ST公司的STEVAL-ISV006V2是采用SPV1040的5W太阳能电池充电器,是高效率的DC/DC转换器,嵌入了MPPT算法,输入电压可低至0.3V,输入反相极性保护.而SPV1040的输入电压从0.3V到本世纪5.5V,具有140 mΩ同步整流器和120 mΩ电源开关,固定的100kHz PWM频率,效率高达成95%,主要用在智能手机和GPS系统,小型电器和传感器,PMP,数码相机,玩具和手提保健设备.本文介绍了SPV1040主要特性,方框图,应用电路以及评估板STEVAL-ISV006V2主要特性,电路图,材料清单和PCB布局图.
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 1.8 A) is reached or the maximum temperature limit (up to 155 °C) is exceeded.
An additional built-in feature of the SPV1040 is the input source reverse polarity protection, which prevents damage in case of reverse connection of the solar panel at the input.

SPV1040主要特性:
■ 0.3 V to 5.5 V operating input voltage
■ 140 mΩ internal synchronous rectifier
■ 120 mΩ internal power active switch
■ 100 kHz fixed PWM frequency
■ Duty cycle controlled by MPPT algorithm
■ Output voltage regulation, overcurrent and overtemperature protection
■ Input source reverse polarity protection
■ Built-in soft-start
■ Up to 95% efficiency
■ 3 mm x 4.4 mm TSSOP8 package

SPV1040应用:
■ Smart phones and GPS systems
■ Wireless headsets
■ Small appliances, sensors
■ Portable media players
■ Digital still cameras
■ Toys and portable healthcare

图1.SPV1040方框图

图2.SPV1040简化应用电路

评估板STEVAL-ISV006V2
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 PPK of 200 mW, which can be replaced with PV panels with PPK up to 5 W (VOC < 5 V) depending on application 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 > VOC of the selected PV panel).
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.

评估板STEVAL-ISV006V2主要特性:
■ 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 RON resistance
■ Overcurrent and overtemperature protection
■ Input reverse polarity protection
■ LED charge status indicator
■ RoHS compliant

图3.基本的升压应用电路

图4.评估板STEVAL-ISV006V2外形图

图5.评估板STEVAL-ISV006V2电路图
评估板STEVAL-ISV006V2材料清单:


图6.评估板STEVAL-ISV006V2 PCB布局图(顶层)

图7.评估板STEVAL-ISV006V2 PCB布局图(底层)