Do analog multimeters work the same as digital multimeters?
Different.
The internal structure of the analog multimeter includes a meter head, a resistor, and a battery, and the meter head generally adopts a magnetoelectric DC microammeter. Only use its internal battery when measuring resistance, the positive electrode of the battery is connected to the black test lead, so the current flows out from the black test lead, and the red test lead flows in. When measuring DC current, shunt the current by connecting parallel resistors by shifting gears. Because the full-bias current of the meter head is very small, the shunt resistors are used to expand the range. When measuring DC voltage, connect resistors in series on the meter head, and realize the conversion of different ranges through different additional resistors.
A digital multimeter is composed of a function converter, an A/D converter, an LCD display (liquid crystal display), a power supply, and a function/range conversion switch, among which the A/D converter generally uses the ICL7106 dual-integral A/D converter . The ICL7106 uses two integrations, the first integration of the input analog signal V1 is called the sampling process; the second integration of the reference voltage - VEF is called the comparison process. The two integration processes are counted by a binary counter, converted into digital quantities, and displayed in digital form. To measure electricity such as AC voltage, current, resistance, capacitance, diode forward voltage drop, and transistor amplification factor, a corresponding converter must be added to convert the measured electricity into a DC voltage signal. Note that the positive pole of the digital multimeter corresponds to the red test lead, not the black test lead.
