User's Manual

System Overview and Functional Block Descriptions
1322x Network Node Reference Manual, Rev. 1.1
Freescale Semiconductor 3-3
The RF radio interface provides for low cost and high density as shown in Figure 3-3. An onboard balun
along with a TX/RX switch allows direct connection to a single-ended 50-Ω antenna. The integrated PA
provides programmable output power typically from -30 dBm to +2dBm, and the RX LNA provides -95
dBm sensitivity. This solution also has onboard bypass capacitors and crystal load capacitors for the
smallest footprint in the industry. All components are integrated into the package except the crystal and
antenna.
Figure 3-3. MC1322x RF Interface
Augmenting the core device on the Network Node are:
• Low-cost 2.4 GHz ISM Band radio
• 2.0 USB connection
• User interface with pushbuttons, LEDs and 128x64 pixel graphic LCD
• Versatile power sources and management
• Debug / development ports
• Audio subsystem
• GPIO connector for system expansion
Users are encouraged to reference the board schematic for the following sections.
3.3 Power Management and Measurement
To allow maximum versatility, the Network Node can be powered via a DC source (typically an AC-DC
converter; nominally 5 Vdc), the USB node, or an onboard 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 and Power
On Indicator”).
• Zero-ohm resistors are provided to allow isolation and measurement of various system components
(see Section 4.2.3, “Power Measurement”)
ANALOG
TRANSMITTER
ANALOG
RECEIVER
RF
TX/RX
SWITCH
BALUN
LNA
PA