LCD Display Inverter

ST’s STEVAL-ISV006V2 is a 5W solar battery charger using SPV1040. It is a high-efficiency DC/DC converter with embedded MPPT algorithm. The input voltage can be as low as 0.3V and the input is reversed polarity protection. The SPV1040 has an input voltage ranging from 0.3V to 5.5V, a 140mΩ synchronous rectifier and a 120mΩ power switch, a fixed 100kHz PWM frequency, and an efficiency as high as 95%. Mainly used in smart phones and GPS systems, small appliances and sensors, PMP, digital cameras, toys and portable health care equipment.

The SPV1040 device is a low-power, low-voltage, monolithic boost converter. Its input voltage ranges from 0.3 V to 5.5 V. It can even produce energy from a single solar cell (or fuel cell) to a larger extent. This is very important for low input voltage processing capabilities. Thanks to the embedded MPPT algorithm, even under different environmental conditions (such as irradiation, dirt, temperature), SPV1040 can also provide the most efficient power (obtained from the battery) and transmit it to the output. The device uses an input voltage regulation loop to repair the voltage of the rechargeable battery through a resistor divider. According to the requirement of charging current, its maximum output current is set by a current detection resistor. If the maximum current threshold (1.8 A) or the maximum limit temperature (155°C) is reached, the SPV1040 can protect itself and other application equipment by turning off the PWM switch. The additional built-in function of SPV1040 is input source reverse polarity protection to prevent damage to the solar panel when the input terminal is connected reversely.

Figure 1 Block diagram of SPV1040

Figure 2 SPV1040 simplified application circuit

Main features of SPV1040

• 0.3 V~5.5 V input working voltage

•140mΩ internal synchronous rectification

• 120mΩ internal power active switch

• 100kHz fixed PWM frequency

• MPPT algorithm for duty cycle control

• Adjust output voltage, over current and over heat protection

• Reverse polarity protection of input source

• Built-in soft start

• Up to 95% efficiency

• 3mm×4.4mm TSSOP8 package

SPV1040 application

•Smartphone and GPS system

•Wireless Headphones

•Small appliances, sensors

•Portable media player

•Digital Camera

•Toys and portable medical equipment

STEVAL-ISV006V2 evaluation board

The STEVAL-ISV006V2 demo board is designed based on the SPV1040 high-efficiency solar battery charger and embedded MPPT. SPV1040 is a low-power, low-voltage, monolithic boost converter with an input voltage range of 0.3 V~5.5V. It can even produce energy from a single solar cell (or fuel cell) in large quantities, which is suitable for low input The voltage handling capacity is very important. Thanks to the embedded MPPT algorithm, even under different environmental conditions (such as irradiation, dirt, temperature), SPV1040 can also provide the most efficient power (obtained from the battery) and transmit it to the output. The device uses an input voltage regulation loop to repair the voltage of the rechargeable battery through a resistor divider. According to the requirement of charging current, its maximum output current is set by a current detection resistor. If the maximum current threshold (1.8A) or the maximum limit temperature (155°C) is reached, the SPV1040 can protect itself and other application equipment by turning off the PWM switch.

Figure 3 Basic boost application circuit

Figure 4 Evaluation board STEVAL-ISV006V2 circuit diagram

The STEVAL-ISV006V2 demo board is powered by a photovoltaic panel (200mW for PPK). According to the requirements of the application, the photovoltaic panel can be replaced by PPK up to 5W (VOC VOC selected PV panel). The demo board provides a simple charging status indicator, using 2 LEDs and 3 trimmers, which can be set according to specific application requirements.

Main features of the evaluation board STEVAL-ISV006V2

•High efficiency, monolithic step-up DC/DC converter

• Proprietary “disturbance observation” embedded MPPT algorithm

• Very low input voltage (0.3 V)

• Integrated N-channel and P-channel MOSFETs and low RON resistance

•Over current and over temperature protection

• Input polarity reverse protection

• LED charging status indication

• RoHS compliant