External NFC antennas with VTAP25 and VTAP50

VTAP reader modules (VTAP25‑MOD and VTAP50‑MOD) have no built‑in antenna, so you will need to choose or design and then integrate an external NFC antenna for any application.

If you incorporate a VTAP50‑OEM reader board into a new or existing product, you may decide to use an external antenna, in scenarios such as:

A VTAP50 reader module embedded inside other equipment, beyond standard antenna range, for instance within a turnstile;
Design preference for a custom antenna, for example an antenna that loops around a kiosk or vending machine touchscreen;

If your application requires an external antenna there are several things to consider including antenna design and tuning, potential interference with other components in your product, certifications needed for the region where the product will be deployed, and user experience.

This page discusses these issues and includes practical tips for using external antennas with a VTAP reader board or module.

Note: Only VTAP50‑OEM, VTAP50‑MOD and VTAP25‑MOD can use an external antenna.

The VTAP50‑OEM reader board is designed so that you can carefully break the integrated antenna from the board, if you decide to replace it with an external antenna. Alternatively, you can buy the VTAP50‑OEM without its antenna, which is sold as the VTAP50‑MOD reader module, that requires an external NFC antenna to function.

In the same way, a VTAP25‑MOD surface‑mount reader module does not have an integrated NFC antenna and requires an external antenna to function.

Note: The VTAP50‑OEM reader board has been RF/EMC tested with its integrated loop antenna, printed on the PCB. The VTAP25-MOD is RF/EMC tested with a reference host board.

When a new external antenna is attached to a VTAP50 reader, or a VTAP25 is embedded in a host board with a new antenna design, the new arrangement will require corresponding matching circuits and EMC approvals.