Ebyte E78-400M22S User Manual

Contents

Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manualCopyright ©2012–2019，Chengdu Ebyte Electronic Technology Co,;Ltd 63 The test suite It is suggested that we can first use our testing base e78-tbl-01 specially made for E78 module, whichis convenient for users to use, and users can decide according to their own needs.6.Basic operation6.1 Hardware design It is recommended to use dc stabilized voltage power supply to supply power to this module. The ripple coefficientof the power supply should be as small as possible and the module should be grounded reliably. Please pay attention to the correct connection of the positive and negative poles of the power supply. Please check the power supply to ensure that it is between the recommended power supply voltage. If the maximumvalue is exceeded, the module will be permanently damaged. Please check the stability of the power supply, the voltage cannot fluctuate greatly and frequently; When designing power supply circuit for modules, it is often recommended to keep more than 30% allowance,which is conducive to long-term stable work of the whole machine. Module should be as far as possible away from the power supply, transformers, high frequency wiring and otherelectromagnetic interference large part; High frequency digital wiring, high frequency analog wiring and power supply wiring must avoid the Bottom of themodule. If it is really necessary to pass the Bottom of the module, assume that the module is welded to the TopLayer and copper is laid on the Top Layer in the contact part of the module (all copper is laid and well grounded). Itmust be close to the digital part of the module and wired on the Bottom Layer. Assuming that the module is welded or placed in Top Layer, it is also wrong to randomly line Bottom Layer or otherlayers, which will affect the spurious and receiving sensitivity of the module to varying degrees. It is assumed that there are devices with large electromagnetic interference around the module, which will greatlyaffect the performance of the module. According to the intensity of interference, it is suggested to stay away fromthe module appropriately. If possible, appropriate isolation and shielding can be done. It is assumed that the wiring around the module with large electromagnetic interference (high frequency digital,high frequency analog, power supply wiring) will also greatly affect the performance of the module. According tothe intensity of interference, it is suggested to stay away from the module. If possible, appropriate isolation andshielding can be done. If 5V level is used for communication line, 1k-5.1k resistance must be connected in series (not recommended, there