Cypress PowerPSoC MPPT LED驱动方案
Cypress 公司的PowerPSoC 系列LED驱动器采用CY8CLED04D0x器件和MPPT算法,优化电池充电,太阳能板开路电压21V,短路电流6A,12V电池,升压驱动器40V,电流2A.本文介绍CY8CLED04D0x主要特性,方框图, MPPT太阳能充电控制器方框图和详细电路图和主要元件.
The PowerPSoC family incorporates programmable system-on-chip technology with the best in class power electronics controllers and switching devices to create easy to use power-system-on-chip solutions for lighting applications.
All PowerPSoC family devices are designed to replace traditional MCUs, system ICs, and the numerous discrete components that surround them. PowerPSoC devices feature high performance power electronics including 1A 2 MHz power FETs, hysteretic controllers, current sense amplifiers, and PrISM/PWM modulators to create a complete power electronics solution for LED power management. Configurable power, analog, digital, and interconnect circuitry enables a high level of integration in a host of industrial, commercial, and consumer LED lighting applications.
This architecture integrates programmable analog and digital blocks to enable the user to create customized peripheral configurations that match the requirements of each individual application.
Additionally, the device includes a fast CPU, Flash program memory, SRAM data memory, and configurable I/O in a range of convenient pinouts and packages.
The PowerPSoC architecture, as illustrated in the block diagrams, comprises five main areas: PSoC core, digital system, analog system, system resources, and power peripherals which include power FETs, hysteretic controllers, current sense amplifiers,and PrISM/PWM modulators. Configurable global busing combines all the device resources into a complete custom system. The PowerPSoC family of devices have 10-port I/Os that connect to the global digital and analog interconnects, providing access to eight digital blocks and six analog blocks.
■ Integrated Power Peripherals
❐ Four internal 32V low side N-Channel power FETs
• RDS(ON)– 0.5Ω for 1.0A devices
• Up to 2 MHz configurable switching frequency
❐ Four hysteretic controllers
• Independently programmable upper and lower thresholds
• Programmable minimum on/off timers
❐ Four low side gate drivers with programmable drive strength
❐ Four precision high side current sense amplifiers
❐ Three 16-bit LED dimming modulators: PrISM, DMM, and PWM
❐ Six fast response (100 ns) voltage comparators
❐ Six 8-bit reference DACs
❐ Built-in switching regulator eliminates external 5V supply
❐ Multiple topologies including floating load buck, floating load buck-boost, and boost
■ M8C CPU Core
❐ Processor speeds up to 24 MHz
■ Advanced Peripherals (PSoC® Blocks)
❐ Capacitive sensing application capability
❐ DMX512 interface
❐ DALI interface
❐ I2C master or slave
❐ Full-duplex UARTs
❐ Multiple SPI masters or slaves
❐ Integrated temperature sensor
❐ Up to 12-bit ADCs
❐ 6 to 12-bit incremental ADCs
❐ Up to 9-bit DACs
❐ Programmable gain amplifiers
❐ Programmable filters and comparators
❐ 8 to 32-bit timers and counters
❐ Complex peripherals by combining blocks
❐ Configurable to all GPIO pins
■ Programmable Pin Configurations
❐ 25 mA sink on all GPIO and function pins
❐ Pull up, pull down, high Z, strong, or open drain drive modes on all GPIO and function pins
❐ Up to 10 analog inputs on GPIO
❐ Two 30 mA analog outputs on GPIO
❐ Configurable interrupt on all GPIO
■ Flexible On-chip Memory
❐ 16K Flash program storage 50,000 erase and write cycles
❐ 1K SRAM data storage
❐ In-System Serial Programming (ISSP)
❐ Partial Flash updates
❐ Flexible protection modes
❐ EEPROM emulation in Flash
■ Complete Development Tools
❐ Free development software: PSoC Designer 5.0™
❐ Full featured, In-Circuit Emulator and Programmer
❐ Full speed emulation
❐ Complex breakpoint structure
❐ 128 kBytes trace memory
■ Visual Embedded Design
❐ LED based express drivers
❐ Binning compensation
❐ Temperature feedback
❐ Stage LED lighting
❐ Architectural LED lighting
❐ General purpose LED lighting
❐ Automotive and emergency vehicle LED lighting
❐ Landscape LED lighting
❐ Display LED lighting
❐ Effects LED lighting
❐ Signage LED lighting
■ Device Options
• Four internal FETs with 0.5A and 1.0A options
• Four external gate drivers
• Four external gate drivers
• Three internal FETs with 0.5A and 1.0A options
• Three external gate drivers
• Three external gate drivers
• Two 1.0A internal FETs
• Two external gate drivers
• One 1.0A internal FET
• One external gate driver
■ 56-pin QFN Package
Cypress’ Integrated MPPT Solar Charge Controller – LED Driver is a battery charger and LED driver controller for standalone PV (photovoltaic) systems. This controller features a smart tracking algorithm that maximizes energy harvest from solar panels. The controller also prevents over charge or deep discharge. It provides automatic load control for the external load connected to the controller board.
This optimized battery charging process increases battery life, minimizes battery maintenance, and improves system performance.
Maximum power point tracking, referred to as MPPT, is an electronic system that operates the photovoltaic modules to produce maximum power. MPPT varies the electrical operating point of the modules and enables them to deliver maximum available power. The additional power harvested increases the current available for battery charging. MPPT can be used in conjunction with a mechanical tracking system, but the two systems are completely different.
Figure 1 shows the V-I (bold trace) and P-V (dotted trace) characteristics of a typical 75W panel at 25℃ and 1000W/m2 of irradiance. A conventional charge controller charges a battery by placing it directly across the solar module. This causes the panel to operate at the battery voltage, thus delivering lower power than what it can actually deliver.
Instead of connecting the battery directly to the photovoltaic modules, Cypress’ MPPT solar charge controller modulates the battery charging current. This is done to operate the module at the voltage where it is capable of producing a maximum power of 75W. This can be done regardless of the value of battery voltage. If the battery voltage is 12V, the voltage at which the maximum power is drawn from the solar module is 17V; the maximum current the module can deliver is 4.5 amperes. This is an increase in battery charging current of up to 1.875 amperes. It significantly improves the ampere-hours delivered to a battery. The greater the difference in the module voltage at which it delivers maximum power and battery voltage, greater is the increase in the battery charging current.
Power delivered by the solar panel is converted at a voltage level that can drive charging current into the battery. PowerPSoC generates the necessary control signal to drive a synchronous buck converter that converts the solar panel power to charge the battery. The MPPT algorithm embedded in the PowerPSoC takes voltage and current feedback from the panel and adjusts the control signals to operate the panel at its peak power. The PowerPSoC also takes care of the battery charging process and turns the LEDs ON or OFF based on battery condition and Load switch status. The PowerPSoC can be programmed using the on-board ISSP connector. The software can be debugged using an on-board OCD (On Chip Debugger) connector (optional). OCD provides real time emulation capability of the circuit by placing breakpoints in the code. Breakpoints are placed at relevant places in the code; code can be stepped through, in order.
The solar charge controller also has a board protection feature that protects the board from battery short circuits, battery open, and battery/panel reverse connections.