Smart Machine Smart Decision
SIM800L(MT6261)_Hardware Design_V1.01
41
2016-07-07
KBR4
KBR3
KBR2
KBR1
KBR0
KBC0
KBC1
KBC2
KBC3
KBC4
Module
Figure 37: 25 keys reference circuit
Note
:
According to the traditional 5*5 to design buttons, when there is spare KBC or KBR, customer can execute AT command
to define as GPIO for details please see the relevant manuals.
Module supports a new key connection, can support 50 keys, which meets full keyboard demand, the connection
diagram is as following:
KBR4
KBR0
KBC0
KBC4
20K
Module
20K
Figure 38: 50 keys reference circuit
Note
:
Do not change the 20KΩ resistor in the diagram.
Customer could cascade a less than 1K resistor to enhance the ESD performance, the connection diagram is as
following:
SIMCOM
CONFIDENTIAL
FILE