STBC21FTR

STBC21 LI+ battery charger with thermal regulation Datasheet production data Features Programmable charge current up to 1.1 A Floating voltage limitation outside the safety temperature range PSE fully compatible Low battery voltage detection for pre-charge setting HTSSOP-14 (5 x 4.4 mm) Automatic recharge Two charge status output pins moves to the fast-charge procedure with a current Constant current / constant voltage operation programmable by an external resistor up to 1.1 A. No external MOSFET, sense resistors or When the battery reaches the value of the floating blocking diode required voltage the charger enters constant voltage Reverse current blocking (50 A max.) mode. Even in this mode a protection timer is active to avoid risks due to damaged batteries. Short-circuit protection and thermal shutdown The charge cycle is automatically terminated Less than 1 mA supply current in standby when the current flowing to the battery reaches mode the value programmed in NVM. There is also a Reversed battery polarity protection programmable lag time after the termination to maximize the battery charge. An internal block IC interface for charging parameters regulates the battery floating voltage when its programming temperature is outside the safety range between ESD: HBM 2 kV, CDM 500 V on every pin 10 C and 45 C, (JEITA/PSE regulation). The HTSSOP-14 (5 x 4.4 mm) package available floating voltage inside the safety range is set, by default, at 4.2 V. If the external power supply is -25 C to 125 C operative junction removed, the STBC21 turns off and a 50 A temperature (max.) current can flow from the battery to the device. The device also has an undervoltage Description lockout and automatic recharge capability which can be enabled/disabled by setting a bit in NVM. The STBC21 is a constant current/constant Two separate status pins allow a lot of information voltage charger for single cell Li-Ion batteries. to be gotten based also on flashing frequency and Most of the charging parameters, including duty cycle. The STBC21 also includes a reversed floating voltage, pre-charge and termination battery polarity protection to prevent damage due current are programmable in NVM memory. While to incorrect battery insertion. The package is a fast charging current is programmed using an HTSSOP-14 (5 x 4.4). external resistor. The constant current process is split into three phases depending on the battery Table 1. Device summary voltage. If the battery voltage is below 3.0 V, the charging current is set to a programmable value Order code Package Packaging below 200 mA. A timeout of 60 minutes is used in STBC21FTR HTSSOP-14 Tape and reel this phase to detect faulty batteries. When the battery voltage goes above 3.0 V, the charger June 2012 Doc ID 023256 Rev 1 1/54 This is information on a product in full production. www.st.com 54Contents STBC21 Contents 1 Block diagram 6 2 Pin configuration 8 3 Maximum ratings 9 4 Electrical characteristics 10 5 Detailed description 13 5.1 Operation mode 14 5.2 Battery connection detection 15 5.3 Start of charge . 16 5.4 Fast-charge programming 17 5.5 Charge auto-limitation . 17 5.6 PHC pin functionality 21 5.7 Alarms . 22 5.8 Reversed battery polarity protection . 25 5.9 Temperature protection 25 5.10 IC data transfer 26 5.10.1 Sequential registers write: . 27 5.10.2 Sequential registers read: . 28 6 ESD requirements 29 Appendix A Register configuration and access mode description 30 Appendix B Charging parameters . 31 Appendix C Charging control 36 Appendix D Temperature thresholds 37 Appendix E LED configurations diversified for customer (each customer one pattern) . 40 2/54 Doc ID 023256 Rev 1