Channel-isolated handheld digital oscillograph

Abstract

The invention discloses a channel-isolated handheld digital oscillograph. The handheld type digital oscillograph is divided into two separate signal conditioning, conversion and waveform data acquisition channels; a trigger synchronous signal isolation interface is used to realize the transmission of a trigger signal between two isolated channels; and a main control panel realizes control and data communication through USB isolated interfaces in the two isolated channels and supplies power for the two isolated channels through an isolation power supply; therefore, the oscillograph realizes the measuring function of a common handheld digital oscillograph and realizes electric isolation among two channels and the main control panel; and reference grounds of the two channels are separated with each other, and no short circuit occurs in testing.

Description

technical field [0001] The invention relates to the technical field of hand-held digital oscilloscopes, in particular to a channel-isolated hand-held digital oscilloscope. Background technique [0002] In many design, installation, and commissioning tasks, some operating parameters of the system are required to be tested in detail, such as motor drives, uninterruptible power supplies, power semiconductors, and other electronic equipment, which require detailed verification of switching losses, power waveforms, pulse waveforms, and harmonic components. wait. This type of circuit generally carries high voltage and high current, and the "reference ground" of each electronic component is inconsistent, and there may be a certain voltage difference. At this time, direct measurement with an ordinary digital oscilloscope without channel isolation is very easy to cause a short circuit, and even burn the device in severe cases. [0003] Common handheld digital oscilloscopes of the p...

AI Technical Summary

Problems solved by technology

[0008] from figure 2 , it can be seen that this type of ordinary handheld digital oscilloscope in the prior art is characterized by the "common ground" of each part, that is, the entire handheld digital oscilloscope system has only one "reference ground" GND, which limits this type of digital oscilloscope to a certain extent. Handheld Applications

For example, some systems under test have two reference points GND_A and GND_B, and there is a voltage difference between these two reference points. If these two reference points are connected to the "reference ground" of the first channel of the handheld digital oscilloscope and the The "reference ground" will lead to a short circuit between GND_A and GND_B, resulting in danger

[0009] In the existing technology, to solve the problem that the "reference ground" is inconsistent and the potential difference is easy to cause a short circuit, the usual method is to use a certain isolation sensing device or a special differential probe for testing, which increases the complexity of the test. It is very inconvenient; at the same time, it is also easy to operate by mistake, resulting in dangerous short circuit

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