N900 Hardware Chipset

The chip known as 'Gaia' in the schematics is the companion chip to the processor.

Hardware

The TWL4030 (to be precise the TWL5030B, see [1] aka TPS65950) has USB PHY, power managment and audio codec.

The USB PHY isn't used and is handled by the nxp1707a [2] See more information on USB

It seems to be documented - not under this part number - at TIs website

A quick check indicates the I2C bus addresses match - see 13.3 in above datasheet.

If this is the correct part, the following description applies:

The TPS65950 contains;

Power management
- Several regulators - switched mode and LDO.
Audio codec
- Five DACs, two ADCs
- Several power amplifiers.
- Microphone amplifiers
USB tranciever
- Highspeed OTG compatible with integrated charge pump, and carkit support, designed for direct connection to the SoC.
an ac/USB charger
LED drivers
ADC
- ADC can measure both input voltages to device, or voltages connected externally.
RTC
GPIO
- This can support switches, keypads, ...