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POWER MANAGEMENT

SC905A

Pin #

Pin Name

I/O

Pin Function

1

IN2

Input

Input voltage terminal to VCORE LDO.

2

VCORE

Output

300mA LDO output for MSM core processor supply.

3

IN1

Input

Input voltage terminal to VPAD LDO.

4

VPAD

Output

300mA LDO PAD output to MSM I/O circuits.

5

ON

Input

Active high power on/off key. When the push button is closed it is shorted to battery.

6

HFPWR

Input

Power on input from accessory, active high.

7

SDA

Input/Output

8

SCL

Input

9

DGND

-

Digital ground.

10

DVIN

Input

Main digital input voltage terminal.

11

CHPWR

Input

Logic input. OR’d with ON and HFPWR.

12

EN_TCXO

Input

Logic input. External enable for VTCXO LDO. State is recorded in bit 0 of the status register.

13

EN_MOT

Input

Logic input. External enable for VMOT LDO. State is recorded in bit 2 of the status register.

14

VPSEL

Input

Default control for VPAD LDO supply. Ground for 2.20V default, tie high for 3.00V.

15

VCSEL

Input

Default control for VCORE LDO supply. Ground for 1.35V default, tie high for 1.80V.

16

PWRON

Output

Logic OR output of ON, HFPWR and PGOOD. Active high.

17

RESB

Output

Reset output. Active low.

18

PGOOD

Input

Logic input signal from MSM to indicate power is good, latches the SC905A on. Low disables the SC905A.

19

BP

Output

LDO bypass output. Bypass with a 0.1μF capacitor.

20

VBAT

Input

Main battery supply input terminal.

21

AGND

-

Analog ground pin.

22

VPLL

Output

LDO output for PLL power.

23

IN6

Input

Input voltage terminal for VPLL & VTX LDOs.

24

VTX

Output

LDO output for transmitter power.

25

VTCXO

Output

LDO output for TCXO power.

26

IN5

Input

Input voltage terminal for VTCXO & VRX LDOs.

27

VRX

Output

LDO output for receiver power.

28

VANA

Output

LDO output for analog power.

29

IN4

Input

Input voltage terminal to VANA LDO.

30

VCAM

Output

LDO output for camera power.

31

IN3

Input

Input voltage terminal to VCAM & VMOT LDOs.

32

VMOT

Output

LDO output voltage for vibrator motor power. Can also be a general purpose output.

T

Thermal Pad

-

Pad for heatsinking purposes. Connect to ground plane using multiple vias. Not connected internally.

Pin Descriptions