Product Brief DV04S7 Level Smart Charger With Dual-Battery Selector Features Level Smart Charger evaluation and development board with Dual-Battery Selector Supports System Management Bus specification and Level Smart Charger specifications rev..0 Supports the Smart Battery Selector specification and handles switching between external DC and one or two battery packs Supports stand-alone or in-system charging Charge voltage regulation range from 0 to 7.4V, current regulation range from 0 to.4a DC input range from 8 to 4V High-efficiency, low-ripple switch-mode design with high-side current sensing For safety, charging is suspended on charging command time-out or maximum temperature Interrupts host on change in selector status (battery or DC removed or replaced) General Description The DV04S7 Smart Charger Development System with Smart Battery Selector provides a development environment for Smart Charger devices compliant with System Management Bus, Smart Charger, and Smart Battery Selector specifications. The unit supports single- or dual-battery configurations. The two-chip design provides stand-alone or in-system charging of SMBuscompliant batteries or dumb batteries under host control. Using a high-efficiency switch-mode regulator, the DV04S7 charges from 0 to.4a and voltage compliance of 0 to 7.4V. The bq054 plus microcontroller high-side current sensing design can be modified to support other voltage and current requirements. Charging begins with a pre-charge qualification phase. The bq054 performs a low-current qualification test to detect batteries that have failed. The bq054 precharges undervoltage batteries for as long as 4 minutes to try to bring the pack up to minimum voltage (8V). If this time expires and the pack voltage is still under 8V, then the DV04S7 indicates a battery fault. The DV04S7, responding to Smart Charger commands, adjusts the current and voltage to the appropriate levels. Oct. 997 C Charging terminates when the battery signifies a fullcharge condition. If maximum charging temperature is exceeded or if communication with the battery is lost, the DV04S7 suspends charging until it receives new charging commands or until temperature returns to allowable levels. The microcontroller communicates with the SMBus and provides the voltage and current scaling to the bq054. The bq054 regulates both current and voltage using an internal PWM and reference circuit. Efficiencies greater than 85% are possible using the DV04S7 design, allowing for low-power dissipation. The DV04S7 design is ideal for in-system charging where high-efficiency is desired. The DV04S7-KT includes one EV00 Intelligent Battery Interface board and Windows-based PC software. The EV00 allows a PC to communicate with the smart battery and smart charger and display the status of each. A full data sheet for this product is available on our web site (http://www.benchmarq.com), or you may contact the factory for one.
DV04S7 Product Brief DV04S7 Board Schematic Oct. 997 C
Product Brief DV04S7 DV04S7 Board Schematic (Continued) Oct. 997 C
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