Manual CH330 (Nanjing Qinheng Microelectronics) - 2

CH330 manual 2 Power supply, the operating voltage and the other circuit connected CH330 not exceed 3.3V. CH330 allows the serial baud rate error of the received signal is not less than 2%, the baud rate of the serial signal transmission error is less than 1.2%. 6, parameters 6.1. Absolute maximum (equal to or exceed absolute maximum value will likely cause the chip does not work properly or even damage) name Parameter Description Minimum Maximum Unit TA Ambient temperature at work --20 70 ℃ TS The ambient temperature during storage - 55 100 ℃ VCC Supply voltage (VCC power supply connected, GND Ground) - 0.5 6.0 V VIO Voltage on the input or output pins - 0.5 VCC + 0.5 V 6.2 Electrical parameters (test conditions: TA = 25 ℃, VCC = 5V, does not include USB bus connector pin) name Parameter Description Min Typ Max Units V3 pin VCC pin is not connected 4.2 5 5.3 VCC voltage V V3 connect the VCC pin 3.1 3.3 3.5 VCC = 5V 7 15 mA ICC Work total supply current VCC = 3.3V 5 12 mA VIL Low level input voltage - 0.5 0.7 V VIH High-level input voltage 2.0 VCC + 0.5 V VOL Low-level output voltage (6mA current sinking) 0.5 V VOH High level output voltage (output current 4mA) VCC-0.5 V IUP Input current on-chip pull-up resistor input terminal 20 150 300 uA 7, USB to RS232 serial port application The figure is USB to RS232 serial port by CH330. Level converting circuit U5 (MAX232 / ICL232 / SP232 etc.) for converting the TTL to RS232 serial port. If only USB to serial TTL, then U5 may be removed and the capacitor of FIG C25 / C26 / C27 / C28 / C29. P1 is the USB port. If the low-power chip and CH330 USB 5V supply products directly by USB bus, may be replaced in FIG protection resistor R1 or short.
If the USB products provided by other common power supply, then CH330 should use the common power, FIG R1 may be disconnected, and both directly connected to the ground line.
The capacity of the capacitor C2 V3 pin is 0.1μF, 3.3V for the internal power supply node CH330 decoupling, C1 capacity of 0.1μF, an external power supply decoupling. Decoupling capacitors C1 and C2 should be connected as close as possible CH330 pin. Document Outline 1、概述 2、特点 3、封装 4、引脚 5、功能说明 6、参数 6.1. 绝对最大值 6.2. 电气参数 7、USB转RS232串口应用 8、连接单片机串口，各自供电