Circuit Design Inc. CDP02ER457 Manual De Usuario
OG_CDP-02E-R-457M_v11e Circuit Design, Inc.
19
OPERATION GUIDE
Application note
(Design guide for RF transmitter and receiver)
The following problems generally apply to radio modules
For stable operation, it is recommned to solder the shield case to PCB wide plane GND
Problem Solution
Touching or moving the antenna changes its impedance, which
causes variations in emission power. The variation appears as
distortion in the modulating signal and causes communication errors.
causes variations in emission power. The variation appears as
distortion in the modulating signal and causes communication errors.
Fix the position of the antenna to avoid moving it.
Positioning of the antenna is an important factor in operating the radio module
efficiently.
Positioning of the antenna is an important factor in operating the radio module
efficiently.
If a change in the circuit length occurs due to the on/off of switch etc.
in the electronic circuit connected to the radio module in the system
in which the radio module is integrated, the high frequency electric
potential can vary, disturbing the modulating signal, leading to
communication errors.
in the electronic circuit connected to the radio module in the system
in which the radio module is integrated, the high frequency electric
potential can vary, disturbing the modulating signal, leading to
communication errors.
Add bypass capacitors of 100 to 470 pF in the immediate vicinity of the switches.
Make the area beneath the radio module a ground pattern, utilizing part of the shield.
Make the area beneath the radio module a ground pattern, utilizing part of the shield.
If the power line and/or the signal input line are long the printed line
can be subject to high frequency noise. This noise may cause
communication errors.
can be subject to high frequency noise. This noise may cause
communication errors.
Block high frequency elements by adding a choke coil to each line.
Circuit Design’s receivers are designed to be vibration resistant.
However there is a limit to the amount of shock and vibration the
module can sustain due to its construction.
However there is a limit to the amount of shock and vibration the
module can sustain due to its construction.
In order to fix the receiver to the PCB strongly, solder the case to the PCB.
When using a radio receiver where vibration is always present, use a shock absorber
or fix the PCB at the vicinity of the four corners of the receiver module in addtion to
fixing the four corners of the PCB on which the radio module is mounted.
When using a radio receiver where vibration is always present, use a shock absorber
or fix the PCB at the vicinity of the four corners of the receiver module in addtion to
fixing the four corners of the PCB on which the radio module is mounted.
Circuit Design’s receivers are designed for high sensitivity. They will
obtain radio signals over long distances. On the other hand, the
receiver is sensitive to noise from the microcomputer and
surrounding digital circuits due to its high sensitivity.
obtain radio signals over long distances. On the other hand, the
receiver is sensitive to noise from the microcomputer and
surrounding digital circuits due to its high sensitivity.
Make the area beneath the radio module a ground pattern, utilizing part of the shield.
Block high frequency elements by adding a choke coil to each line.
Block high frequency elements by adding a choke coil to each line.
Soldering point