EasyManuals Logo

SimCom SIM900 Hardware Design

SimCom SIM900
59 pages
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Page #31 background imageLoading...
Page #31 background image
SIM900 Hardware Design
3.7 RTC Backup
The RTC (Real Time Clock) power supply of module can be provided by an external capacitor or a battery
(rechargeable or non-chargeable) through the VRTC.
Note: If the RTC function is enabled, a battery or capacitor should be connected with the VRTC pin. If RTC
Backup is not needed, please don’t keep it floating, a 4.7uF capacitor is recommended to connect to this pin.
The following figures show various sample circuits for RTC backup.
RTC
Core
10K
SIM900
VRTC
Non-chargeable
Backup Battery
Figure 16: RTC supply from non-chargeable battery
RTC
Core
10K
SIM900
VRTC
Rechargeable
Backup Battery
Figure 17: RTC supply from rechargeable battery
RTC
Core
10K
SIM900
VRTC
Large-capacitance
Capacitor
Figure 18: RTC supply from capacitor
z Li-battery backup
Coin-type Rechargeable Capacitor such as XH414H-IV01E form Seiko can be used.
SIM900_HD_V1.05 06.23.2010
31

Table of Contents

Other manuals for SimCom SIM900

Questions and Answers:

Question and Answer IconNeed help?

Do you have a question about the SimCom SIM900 and is the answer not in the manual?

SimCom SIM900 Specifications

General IconGeneral
BrandSimCom
ModelSIM900
CategoryModem
LanguageEnglish