Contents
What is RS232 level shifter?
The RS232 Level Shifter converts the Low- Voltage TTL voltage level supported on the serial interface of the SBC-AVL Power into V. 28 (12 Volt) voltage level as required for RS232 devices.
What are the RS232 voltage levels?
Table 1. RS-232 Specifications
| RS-232 | |
|---|---|
| Space (data 0) | 5V (min) 15V (max) |
| Input Level (min) | ±3V |
| Output Current | 500mA (Note that the driver ICs normally used in PCs are limited to 10mA) |
| Impedance | 5kΩ (Internal) |
What kind of interface is needed for RS232?
Serial port (DB9) is among the most popular interface between computer and devices such as GSM modem and RFID reader. However, since computer is using RS232 interface while microcontroller is using TTL UART interface, a level shifter is needed in order for the microcontroller to interface with the RS232 peripheral device.
Can a shifter SMD be used to convert RS232 to TTL?
This board has one purpose in life – to convert RS232 to TTL and vice versa (TX and RX). This will allow a microcontroller to communicate with a computer. Shifter SMD is powered from the target application and can run at any voltage! That’s right – power the board at 5V and the unit will convert RS232 to 5V TTL.
What kind of power does a SparkFun RS232 shifter need?
That’s right – power the board at 5V and the unit will convert RS232 to 5V TTL. Power the board at 2.8V and the Shifter board will convert RS232 to 2.8V CMOS TTL. Includes two indicator LEDs for TX and RX.
What should TTL signal be on SparkFun RS232?
We recommend using the RS232 Shifter running at 5V (or anything higher than 2.8V) for the TTL side and further convert the signal down to 1.8V with the TXB0104 [ https://www.sparkfun.com/products/11771 ]. The TXB0104 can translate down to 1.2V.