Up to 5 W solar battery charger with embedded
Features
■ High-efficiency monolithic step-up DC-DC
converter
■ Proprietary “perturb & observe” embedded
MPPT algorithm
■ Very low input voltage (down to 0.3 V)
■ Integrated N-channel and P-channel
MOSFETs with low R
■ Overcurrent and overtemperature protection
■ Input reverse polarity protection
■ LED charge status indicator
■ RoHS compliant
resistance
ON
STEVAL-ISV006V2
MPPT based on the SPV1040
Data brief
STEVAL-ISV006V2
Description
The STEVAL-ISV006V2 demonstration board is
based on the SPV1040 high efficiency solar
battery charger with embedded MPPT. The
SPV1040 device is a low power, low voltage,
monolithic step-up converter with an input voltage
range from 0.3 V to 5.5 V, and is capable of
maximizing the energy generated by even a single
solar cell (or fuel cell), where low input voltage
handling capability is extremely important.
Thanks to the embedded MPPT algorithm, even
under varying environmental conditions (such as
irradiation, dirt, temperature) the SPV1040 offers
maximum efficiency in terms of power harvested
from the cells and transferred to the output.
The device employs an input voltage regulation
loop, which fixes the charging battery voltage via
a resistor divider. The maximum output current is
set with a current sense resistor according to
charging current requirements.
The SPV1040 protects itself and other application
devices by stopping the PWM switching if either
the maximum current threshold (up to 2 A) is
reached or the maximum temperature limit (up to
155 °C) is exceeded.
The STEVAL-ISV006V2 demonstration board is
supplied by a PV panel with P
which can be replaced with PV panels with P
up to 5 W (V
< 5 V) depending on application
OC
of 200 mW,
PK
PK
requirements.
The output load is a 220 mF, 5.5 V supercapacitor that can be replaced with lead-acid,
NiCd or NiMh rechargeable batteries (max
voltage = 5 and > V
of the selected PV panel).
OC
The demonstration board provides a simple
charge status indicator using 2 LEDs, and 3
trimmers are available to allow setup according to
the specific application requirements.
October 2011 Doc ID 018650 Rev 3 1/4
For further information contact your local STMicroelectronics sales office.
www.st.com
4
Schematic diagram STEVAL-ISV006V2
1 Schematic diagram
Figure 1. STEVAL-ISV006V2 circuit schematic
PV+
PV-
optional
J
V
D
V
1
LOAD+
OUT
LOAD-
C
OUT
Lx
Lx
SHUT
XSHUT
R
5
R
3
C
IN
VR
GND
C
4
4
V
OUT
I
CTRL_PLUS
I
CTRL_MINUS
V
CTRL
C
R
F1
R
C
F2
F
2
R
S
R
1
VR
2
R
V
BAT+
Battery Charge
Control circuit
VR
10
R
9
V
J28
Super
Cap
BAT-
AM06706v1
2/4 Doc ID 018650 Rev 3