User's Manual
Table Of Contents
- Revision History
- Introduction
- Package Information
- Interface Application
- RF Specifications
- Electrical Specifications
- SMT Production Guide
- Packaging
- Appendix
Smart Machine Smart Decision
SIM7500A_User Manual_V1.022016-09-29
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Figure 12: UART full modem
Figure 13: UART null Modem
The Module UART is 1.8V voltage interface. If user’s UART application circuit is a 3.3V voltage
interface, the level shifter circuits should be used for voltage matching. The TXB0108RGYR
provided by Texas Instruments is recommended. The following figure shows the voltage matching
reference design.
Figure 14: Reference circuit of level shift
To comply with RS-232-C protocol, the RS-232-C level shifter chip should be used to connect
Module to the RS-232-C interface, for example SP3238ECA, etc.
Note: Module supports the following baud rates: 300, 600, 1200, 2400, 4800, 9600, 19200, 38400,
57600, 115200, 230400, 460800, 921600, 3200000, 3686400, 4000000bps. The default band rate
is 115200bps.