User's Manual

System Overview and Functional Block Descriptions
1320x-QE128EVB Reference Manual, Rev. 0.0
Freescale Semiconductor 3-5
3.3 Power Management and Measurement
To allow maximum versatility, the 1320x-QE128EVB can be powered via a DC source (typically an
AC-DC converter; nominally 5 Vdc), the USB node, or an on-board battery pack with 2 AA alkaline
batteries.
• The DC source or USB will automatically shutdown the battery supply
• The DC source and the USB power are regulated to 3.3 V, however, the raw battery pack voltage
directly supplies the circuitry
• All sources are isolated via diodes
• An on/off switch and a power-on LED are provided (see Section 4.2.2, “On/Off Switch (Hardware
Reset)”)
• Zero-ohm resistors are provided to allow isolation and measurement of various system components
(see Section 4.2.4, “Power Measurement”)
3.4 Low-cost 2.4 GHz IEEE 802.15.4 ISM Band Radio
The 1320x-QE128EVB provides a complete RF node which only requires a balun and antenna (external
to the MC1320x). The design uses a PCB printed metal F-antenna for an efficient, low cost solution.
Figure 3-4 shows the RF network external to the MC1320x.
The RF design provides:
• -1 to 0 dBm nominal output power, programmable from -27 dBm to +3 dBm typical
• Receive sensitivity of <-92 dBm (typical) at 1% PER, 20-byte packet, much better than the
802.15.4 Standard of -85 dBm
• Integrated transmit/receive switch
• Typical range (outdoors, line of sight) of 300 meters
• Optional on-board LC filter for harmonic filtering