Design Notes For The Xbee/Xbee-Pro Rf Module; Power Supply Design - Digi XBee Product Manual

Table 2: Pin assignments for the XBee-PRO Modules
(Low-asserted signals are distinguished with a horizontal line above signal name.)
Pin # Name
7 PWM1
8 [reserved]
9 DTR / SLEEP_RQ/ DI8
10 GND
11 AD4 / DIO4
12 CTS / DIO7
13 ON / SLEEP
14 VREF
15 Associate / AD5 / DIO5
16 RTS / DIO6
17 AD3 / DIO3
18 AD2 / DIO2
19 AD1 / DIO1
20 AD0 / DIO0
* Function is not supported at the time of this release
Notes
• Minimum connections: VCC, GND, DOUT and DIN
• Minimum connections for updating firmware: VCC, GND, DIN, DOUT, RTS and DTR
• Signal direction is specified with respect to the module
• The module includes a 50 kpull-up resistor attached to RESET
• You can configure several of the input pull-ups using the PR command
• Leave any unused pins disconnected

Design notes for the XBee/XBee-PRO RF Module

The XBee modules do not specifically require any external circuitry or specific connections for proper
operation. However, there are some general design guidelines that are recommended for help in
troubleshooting and building a robust design.

Power supply design

Poor power supply can lead to poor radio performance, especially if the supply voltage is not kept
within tolerance or is excessively noisy. To help reduce noise, we recommend placing a 1.0 μF and 8.2
pF capacitor as near as possible to pin 1 on the XBee. If using a switching regulator for the power
supply, switching frequencies above 500 kHz are preferred. Power supply ripple should be limited to
a maximum 100 mV peak to peak.
XBee / XBee-PRO RF Modules 802.15.4 Product Manual
Direction Description
Either PWM output 1
- Do not connect
Either Pin sleep control line or digital input 8
- Ground
Either Analog input 4 or digital I/O 4
Either Clear-to-send flow control or digital I/O 7
Output Module status indicator
Input Voltage reference for A/D inputs
Either Associated indicator, analog input 5 or digital I/O 5
Either Request-to-send flow control, or digital I/O 6
Either Analog input 3 or digital I/O 3
Either Analog input 2 or digital I/O 2
Either Analog input 1 or digital I/O 1
Either Analog input 0, digital IO 0
Design notes for the XBee/XBee-PRO RF Module
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