LTC4059A Linear Technology, LTC4059A Datasheet - Page 5

• Manufacturer Part Number: LTC4059A
• Description: 900mA Linear Li-Ion Battery Chargers
• Manufacturer: Linear Technology

PI FU CTIO S
GND (Pins 1, 7): Ground/Exposed Pad. The exposed
package pad is ground and must be soldered to the PC
board for maximum heat transfer.
Li CC (Pin 2, LTC4059): Li-Ion/Constant Current Input
Pin. Pulling this pin above V
thereby providing a constant current to the BAT pin. This
feature is useful for charging Nickel chemistry batteries.
Tie to GND if unused.
ACPR (Pin 2, LTC4059A): Open-Drain Power Supply
Status Output. When V
lockout threshold, the ACPR pin will pull to ground;
otherwise the pin is forced to a high impedance state.
BAT (Pin 3): Charge Current Output. Provides charge
current to the battery and regulates the final float voltage
to 4.2V. An internal precision resistor divider from this pin
sets this float voltage and is disconnected in shutdown
mode.
V
provides power to the charger. V
to 8V. This pin should be bypassed with at least a 1 F
capacitor. When V
voltage, the LTC4059 enters shutdown mode, dropping
I
BAT
CC
U
to less than 4 A.
(Pin 4): Positive Input Supply Voltage. This pin
U
CC
U
CC
is within 35mV of the BAT pin
is greater than the undervoltage
Li CC
CC
disables voltage mode
can range from 3.75V
PROG (Pin 5): Charge Current Program and Charge Cur-
rent Monitor Pin. Connecting a resistor, R
programs the charge current. When charging in constant-
current mode, this pin servos to 1.21V. In all modes, the
voltage on this pin can be used to measure the charge
current using the following formula:
EN (Pin 6): Enable Input Pin. Pulling this pin above the
manual shutdown threshold (V
the LTC4059 in shutdown mode, thus terminating a charge
cycle. In shutdown mode, the LTC4059 has less than 25 A
supply current and less than 1 A battery drain current.
Enable is the default state, but the pin should be tied to
GND if unused.
I
BAT
R
V
PROG
PROG
LTC4059/LTC4059A
• 1000
MS
www.DataSheet4U.com
is typically 0.92V) puts
PROG
, to ground
4059fa
5