What is the reason why the digital multimeter will shut down when it is in the peak tone mode
It is not ruled out that the battery is running out of power. When using the buzzer mode, the buzzer is an inductive load, and the instantaneous voltage may be relatively large, which may pull down the battery with little power, causing the main chip to shut down directly due to insufficient voltage.
If the battery is still the same, it may be caused by the short circuit of the buzzer or the related drive circuit and the leakage of electricity. There is no need to worry about it. A multimeter does not cost much, and it takes more time.
Or try simply replacing a buzzer, if it doesn't work, just buy a new one.
There are generally two situations where the digital multimeter automatically shuts down when using the buzzer gear. One is that the battery of the multimeter is old, and the battery voltage is significantly reduced when the buzzer gear that consumes a lot of power is working, so that the multimeter automatically shuts down; Another situation is that the buzzer file is faulty, and the current of this file is very large when it is working, which causes the battery voltage to drop significantly, thus causing the multimeter to shut down. Let's introduce the working principle of the circuit of the digital multimeter buzzer file and the maintenance of the fault in more detail.
The operating current of other gears of general digital multimeters is mostly within 10mA, and the buzzer gear consumes a lot of power due to piezoelectric ceramics and indicator lights (relatively speaking), if the battery of the multimeter is old, it may be at this time. This causes the battery voltage to drop significantly, causing the multimeter to shut down.
In addition, if the CMOS gate circuit CD4011 of the buzzer gear or the piezoelectric ceramic chip fails, the power consumption of the entire buzzer gear will increase significantly, and the multimeter will automatically shut down at this time. The author has previously repaired the fault of high power consumption of the buzzer gear, mostly caused by CD4011 or piezoelectric ceramic chips. Generally, when there is a slight short circuit at both ends of the piezoelectric ceramic sheet, the sound of the buzzer gear will decrease and the power consumption will increase.
