and then CC-CV charging. Initial charging for
depleted batteries is a max of 100mA.
Monitoring:
Monitor Input V, Output V, Battery V and
board (battery) temperature using an on-board
ADC. Sample Python Code provides capabilities to
monitor ADC and shutdown the Pi when the battery
V is low.
ADC capabilities:
A 12-bit, delta-
sigma (ΔΣ) analog
-to-
digital converter (ADC). Three I
2
C addresses are
available, jumper selectable. Minimum sensitivity is
3mV. Sensitivity can be improved by changing
Python code.
ADC used:
TI TLA2024IRUGR
ADC Addresses:
0x49 (default), 0x48, 0x4B
Battery Full Charge Voltage:
Li-Ion, Li-Polymer 4.2 V;
Li-FePO4 3.2 V
Spacers
M2.5x20mm spacers recommended. Spacers are
recommended for mechanical stability and to clear
USB and Ethernet connectors and provide ambient
cooling air space. Four spacers are needed.
Connection Points
Connection points
are spaced 2.54mm (100 mils)
apart. Jumpers, terminal-blocks or JST connectors
can be used for connections. Connections are
marked on the board top layer as well as on the
bottom layer.
Terminal Blocks recommended/used:
Two Position
Wire-to-Board Terminal Block, Horizontal with
Board, 2.54mm (0.1inch) pitch, green color (color
may vary), Thermoplastic, -30°C ~ 105°C, 6A, 125V.
20-30AWG wire can be used. Steel Zinc Screws,
max torque 0.15 Nm (1.3 lb-in).
Brass contact and
clam material. RoHS 2 compliant. Recommend
Onshore Technology Inc OSTVN02A150 Terminal
blocks. Other manufacturers also provide
equivalent terminal blocks, which can also be used
Terminal Blocks 3.3V UPS:
Soldered. 3.5mm spacing.
Power on/off Switch
Reset:
Turn power off by pulling out Power On/Off
jumper shunt. Turn power back on by inserting
jumper shunt. Power shunt remove-reinsert
sequence causes a power reset and a reboot.
External Switch:
Instead of a shunt, an external
on/off switch can be connected to the jumpers. The
jumpers are 2.54mm
–
any 2.54mm connector can
be used. Please make sure the switch can sustain a
minimum of 5V, 3A.
On/Off Switch cable:
Available at several web sites.
An
example
is
via
Amazon,
product-id
B07FXXDN2M.
Dimensions
Board dimensions:
83mm x 35mm x 70mm (3.3” x
2.2” x 1.4”)
.
Weight:
About 50g (1.7 oz.) without batteries. Note
each 18650 battery adds approximately 50 grams
of weight.
Header:
Female pins on bottom. Male pins on the top.
Pin thickness appx. 0.6mm. Female pin height appx
16 mm. Male pin height appx 7 mm.
Warranty
90-day limited warranty. Warranty voided by
improper use.
Other Information
Battery Charging Temperature:
-10
o
C to +50
o
C,
outside this range, battery charging is disabled.
Electronics, battery holder:
-40
o
C to 85
o
C
Operating Humidity:
10% to 80% non-condensing.
Recommended peripherals
www.alchemy-power.com/products
for
other recommended products.
RoHS Compliance:
Electronic components, board
etc. are RoHS compliant.
Other:
CE Compliance certificate available on
request.
Code download:
