ISL88731CHRTZ Renesas

BATTERY CURRENT DATASHEET ISL88731C FN6978 Rev 3.00 SMBus Level 2 Battery Charger June 8, 2011 The ISL88731C is a highly integrated Lithium-ion battery Features charger controller, programmable over the SMBus system 0.5% Battery Voltage Accuracy management bus (SMBus). The ISL88731C is intended to be used in a smart battery charger (SBC) within a smart battery 3% Adapter Current Limit Accuracy system (SBS) that throttles the charge power such that the 3% Charge Current Accuracy current from the AC-adapter is automatically limited. High SMBus 2-Wire Serial Interface efficiency is achieved with a DC/DC synchronous-rectifier buck converter, equipped with diode emulation for enhanced light Battery Short Circuit Protection load efficiency and system bus boosting prevention. The Fast Response for Pulse-Charging ISL88731C charges one to four Lithium-ion series cells, and delivers up to 8A charge current. Integrated MOSFET drivers Fast System-Load Transient Response and bootstrap diode result in fewer components and smaller Monitor Outputs implementation area. Low offset current-sense amplifiers - Adapter Current (3% Accuracy) provide high accuracy with 10m sense resistors. The - AC-Adapter Detection ISL88731C provides 0.5% end-of-charge battery voltage accuracy. 11-Bit Battery Voltage Setting 6 Bit Charge Current/Adapter Current Setting The ISL88731C provides a digital output that indicates the presence of the AC adapter as well as an analog output which 8A Maximum Battery Charger Current indicates the adapter current within 4% accuracy. 11A Maximum Adapter Current The ISL88731C is available in a small 5mmx5mm 28 Ld Thin +8V to +26V Adapter Voltage Range (0.8mm) QFN package. An evaluation kit is available to reduce Pb-Free (RoHS Compliant) design time. The ISL88731C is available in Pb-Free packages. Applications Related Literature Notebook Computers See AN1404 for ISL88731EVAL2Z and ISL88731CEVAL2Z Tablet PCs Evaluation Boards Setup Procedure Portable Equipment with Rechargeable Batteries 3.5 100 13.0 3.0 12.5 95 2.5 12.0 VCHG (V) 2.0 16.8V BATTERY 90 11.5 1.5 12.6V BATTERY 11.0 1.0 8.4V BATTERY 85 10.5 0.5 ICHG (A) 4.2V BATTERY 10.0 80 0.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 0 20 40 60 80 100 120 140 160 I (A) CHARGE TIME (MINUTES) OUT FIGURE 1. TYPICAL CHARGING VOLTAGE AND CURRENT FIGURE 2. EFFICIENCY vs CHARGE CURRENT AND BATTERY VOLTAGE FN6978 Rev 3.00 Page 1 of 26 June 8, 2011 BATTERY VOLTAGE EFFICIENCY (%)ISL88731C DCIN VCC LINEAR REFERENCE VDDP VREF 11 REGULATOR DACV VDDSMB DACV 6 DACS DACS SDA SMBUS 3.2V ACOK + 6 DACI DACI SCL - EN ACIN BUFF ICM CSSP LEVEL - EN SHIFTER GMS DACS CSSN 20x + BOOT ICOMP CSO UGATE CSOP LEVEL - SHIFTER GMI PHASE DC/DC CSON DACI 20x + CONVERTER LVB VDDP LVB DACV + GMV LGATE - PGND VFB 500k 100k EN CSSP GND VCOMP FIGURE 3. FUNCTIONAL BLOCK DIAGRAM AC ADAPTER TO SYSTEM RS1 CSSP CSSN UGATE RS2 TO BATTERY ACIN PHASE DCIN ISL88731C BOOT LGATE CSOP AGND CSON VFB ICOMP VCOMP PGND VDDP VREF PGND ACOK ICM SDA SCL VCC VDDSMB GND AGND FIGURE 4. TYPICAL APPLICATION CIRCUIT FN6978 Rev 3.00 Page 2 of 26 June 8, 2011 HOST