LTC3305_15 Datasheet, PDF (9/28 Pages) Linear Technology – Lead-Acid Battery Balancer

LTC3305
Pin Functions
BOOST (Pin 1): Charge Pump Output. Decouple with a
10µF capacitor to V4.
V4 (Pin 2): Positive terminal of Battery 4 connects to this
pin. Battery 4 is connected between V4 and V3. Decouple
with at least a 10µF capacitor to V3.
V3 (Pin 3): Positive terminal of Battery 3 connects to this
pin. Battery 3 is connected between V3 and V2. Decouple
with at least a 10µF capacitor to V2.
AUXP (Pin 4): Positive terminal of the auxiliary cell con-
nects to this pin. Decouple with at least a 10µF capacitor
to AUXN.
AUXN (Pin 5): Negative Terminal of the auxiliary cell con-
nects to this pin.
V2 (Pin 6): Positive terminal of Battery 2 connects to this
pin. Battery 2 is connected between V2 and V1. Decouple
with at least a 10µF capacitor to V1.
V1 (Pin 7): Positive terminal of Battery 1 connects to this
pin. Battery 1 is connected between V1 and GND. Decouple
with at least a 10µF capacitor to GND.
NGATE1 (Pin 8): NMOS1 Gate. Connect to the gate terminal
of external NMOS switch.
NGATE2 (Pin 9): NMOS2 Gate. Connect to the gate terminal
of external NMOS switch.
NGATE3 (Pin 10): NMOS3 Gate. Connect to the gate ter-
minal of external NMOS switch.
NGATE4 (Pin 11): NMOS4 Gate. Connect to the gate ter-
minal of external NMOS switch.
NGATE5 (Pin 12): NMOS5 Gate. Connect to the gate ter-
minal of external NMOS switch.
NGATE6 (Pin 13): NMOS6 Gate. Connect to the gate ter-
minal of external NMOS switch.
NGATE7 (Pin 14): NMOS7 Gate. Connect to the gate ter-
minal of external NMOS switch.
NGATE8 (Pin 15): NMOS8 Gate. Connect to the gate ter-
minal of external NMOS switch.
NGATE9 (Pin 16): NMOS9 Gate. Connect to the gate ter-
minal of external NMOS switch.
BATX (Pin 17): This pin along with BATY indicates which
battery in the stack is currently being balanced and to
which the fault outputs apply. Open Drain Output.
BATY (Pin 18): This pin along with BATX indicates which
battery in the stack is currently being balanced and to
which the fault outputs apply. Open Drain Output.
OVFLT (Pin 19): Overvoltage Fault. This pin is pulled low
when an overvoltage fault condition is detected on a bat-
tery. Open Drain Output.
UVFLT (Pin 20): Undervoltage Fault. This pin is pulled
low when an undervoltage fault condition is detected on
a battery. Open Drain Output.
BAL (Pin 21): Balancing Indicator. This pin is pulled low
while the balancing operation is being performed and is
in its high impedance state when the part is disabled or
the part is in the sleep state. Open Drain Output.
DONE (Pin 22): Done Indicator. This pin is pulled low when
all the batteries in the stack are balanced. This pin is in its
high impedance state in shutdown. Open Drain Output.
PTCFLT (Pin 23): PTC Fault. This pin is pulled low when the
voltage across the PTC thermistor exceeds 1V. It is in its
high impedance state at all other times. Open Drain Output.
CTOFF (Pin 24): A capacitor from this pin to GND programs
the retry time in timer mode. Connect to GND if MODE = 1.
CTON (Pin 25): A capacitor from this pin to GND programs
the maximum time for the balancing operation in timer
mode. Connect to GND if MODE = 1.
CTBAT (Pin 26): A capacitor from this pin to GND programs
the maximum time an individual battery in the stack is con-
nected to the auxiliary cell during the balancing operation.
V_L (Pin 27): Low Voltage Fault Threshold. A resistor from
this pin to GND programs the low voltage fault threshold
for each battery in the series stack. Works in conjunction
with the I_SET pin.
V_H (Pin 28): High Voltage Fault Threshold. A resistor from
this pin to GND programs the high voltage fault threshold
for each battery in the series stack. Works in conjunction
with the I_SET pin.
3305f
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