Hardware

1G Nano:

2G Nano:

Component	Details
CPU	An Apple-branded ARM processor marked 337S3291 8701. It is probably a Samsung S5L8701B05, because the markings share an S for Samsung, and 8701 for the part number.
Codec	Another Apple rebranded chip marked APPLE 33850310, probably a Wolfson. Same size and position as previous Wolfson chip. (Wolfson WM8750S? - unknown source)
Utility Flash ROM	SST SST39WF800A,stores Disk Mode, Diagnostic Mode and the code to flash this chip. The data of this chip is decrypted too. See Encryption.
NAND Flash	Depends on the iPod. Common ones are the Samsung K9MBG08U5M and the Hynix HY27UW08BGFM.
PM	National's LM34910 switching power supply and Linear's LTC4066 for charging the battery off USB power.

3G Nano:

4G Nano:

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