16.0 Physical Dimensions ................................................................................................................................ 21

6.0 Connection Diagrams and Package Marking

20111502

MicroSMD Top View

See NS Package Number TLA25

20111503

MicroSMD Bottom View

7.0 LM3655 Pin Description

Pin #

Name

I/O

Type

Description

A1

CHEMISTRY

Input

Logic

A low input sets the constant voltage and termination voltage to the

lower V

voltage level V

Ω pull-down

resistor and can be controlled by a peripheral IC or can be tied directly

to B+ or GND.

A2

HIB_DISB

Input

Logic

This pin is internally pulled up to the CELL pin by a 100K resistor.

When this pin is momentarily pulsed low, Hibernate mode is exited,

which turns on M4.

A3

HIB_EN

Input

Analog

The IC is configured in hibernation mode, when this pin is pulled high

after a debounce period. Activating hibernation mode turns off the

internal M4 transistor.

A4

EXT_PWR_ON

Output

Logic

EXT_PWR_ON is a push-pull output. It is a logic 1 (Radio_B+ voltage

level) when the cell has reached the V

while the charger is connected and the battery is present.

A5

CNTRL

Output

Analog

This output pin regulates the charger current by controlling the base

voltage of the external drive and pass transistors Q2 and Q1.

B1, C1, C2,

D1

RADIO

Output

Analog

This is the power supply terminal for the phone. ALL load current from

the cell must be sourced from this pin.

B2

NC

This pin must be left floating. It needs to be connected to a non

connected PCB pad for heat sinking. It cannot be connected to other

NC pins.

B3, C3, D3

CELL

I/O

Analog

These pins need to be connected to the cell’s positive terminal.

B4, C4, D4

V

IN

Input

Analog

Input from the pass transistor Q1.

B5, C5, D5

GND

Ground

Ground pin for the circuit and CELL-

D2

NC

This pin must be left floating. It needs to be connected to a non

connected PCB pad for heat sinking. It cannot be connected to other

NC pins.

E1

DISABLE

Input

Logic

A logic high applied to this input disables the charging. A logic low

enables it. This pin has an internal 100 K

Ω pull-down resistor and can

be left unconnected.

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