Product Features:

Using PL2303TA (compatible with PL2303HXA)
Support windows XP/7/8/8.1/10/...
Supports 3 power modes: 5V external power supply; 3.3V external power supply; external power supply (3.3V-5V required)
With 3 LEDs: TXD LED, RXD LED, POWER LED
Instructions for use: (take access MCU as an example)

VCCIO: Output 3.3V or 5V (The module is powered by USB and the jumper must jump to 3.3V or 5V)
GND: Connect to GND
TXD: Connect to MCU.RX (Signal flow: MCU.RX << PL2303 << PC.TX)
RXD: Connect to MCU.TX (Signal Flow: MCU.TX >> PL2303 >> PC.RX)
Note: This module is USB to TTL level, do not connect directly to RS232 level, so as not to burn out the module.