Key facts
- Brand
- SimCom
- Model
- SIM900A_HD
- Category
- Other Electronics
- Industry
- Electronics
- Documents
- 2
- Languages
- ZH
- Last added
- 2011-09-18
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SIMCOM SIM900A-HD CN V1.03 hardware design Manual
This manual describes the hardware architecture of the SIM900A GSM module, including pin assignments, power supply requirements, and the operation of key functions such as sleep modes and the real‑time clock. It is intended for engineers designing circuits that incorporate the module.
The document contains sections on power management (e.g., SLEEP#EHK, SLEEP#EH), RTC operation, voltage specifications, and detailed register tables. It also provides reset procedures and mechanical dimensions needed for board layout. This manual is written in Chinese.
All SimCom SIM900A_HD documents by type
Day-to-day operation, settings and troubleshooting. Start here if the product is already set up.
Questions answered in these manuals
What is the version and date of this manual?
The manual is version V1.01 dated 22.02.2010.
Which SimCom module does this manual cover?
It covers the SIM900A_HD GSM module.
