Datasheet LTC4070 (Analog Devices) - 6

link to page 7 LTC4070
PIN FUNCTIONS HBO (Pin 4):
High Battery Monitor Output (Active High). is discharged below 3.2V or rises above 3.5V. This pin HBO is a CMOS output that indicates that the battery is is driven high if VCC < VLBTH, and is driven low if VCC > almost fully charged and current is being shunted away (VLBTH + VLBHY). from BAT. This pin is driven high when VCC rises to within
DRV (Pin 7):
External Drive Output. Connect to the gate of VHBTH of the effective float voltage. The absolute value of an external PFET to increase shunt current for applications this threshold depends on ADJ and NTC, both of which which require more than 50mA charge current. Minimize affect the float voltage. HBO is driven low when VCC falls capacitance and leakage current on this pin. When not in by more than (VHBTH + VHBHY) below the float voltage. use, float DRV. Refer to Table 1 for the effective float voltage.
V GND (Pin 5, Exposed Pad Pin 9):
Ground. The exposed
CC (Pin 8):
Input Supply Pin. The input supply voltage is regulated to 4.0V, 4.1V, or 4.2V depending on the ADJ pin package pad must be connected to PCB ground for rated state (see the ADJ pin description for more detail). This thermal performance. pin can sink up to 50mA in order to keep the voltage regu-
LBO (Pin 6):
Low Battery Monitor Output (Active High). lation within accuracy limits. When no battery is present, LBO is a CMOS output that indicates when the battery decouple to GND with a capacitor, CIN, of at least 0.1µF.
BLOCK DIAGRAM
LTC4070 VCC ADJ 3-STATE PULSED DETECT LBO DUTY CYCLE < 0.002% – 30µs + CLK 1.5s OSC NTCBIAS + HBO RNOM 10k – NTC ADC T REF + DRV EA – GND 4070 BD Rev. D 6 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts