Mar 30, 2011 12:39 GMT  ·  By
A comparison of the WWAN antennas in the GSM, CDMA, and Wi-Fi versions, respectively
   A comparison of the WWAN antennas in the GSM, CDMA, and Wi-Fi versions, respectively

Teardown experts iFixit acknowledge that Apple is essentially shipping 18 variations of the same iPad 2, though only three models can be deemed as distinct from one another.

Those are the WiFi-only, the GSM, and the CDMA iPad 2, with whatever on-board storage or color design the customer prefers.

“Our original iPad 2 teardown featured the black, 16GB, Wi-Fi only version,” iFixit notes.

The tinkerers say “There's absolutely no reason why we'd take apart 17 other iPads, but we felt it worthwhile to at least document the differences between the Wi-Fi only, GSM, and CDMA versions.”

According to their latest teardown, the most obvious difference between the GSM and CDMA versions of the iPad 2 is the microSIM slot.

Located in the upper left corner of the GSM iPad 2, the slot is machined “uniquely” in order to accommodate the SIM ejector mechanism and the SIM tray on GSM iPads.

Since the CDMA model doesn't rely on SIM cards to get its cellular signal, “[it] uses the circuitry on the WWAN board to relay user information.”

Because of this, the CDMA iPad has more empty space in the outer case above the WWAN board where the microSIM slot lays inside the GSM model.

By comparing the WWAN antennas in the GSM, CDMA, and Wi-Fi versions, iFixit found there is one more antenna in the CDMA version of the iPad 2.

This finding is similar to what they discovered in their Verizon iPhone 4 teardown.

“Obviously, the Wi-Fi version has no WWAN antenna and thus has no black plastic antenna window along the top edge of its case,” informs iFixit. “Instead, it makes do with solid aluminum.”

The repair shop finally proceeds to name the chips providing 3G connectivity for the CDMA iPad 2, which include: Qualcomm MDM6600 Baseband/RF Transceiver; Qualcomm PM8028 Power Management IC; Toshiba Y890A111222KA, likely a DRAM + flash MCP; Skyworks 77710 Power Amplifier Module; and Skyworks 77711 Power Amplifier Module.

Not one of these chips is a stranger to the CDMA iPhone 4, says iFixit.

As for the GSM iPad 2 3G, the board holds: Intel 36MY1EF containing 128Mb of Numonyx NOR flash and Elpida Mobile DDR SDRAM; Infineon 337S3833 Baseband Processor; Skyworks & TriQuint Transmit Modules; Infineon 338S0626 GSM/W-CDMA Transceiver; Broadcom BCM4751 Integrated Monolithic GPS Receiver.

The latter is noted as an upgrade from the BCM4750 used by Apple in the GSM iPhone 4.