The figures below show the energy harvester circuit performance in terms of MPPT accuracy and power
conversion efficiency in case of light source from a fluorescent tube lamp 6’500 K (irradiation levels from 250 to 5
k Lux) and from the solar light (from 0.06 to 1 W/m2) irradiation conditions.
Figure 13.
STEVAL-GPT001V1 cradle board battery energy harvesting: indoor irradiation
Figure 14.
STEVAL-GPT001V1 cradle board battery energy harvesting: outdoor irradiation
1.4.3.4
Recharge via micro-USB connector
The
STEVAL-GPT001V1
cradle board has an ESD protected micro-USB connector that can be plugged to a 5 V
supply source (e.g., a USB port) to activate a fast battery recharge controlled by the STBC08PMR(For details on
the device, refer to the related datasheet at www.st.com).
The ESD protection is featured by
USBLC6-2P6
, a monolithic application specific device dedicated to high speed
interfaces. The very low line capacitance ensures a high level of signal integrity without compromising sensitive
chip protection against the most stringently characterized ESD strikes.
The
STBC08PMR
is a constant current/constant voltage charger for single-cell Li-Ion batteries designed to work
within USB power specifications.
The charge voltage is fixed at 4.2 V (typical value) and current limitation can be programmed via a single resistor
connected between PROG pin and GND.
UM2260
UM2260
-
Rev 2
page 12/25
