Datasheet

LTC2941
5
2941fa
pin FuncTions
SENSE
+
(Pin 1): Positive Current Sense Input and Power
Supply. Connect to the load/charger side of the sense
resistor. V
SENSE
+
operating range is 2.7V to 5.5V.
GND (Pin 2): Device Ground. Connect directly to the nega-
tive battery terminal.
SCL (Pin 3): Serial Bus Clock Input.
SDA (Pin 4): Serial Bus Data Input and Output.
AL/CC (Pin 5): Alert Output or Charge Complete Input.
Configured either as an SMBus alert output or charge
complete input by control register bits B[2:1]. At power-up,
the pin defaults to alert mode conforming to the SMBus
alert response protocol. It behaves as an open-drain logic
output that pulls to GND when a value in the threshold
registers is exceeded.
When configured as a charge complete input, connect
to the charge complete output from the battery charger
circuit. A high level at CC sets the value of the accumulated
charge (registers C, D) to FFFFh.
SENSE
–
(Pin 6): Negative Current Sense Input. Connect
SENSE
–
to the positive battery terminal side of the sense
resistor. The voltage between SENSE
–
and SENSE
+
must
remain within ±50mV in normal operation.
Exposed Pad (Pin 7): Do not connect.
block Diagram
REF CLK
BIDIRECTIONAL
INTEGRATOR
SENSE
–
INTERNAL
REFERENCE
GENERATOR
ACCUMULATED
CHARGE
REGISTER
PRESCALER
M
STATUS/
CONTROL
REGISTER
INTERNAL
OSCILLATOR
6
SENSE
+
V
SUPPLY
1
AL/CC
AL
5
GND
2
I
2
C/
SMBus
SCL
CC
SDA
2941 F02
3
4
Figure 2. Block Diagram of the LTC2941