PDF《RT9527A》

RT9527A ? DS9527A-00 August

2017 www.

richtek.com

1 ? Copyright

2017 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. Single Cell Li-Ion Battery Charger with Adjustable Charging Current for Portable Applications Applications ? Cellular Phones ? Digital Cameras ? PDAs and Smart Phone ? Portable Instruments General Description The RT9527A is a low cost single-cell Li-ion charger for low current charge applications. The RT9527A can be powered up from an AC adapter or USB (Universal Serial Bus) port inputs. The RT9527A enters sleep mode when VIN power is removed. The RT9527A optimizes the charging task by using a control algorithm, which includes pre-charge mode, fast-charge mode and constant voltage mode. The charging task is kept in constant voltage mode to hold the battery in a full charge condition. The charge current is adjustable via an external resistor. The internal thermal feedback circuitry regulates the die temperature to optimize the charge rate for all ambient temperatures. The RT9527A features 28V maximum rating voltage for VIN. Other features include under-voltage protection and over-voltage protection for the AC adapter supply. The RT9527Ais available in the WDFN-8L 2x2 package. Features ? ? ? ? ? 28V Maximum Rating for AC Adapter ? ? ? ? ? Internal Integrated Power FETs ? ? ? ? ? Adjustable Charging Current ? ? ? ? ? Programmable Safe Charge Timer ? ? ? ? ? NTC Thermistor Input ? ? ? ? ? Battery Reverse Protection ? ? ? ? ? ISET Pin Short Protection ? ? ? ? ? Charge Status Indicator ? ? ? ? ? AC Adapter Power Good Status Indicator ? ? ? ? ? End of Charge Current is 10% of Fast-Charge Current ? ? ? ? ? Under-Voltage Protection ? ? ? ? ? Over-Voltage Protection ? ? ? ? ? Thermal Feedback Optimized Charge Rate ? ? ? ? ? Small Thermally Enhanced 8-Lead WDFN Package ? ? ? ? ? RoHS Compliant and Halogen Free Marking Information Simplified Application Circuit Ordering Information Note : Richtek products are : ? RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. ? Suitable for use in SnPb or Pb-free soldering processes. 4J : Product Code W : Date Code 4JW RT9527A Package Type QW : WDFN-8L 2x2 (W-Type) Lead Plating System G : Green (Halogen Free and Pb Free) RT9527A Input Power PGOOD CHG GND VIN Battery BAT Indicator TIMER ISET RT9527A

2 DS9527A-00 August

2017 www.richtek.com ? Copyright

2017 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. Functional Pin Description Functional Block Diagram Pin No. Pin Name Pin Function

1 VIN Supply voltage input. VIN can withstand up to 28V input.

2 PGOOD Power good status output. Active-low, open-drain output.

3 CHG Charger status output. Active-low, open-drain output. 4,

9 (Exposed Pad) GND Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation.

5 ISET Charge current setting.

6 TIMER Safe-charge timer setting.

7 TS Temperature sense input. The TS pin connects to a battery'

s thermistor to determine whether the battery is too hot or too cold for charging operation. If the battery'

s temperature is out of range, charging is paused until it re-enters the valid range.

8 BAT Charge current output for battery. Pin Configuration (TOP VIEW) WDFN-8L 2x2 VIN GND PGOOD BAT TS TIMER ISET CHG

7 6

5 1

2 3

4 8 GND

9 Sleep Mode Current Set Block OVP UVLO BASE Switch Well Thermal Circuit TIMER CC/CV/TR Multi Loop Controller Logic VREF IBIAS + - + - VIN VIN ISET BAT TS TMIER CHG PGOOD GND Too Cold Too Hot RT9527A