2009 Fairchild Semiconductor Corporation
www.fairchildsemi.com
FSA9280A Rev 1.1.0
4
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Detection
Pin Descriptions
Name
Pin #
Type
Default
State
Description
USB Interface
DP_HOST
4
Signal Path
Open
D+ signal switch path, dedicated USB port to be connected to the resident
USB transceiver on the phone
DM_HOST
5
Signal Path
Open
D- signal switch path, dedicated USB port to be connected to the resident
USB transceiver on the phone
Audio Interface
Audio_L
2
Signal Path
Open
Left audio channel from mobile phone audio-out CODEC
Audio_R
1
Signal Path
Open
Right audio channel from mobile phone audio-out CODEC
MIC
3
Signal Path
Open
Connected to the mobile phone audio CODEC MIC input pin
UART Interface
TxD
7
Signal Path
Open
Transmitter (Tx) from resident UART on the mobile phone
RxD
6
Signal Path
Open
Receiver (Rx) from resident UART on the mobile phone
Connector Interface
ID_CON
20
Signal Path
Open
Connected to the USB connector ID pin and used for detecting
accessories or button presses
DP_CON
19
Signal Path
Open
Connected to the USB connector D+ pin; depending on the signaling
mode, this pin can be switched to DP_HOST, Audio_R, or RxD pins
DM_CON
18
Signal Path
Open
Connected to the USB connector D- pin; depending on the signaling
mode, this pin can switched to DM_HOST, Audio_L, or TxD pins
VBUS_IN
17
Power Path
N/A
Input voltage supply pin to be connected to the VBUS pin of the USB
connector
Power Interface
VBAT
11
Power
N/A
Input voltage supply pin to be connected to the mobile phone battery
output or to an internal regulator on the phone
VDDIO
9
Power
N/A
Baseband processor interface I/O supply pin
GND
Exposed
Center
Pad
Ground
N/A
Ground (center ground pad of package makes electrical contact)
Charger Interface
VBUS_OUT
15
Power Path
N/A
Output voltage supply pin to be connected to the source voltage pin on
the charger IC
CHG_DET
16
Open-Drain
Output
Hi-Z
Open-drain active LOW output, used to signal the charger IC that a
charger has been attached
Factory Interface
JIG
10
Open-Drain
Output
Hi-Z
Output control signal driven by the FSA9280A and used by the processor
for factory test modes
BOOT
8
CMOS
Output
LOW
Output control signal driven by the FSA9280A and used by the processor
for factory test modes
I
2C Interface
I2C_SCL
14
Input
Hi-Z
I
2C serial clock signal to be connected to the phone-based I2C master
I2C_SDA
13
Open-Drain
I/O
Hi-Z
I
2C serial data signal to be connected to the phone-based I2C master
INTB
12
CMOS
Output
LOW
Interrupt active LOW output used to prompt the phone baseband
processor to read the I
2C register bits, indicates a change in ID_CON pin
status or accessory attach status