Quectel M85 Operation & User’s Manual

M85 Hardware Design M85_Hardware_Design Confidential / Released 14 / 88 1) When the module works within this temperature range, the deviations from the GSM specification may occur. For example, the frequency error or the phase error will be increased. Table 2: Coding Schemes and Maximum Net Data Rates over Air Interface 2.4. Functional Diagram The following figure shows a block diagram of M85 and illustrates the major functional parts.  Radio frequency part  Seri ...

M85 Hardware Design M85_Hardware_Design Confidential / Released 83 / 88 Table 37: Terms and Abbreviations [12] Quectel_GSM_EVB_User_Guide GSM EVB user guide [13] Quectel_Module_Secondary_SMT_User_Guide Module secondary SMT user guide Abbreviation Description ADC Analog-to-Digital Converter AMR Adaptive Multi-Rate ARP Antenna Reference Point ASIC Application Specific Integrated Circuit BER Bit Error Rate BOM Bill Of Material BTS Base Transceiver Station CHAP Challenge H ...

M85 Hardware Design M85_Hardware_Design Confidential / Released 13 / 88 GPRS Connectivity  GPRS multi-slot class 12 (default)  GPRS multi-slot class 1~12 (configurable)  GPRS mobile station class B DATA GPRS  GPRS data downlink transfer: max. 85.6kbps  GPRS data uplink transfer: max. 85.6kbps  Coding scheme: CS-1, CS-2, CS-3 and CS-4  Support the protocols PAP (Password Authentication Protocol) usually used for PPP connections  Internet service ...

M85 Hardware Design M85_Hardware_Design Confidential / Released 53 / 88 In order to enhance the reliability and availability of the SIM card in application. Please follow the below criteria in the SIM circuit design:  Keep layout of SIM card as close as possible to the module. Assure the length of the trace as less than 200mm as possible.  Keep SIM card signals away from RF and VBAT alignment.  Assure the ground between module and SIM cassette short and wide. ...

M85 Hardware Design M85_Hardware_Design Confidential / Released 26 / 88 It is suggested to control the module’s main power supply (VBAT) via LDO enable pin to restart the module when the module has become abnormal. Power switch circuit like P-channel MOSFET switch circuit can also be used to control VBAT. 3.3.4. Monitor Power Supply The command AT+CBC can be used to monitor the supply voltage of the module. The unit of the displayed voltage is mV. For details, please ...

M85 Hardware Design M85_Hardware_Design Confidential / Released 28 / 88 1. Make sure that VBAT is stable before pulling down PWRKEY pin. The time of T1 is recommended as 100ms. 2. EMERG_OFF should be floated when it is unused. 3. For more details about the application of STATUS pin, please refer to the Chapter 3.15. 3.4.2. Power Down The following procedures can be used to turn off the module:  Normal power down procedure: Turn off module using the PWRKEY pin.  N ...