User's Manual
Table Of Contents
- 1.Introduction
- 2.Package Information
- 3.Interface Application
- 4.RF Specifications
- 5.Electrical Specifications
- 6.SMT Production Guide
- 7.Packaging
- 8.Appendix
SIM7075G User Manual V1.00
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Figure 12: UART null modem
Table 12: UART electronic characteristic
Symbol
Description
Min.
Typ.
Max.
Unit
VIH
UART input high level voltage
1.17
1.8
2.1
V
VIL
UART input low level voltage
-0.3
0
0.63
V
VOH
UART output high level voltage
1.35
1.8
1.8
V
VOL
UART output low level voltage
0
0
0.45
V
The SIM7075G UART is 1.8V voltage interface. If user
’
s UART application circuit is 3.3V voltage interface,
the level shifter circuits should be used for voltage matching. The following figure shows the voltage
matching reference design.
Figure 13: Reference circuit with level shifter IC