| 摘要 |
An auto-gain control circuit of an infrared receiver is provided to prevent a gain control voltage from being changed abnormally by having a buffer unit of a voltage-current conversion unit. An auto-gain control circuit of an infrared receiver includes a gain amplifying unit(200), an auto-gain control unit(210), a charging/discharging unit(220), and a voltage-current conversion unit(230). The gain amplifying unit amplifies an input signal in response to a gain control current. The auto-gain control unit compares an output of the gain amplifying unit with a reference voltage, and outputs a charging control signal or a discharging control signal. The charging/discharging unit generates a gain control voltage by performing a charging/discharging operation in response to the charging control signal or the discharging control signal. The voltage-current conversion unit converts the gain control voltage of the charging/discharging unit into a gain control current. The voltage-current conversion unit cuts off a leakage current using MOS transistors, buffers the gain control voltage, and converts the gain control voltage into the gain control current. |
