PS501-based intelligent battery system (part 1)
Introduction
Microchip Technology Introduces PS501 is the smart intelligent management of battery for 2-4 Li-ion and lithium polymer batteries, or 6-12 nickel metal hydride and nickel cadmium batteries, can accurately calculate the remaining battery ability, the ability of full charge, and the forecasts can be run time and battery charging time required to complete, providing the battery monitoring system to ensure security, advanced battery balancing function may extend battery life and time. The communication protocol compliance with SMBus 1.1 and 1.1 Smart Battery SBdata instructions set. Dell XPS M1210 battery Dell XPS M1330 battery
Characteristics and Pin Description
● Features
Support 2-4 batteries and nickel from June to December lithium.
Based on PIC18F MCU core, field-programmable Lithium Ion / Lithium Polymer / Ni smart battery gauge.
Follow the SMBus 1.1 and SBdata 1.1.
Precision 16-bit Δ-Σ A / D conversion, the precision of current measurement is less than 1 mA.
18V maximum input voltage, terminal voltage measurement can be connected directly to the core battery.
Programmable I / O for the LED driver and the second count and protection against discharge and complete security protection.
Various elements of battery, the user can configure a different battery model.
Standard battery capacity measurement is less than 1%.
Advanced end of discharge (EOD) method of judging.
16KB of flash memory and EEPROM 256Byte.
High precision internal oscillator.
Very low energy consumption, energy consumption for work 200μA, 100μA that the sampling method, sleeping only 0.5μA.
Improved protection against ESD.
12 I General purpose programmable I / O ports, including two high voltage (18V max) Output open drain.
Integration and outside temperature sensor, detecting the temperature to reach both.
Integrated circuit current balance of 8.4mA maximum battery balancing and control external battery balance. Dell XPS M140 battery Dell XPS M1530 battery
● Pin Description
PS501 TSSOP28 package using lead-free RoHS EU and national environmental requirements, the pin of Figure 1. Ultra-small size TSSOP (7.85mm x 10.2mm) PCB space savings, easy installation in the battery pack of different sizes, in Figure 2.
PS501 Pin Function Description
PS501 internal structure and operating principle
● internal structure PS501
● heart of processor / memory
PS501 using the PIC18 8 位 RISC core resources, including 16KB of flash memory and EEPROM 256Byte were used to store programs and data and settings. Both the memory can be reprogrammed by the SMBus interface, without the need for special programming interface. PS501 every room in the factory have a good burning program bootloader for different types of electrical equipment, different characteristics of the core battery, and various capabilities such as configuration information you can use Powertool500 software settings produce different firmware, the battery plant in Download the firmware, if the factory battery can be quickly and easily to different characteristics of the core battery, a device to different host computer to change the firmware, without any circuit changes. Dell XPS M170 battery Dell XPS M1710 battery
● A / D converter
PS501 using high precision A / D converter to carry current, voltage and temperature measurement. A / D is calibrated to eliminate gain errors and offset errors. PS501-based smart battery management PCBA in the production process in addition to the scene to download the firmware, but also on the A / D converters and calibration of silicon clock oscillator, calibration include: the sampling the battery voltage, the base voltage of each battery string sample temperature sampling, external and internal, sampling ongoing and silicon oscillator. Therefore, it is the precision components, PCB design, the cumulative error may be caused by alignment to maximize the correction to ensure sampling of each PCBA on the physical quantity is correct, but all time spent in this process is only 15 years, and all all processes automatically, without manual intervention. Dell XPS M1730 battery Dell XPS M2010 battery
● model PowerSmart battery firmware /
Flash memory has been used to cure PowerSmart battery management firmware development. The firmware uses sophisticated algorithms and three-dimensional cell models, the model contains more than 250 types of parameters, it can also self-discharge, temperature and other factors to compensate. In addition, PS501 in the charging / discharging also implemented a number of capacities and reduce operation error correction to improve accuracy, improve the fuel gauge and performance monitoring load. It ensures the accuracy of the information capacity of the battery, and the error is less than 1% of the forecast in real time. Flash programmable features make the design without changing the principle of silicon can be achieved quickly and generates user version of the firmware upgrade. PS501 battery depending on the chemical nature of specific applications for easy customization.
PowerSmart provides a range of standard configuration files, can be used to configure a variety of rechargeable batteries and battery popular applications. Figure 4 and Table 1 at different temperatures, the discharge rate of the different voltage discharge end PS501 3D model and an example of setting an internal table. dell inspiron 6000 battery dell inspiron 630m battery
● SMBus interface command / SBdata
PS501 include a full SMBus v1.1 engine SMBus communication agreement, all current laptops laptop batteries and communication must follow the communication protocol. SMBUS protocol I2C communication is a subset of the use of communications processors with an I2C interface or I2C communication interface with the methods of simulation software, can easily read the data SBdata PS501, applied to various electronic products.
● the integration of accurate time base
PS501 silicon oscillator with high accuracy, no external clock oscillator can be calculated from the time of discharge and the capacity at specific times. The internal oscillator of silicon in the production of the battery can be calibrated by the user.
● Temperature detection
When PS501 battery is close to being monitored, you can use on-chip integrated temperature sensor to reduce the number of devices, users may choose to provide through the device pin external thermistor to monitor temperature. PS501 also supports two sensors inside and outside the sample, respectively, to monitor the temperature of two different places and different conditions can be made through the GPIO temperature protection. dell inspiron 5150 battery dell inspiron 5160 battery
● Universal I / O
PS501 provides 12 programmable digital input output pins /. An 8-pin can be used as LED output to show the state of charge (SOC), or directly control the external load circuit, or the lithium-ion battery to provide extra security. Of course, they can be used as general purpose input output pins /. In these pins, there are two I / O pins is an open-drain output, so can be used directly on the drive FET or other high voltage applications.
PS501-house 8.4mA maximum current balance sufficient to meet the large capacity battery for the balance required function, PS501 to I shared I / O control circuit external balance, the balance of the size defined by the user of the current command. In addition, general-purpose I / O can also be used as a work in battery low volume, low battery alarm for audible indication. dell inspiron 2600 battery dell inspiron 2650 battery