14.0 Required External Components

20111510

14.1 CHARGE PASS TRANSISTOR (Q1)

Q1 is a PNP device capable of sustaining a minimum of 0.8W continuous power dissipation. ON Semiconductor MMJT9435 or

equivalent is to be used.

14.2 DRIVER TRANSISTOR AND BIAS RESISTORS (R2, R3 AND R5)

The NPN transistor is a MMBT3904LT1 type (or equivalent) with a BV

collector resistors (R3 and R5) are 75

Ω each. The power rating on R3 and R5 is to be at least 100 mW.

14.3 EXTERNAL CHARGER SENSE RESISTOR (R4)

Value = 2K total for R4A+ R4B. Two series resistors are used for higher reliability. Having two resistors in series significantly

reduces the probability of the entire 2K of resistance being shorted. The power rating of R4A and R4B needs to be at least

100 mW each.

14.4 CAPACITORS

The capacitor C1 is to be a 0.1 uF, which is used for both RF bypass and ESD protection reasons. The capacitors C2 and C3 are

0.1 uF capacitors, which are used in the application to keep M4 from momentarily opening when the ground plane of the phone

takes an ESD discharge. These capacitors C2 and C3 should be adjacent to the pins on the IC. C4 on Radio B+ is 10uF.

14.5 FUSE (F1)

Parameter

Min

Typ

Max

Units

Operating Temperature

−55

25

90

˚C

Insulation Resistance (After Opening)

10000

-

-

Ω

Opening Time at 25˚C

100% of Ampere Rating

200% of Ampere Rating

300% of Ampere Rating

4

5

0.2

-

-

-

-

-

-

Hour

Sec.

Sec.

Ampere Rating

2.0

A

Nominal Resistance Cold

a

0.036

Ω

Melting I

0.104

A

Volting Rating

32

V

35

A

15.0 Electrical Characteristics

15.1 GENERAL SPECIFICATION AND ABSOLUTE MAXIMUM RATINGS (Note 1)

Symbol

Parameter

Min

Typ

Max

Units

Pin Voltage Ratings

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