gps-details

Airoha GNSS Chipsets

The Airoha AG3335 chipsets can be thought of as the descendants of the MediaTek MT3333.

A short article for ION GNSS+ 2022 describes the AG3335 series.

The SIMCOM GNSS solutions comparison table provides some details on features:

AG3331 is single band for GPS / GLONASS / BeiDou / QZSS , but isn’t used by Garmin or COROS.
AG3335M is multi-band (L1 + L5) but has no support the NavIC.
AG3335MN is single-band for GPS / GLONASS / Galileo / BeiDou / QZSS but it supports NavIC / IRNSS on L5.
AG3352 is another single-band chip on the Airoha website, which could well be used in future watches.

The availability of all systems + multi-band is due to the Airoha AG3335M.

The AG3335MN and AG3352 chipsets do not support multi-band, thus cannot be used in watches supporting multi-band.

AG3335MN is likely to have been used in all of the non multi-band Garmin watches released in 2022, except the Sony models:

fēnix 7X Solar was released in Jan 2022 and uses the AG3335MN, confirmed by the F Tipi teardown.
Venu Sq 2 was released in Sep 2022 and uses the AG3335MN, confirmed by the FCC teardown.

The Garmin watches since 2023 could be using either the AG3335MN or AG3352, but this is yet to be confirmed.

The availability of all systems + multi-band indicates that COROS are using the AG3335M chipset.

The PACE 3, APEX 2 Pro, VERTIX 2, and VERTIX 2S all have multi-band so they will be using the AG3335M:

PACE 3 was released in Aug 2023 and uses the AG3335M, confirmed by the FCC teardown.

The APEX 2 uses Airoha and was released in Nov 2022, but it does not have multi-band so probably the AG3335MN.

APEX 2 was released in Nov 2022 and probably uses the AG3335MN, only Airoha is confirmed by the FCC teardown.