| Pin |
Signal |
Description |
| 1 |
GND |
Ground (-), internally connected with Pin 2 on iPod motherboard |
| 2 |
GND |
Audio & Video ground (-), internally connected with Pin 2 on iPod motherboard |
| 3 |
Right |
Line Out - R (+) (Audio output, right channel) |
| 4 |
Left |
Line Out - L(+) (Audio output, left channel) |
| 5 |
Right In |
Line In - R (+) |
| 6 |
Left In |
Line In - L (+) |
| 8 |
Video Out |
Composite video output (only when slideshow active on iPod Photo) |
| 9 |
S-Video Chrominance output |
for iPod Color, Photo only |
| 10 |
S-Video Luminance output |
for iPod Color, Photo only |
| 11 |
GND |
Serial GND |
| 12 |
Tx |
ipod sending line, Serial TxD |
| 13 |
Rx |
ipod receiving line, Serial RxD |
| 14 |
RSVD |
Reserved |
| 15 |
GND |
Ground (-), internally connected with pin 16 on iPod motherboard |
| 16 |
GND |
USB GND (-), internally connected with pin 15 on iPod motherboard |
| 17 |
RSVD |
Reserved |
| 18 |
3.3V |
3.3V Power (+)
Stepped up to provide +5 VDC to USB on iPod Camera Connector. If iPod is put to sleep while Camera Connector is present, +5 VDC at this pin slowly drains back to 0 VDC. |
| 19,20 |
+12V |
Firewire Power 12 VDC (+) |
| 21 |
Accessory Indicator/Serial enable |
Different resistances indicate accessory type:
1kOhm - iPod docking station, beeps when connected
10kOhm - Takes some iPods into photo import! mode
68kOhm - makes iPhone 3g send audio through line-out without any messages
500kOhm - related to serial communication / used to enable serial communications Used in Dension Ice Link Plus car interface
1MOhm - Belkin auto adaptor, iPod shuts down automatically when power disconnected Connecting pin 21 to ground with a 1MOhm resistor does stop the ipod when power (i.e. Firewire-12V) is cut. Looks to be that when this pin is grounded it closes a switch so that on loss of power the Ipod shuts off. Dock has the same Resister. |
| 22 |
TPA (-) |
FireWire Data TPA (-) |
| 23 |
5 VDC (+) |
USB Power 5 VDC (+) |
| 24 |
TPA (+) |
FireWire Data TPA (+) |
| 25 |
Data (-) |
USB Data (-) |
| 26 |
TPB (-) |
FireWire Data TPB (-) |
| 27 |
Data (+) |
USB Data (+)
Pins 25 and 27 may be used in different manner. To force the iPod 5G to charge in any case, when USB Power 5 VDC (pin 23) is fed, 25 must be connected to 5V through a 10kOhm resistor, and 27 must be connected to the Ground (for example: pin 1) with a 10kOhm resistor.
iPod 5G can also be forced to charge by attaching the data + and the data - pins to the 5v via a 10k Ohm resistor ( BOTH PINS) and connecting pin 16 to the 5v (ground). (Confirm!ed working with iPod 5G 20GB)
To charge an iPhone 3G / iPod Touch 2nd gen, usb data- (25) should be at 2.8v, usb data+(27) should be at 2.0v. This can be done with a few simple resistors: 33k to +5v (23) and 22k to gnd(16) to obtain 2v and 33k to +5v and 47k to gnd to obtain 2.8v. This is a notification to the iphone that it is connected to the external charger and may drain amps from the usb. |
| 28 |
TPB (+) |
FireWire Data TPB (+) |
| 29,30 |
GND |
FireWire Ground (-) |