| 摘要 |
PURPOSE: A circuit for testing an X-ray protecting circuit of a monitor is provided to turn on a key switch mounted on an outer side of the monitor to input a key signal in a micro controller unit(MCU), without using a test jig, and to short a specific resistor of a voltage distributor to apply a pulse sensing voltage over a regular value to a high-voltage sensing circuit, so as to test whether the X-ray protecting circuit is normally operated. CONSTITUTION: A collector and an emitter of an X-ray test transistor(Q1) are connected with both terminals of voltage distributing resistors(R1,R3) of a voltage distributor(40). If a predetermined key signal is inputted when a key switch mounted on an outer side of a monitor is turned on, a micro controller unit(MCU)(60) applies a high signal to a base of the X-ray test transistor(Q1), to short the collector and the emitter of the X-ray test transistor(Q1). The MCU(60) generates a pulse sensing voltage(V2) over a standard value applied to a high-voltage sensing circuit(50), so that a user can decide whether an X-ray protecting circuit is normally operated.
|
