Single-Chip Battery Management System for Cars

Maxim Integrated Products has announced MAX17843 battery management system (BMS). The MAX17843 is 12-channel, high-voltage smart sensor data-acquisition device. Electric vehicles (EVs), hybrid EVs, and plug-in hybrids rely on large lithium-ion battery packs filled with hundreds or even thousands of individual battery cells. With industry experts predicting that 25% of cars sold by 2025 will have electric engines, automotive OEMs and Tier 1s need an intelligent battery management system to enable safe, low cost solutions with robust communications.

MAX17843 meets the highest safety standards, adhering to ISO 26262 and ASIL D requirements (also applicable for ASIL C). Its differential universal asynchronous receiver/transmitter (UART) using capacitive isolation reduces bill of materials (BOM) costs and failure in time (FIT) rates. With this, designers can save up to 90% of their isolation BOM cost. The UART, with ultimate flexibility, enables robust communications in noisy environments. Using Maxim’s unique proprietary daisy-chain architecture and successive-approximation-register (SAR) analog-to-digital converter (ADC), the MAX17843 captures fast, accurate voltage measurements and delivers high EMC performance. It is applicable for a variety of automotive and EV powertrain applications.

Key advantages:

  • Safety: ISO 26262 and ASIL D certification, as well as TUV certification in design and management process; meets various BCI requirements; comprehensive diagnostics
  • Low System Cost: Internal cell balancing and UART reduces BOM costs compared to competitive solutions; only IC to allow capacitive or transformer isolation
  • Robust Communications: Reliable distributive and centralized CMC architecture with UART; Supports 100m daisy-chain segments and high noise immunity; Supports emission, ESD, and hot plug

The MAX17843 is available at Maxim’s website for $7.61 (1,000), The MAX17843EVKIT# evaluation kit is available for $1,000. The device operates over the -40°C to +125°C temperature range and is available in a 64-pin LQFP package (10mm x 10mm).

Maxim Integrated Products | www.maximintegrated.com

High-Side N-Channel FET Driver

Texas Instruments recently introduced the a single-chip, 100-V, high-side FET driver for high-power lithium-ion battery applications. Offering advanced power protection and control, the bq76200 high-voltage solution drives high-side N-channel charge and discharge FETs in batteries commonly used in energy storage systems and motor-driven applications (e.g., drones, power tools, e-bikes, and more). TexInst bq76200

Compared to 50-V low-side FET driver solutions, the 100-V high-side FET driver provides increased protection against possible inductive transient events in motor-driven applications. It also helps maintain constant battery monitoring and enhanced system diagnostics.

Key features and benefits:

  • Versatile supply voltage range: Compatible with a variety of battery architectures, capacities and voltage ranges from 8 to 75 V, with an absolute maximum of 100 V.
  • Advanced-protection FET control: The fast-switching feature minimizes fault response time and disables the discharge FET if a battery has been severely discharged.
  • Quick development time and reduced overhead: The adaptable driver works with small to large power FET arrays by simply scaling the charge-pump capacitor, reducing engineering overhead and speeding development time.
  • High integration and small package size: The bq76200 integrates a high-voltage charge pump and dual FET drivers into one 5 mm × 4.4 mm × 1 mm thin shrink small outline package (TSSOP).

The bq76200 can be used in conjunction with the bq76940 battery-monitoring family, allowing for the application to move to a high-side FET drive and ensure that communication is always possible. The bq76200 can also drive Texas Instrument’s CSD19531Q5A 100-V NexFET power MOSFET as in the bq76200 evaluation module.

The bq76200 is available now. The driver (six-pin TSSOP) costs $1.69 in 1,000-unit quantities.

Source: Texas Instruments

New Battery Pack Monitor Protects Multi-Cell Li-ion Batteries

Intersil Corp. recently announced the ISL94203 3-to-8 cell battery pack monitor that supports lithium-ion (Li-ion) and other batteries. The ISL94203 can monitor, protect, and cell balance rechargeable battery packs to maximize battery life and ensure safe charging and system operation. It works as a stand-alone battery management system for rechargeable Li-ion battery packs.Intersil-ISL94203

The ISL94203’s internal state machine has five preprogrammed stages that accurately control each cell of a battery pack to extend operating life. In addition, it integrates high-side charge/discharge FET drive circuitry.

Notable features and specifications:

  • Highest level of integration
  • Eight cell voltage monitors support Li-ion CoO2, Li-ion Mn2O4, Li-ion phosphate and other battery chemistries
  • Can operate as a standalone solution or with a microcontroller
  • Integrated charge pump controls cutoff FETs used to charge/discharge battery pack
  • Multiple cell voltage protection options up to 4.8 V
  • Programmable detection/recovery times for over-voltage, under-voltage, over-current, and short circuit conditions
  • Open wire detection
  • EEPROM storage for device configuration
  • Power saving algorithm activated when battery pack is not in use

 

The ISL94203 battery pack monitor is available now through Intersil’s worldwide network of authorized distributors. The ISL94203 comes in a 6 mm × 6 mm, 48-lead TQFN package, and is priced at $2.19 in 1,000-piece quantities. The ISL94203EVKIT1Z evaluation kit ($328) includes an evaluation board, interface board with USB-to-I2C interface, and software GUI that supports stand-alone operation or an external microcontroller.

Source: Intersil Corp.