User's Manual

A8520E24A91 – Users Manual Page 5 of 28
Release Date: Dec 27
th
2010
1. Overview
The A8520E24A91 series modules are surface mount modules integrating a CC85xx
PurePath™ wireless audio transceiver with the CC2591 PA/LNA device for increased range
and an integral antenna. The module incorporates a crystal, the required RF matching and
filtering for FCC compliance as well as filtering on all digital lines for noise reduction and
sensitivity. The modules operate in the global non-licensed 2.4GHz ISM/SRD frequency band.
These radio modules are ideal for achieving low power, long range wireless connectivity without
having to deal with extensive Protocol, RF, antenna design and regulatory compliance, allowing
quick time to market. The modules are 100% tested to provide consistent performance.
The A8520E24A91 series modules have received regulatory approvals for modular devices in
the United States (FCC) and Canada (IC). The modular approval allows the end user to place
an A8520E24A91 module inside a finished product without having to perform costly regulatory
testing for an intentional RF radiator. Section 3 has information on the requirements for the end
user/integrator must fulfill to use the modules without intentional radiator regulatory testing.
The A85xxE91A91 is based on the CC85xx series chips and the CC2591 chip, both from Texas
Instruments. All control lines are provided at module level for full control of its operation. Please
see the CC85xx and CC2591 data sheet (www.ti.com) for how to operate, program and control
the module. The PurePath™ protocol is developed, by Texas Instruments, specifically for the
CC85xx series chips and specifically for digital audio distribution. At the extremes of its range,
the protocol provides graceful degradation of the audio signal usign algorithms like interpolation,
to make intermittent connectivity inaudible. Thus the A8520E24A91 series modules are not
suitable for strict data transport.
The module/protocol is configured and programmed by the OEM/Integrator to setup the specific
Codec chip used for audio conversion and to setup control buttons and manufacturer/network
addresses. This is described in detail in the CC85xx datasheet, users guide and PurePath™
documentation on Texas Instruments web (www.ti.com
). Specifics pertaining to calibrating the
transmit power from the module is covered in section 5.1.
The A8520E24A91 module measures 11x19x2mm and are footprint compatible with other
family members:
• A85xxE24A90 – ETSI compliant version similar to the A8520E24A91.
• A85xxR24A00 – Lower power consumption, shorter range modulens.