical enclosures with onboard battery charger battery holder and protections for single cell 18650 Li-Ion.
H32 is the official sensor node board for mudpi project
mudpi.app and will launch a campaign on groupgets.
We will make a limited number available as early birds, priced a bit lower than campaign or retail price and make H32 available to peple willing to test and use it while providing feedback and possibly willing to help promote it.