LTC4007 datasheet(6/20 Pages) LINER

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LTC4007

4007i

PI FU CTIO S

BAT (Pin 15): Battery Sense Input and the Negative

Reference for the Current Sense Resistor. A precision

internal resistor divider sets the final float potential on this

pin. The resistor divider is disconnected during shutdown.

CHEM (Pin 16):Select 4.1V or 4.2V cell chemistry by

connecting the pin to GND or open, respectively. Internal

µA pull-up to 5.3V. Can also be driven with open-

collector/drain logic levels.

FLAG (Pin 17): Active low open-drain output that indi-

cates when charging current has declined to 10% of

maximum programmed current. A pull-up resistor is

required if this function is used. The pin is capable of

sinking at least 100

µA.

CLP (Pin 18): Positive input to the supply current limiting

amplifier, CL1. The threshold is set at 100mV above the

voltage at the CLN pin. When used to limit supply current,

a filter is needed to filter out the switching noise. If no

current limit function is desired, connect this pin to CLN.

CLN (Pin 19): Negative Reference for the Input Current

Limit Amplifier, CL1. This pin also serves as the power

supply for the IC. A 10

µF to 22µF bypass capacitor should

be connected as close as possible to this pin.

TGATE (Pin 20): Drives the top external P-channel MOSFET

of the battery charger buck converter.

PGND (Pin 21): High Current Ground Return for the BGATE

Driver.

BGATE (Pin 22): Drives the bottom external N-channel

MOSFET of the battery charger buck converter.

INFET (Pin 23): Drives the Gate of the External Input PFET.

SHDN (Pin 24): Charger is shut down and timer is reset

when this pin is HIGH. Internal 10

µA pull-up to 3.5V. This

pin can also be used to reset the charger by applying a

positive pulse that is a minimum of 0.1

µs long.

LTC4007 датащи(PDF) 6 Page - Linear Technology