Speakerguy
Active Member
I have a grounded oscilloscope (Tek DPO3k series) and I will shortly be working with a full-bridge audio PWM amplifier chip (TI TAS5261). I know I cannot use my regular grounded probe and grounded scope with a regular power supply where it's GND is tied to neutral (as it should be in safely earthed amplifiers).
I need a solution so that I can look at the output of the H-bridge PWM amp section. A Tek probe is prohibitively expensive. Are there other brands of probes that would be OK? Can I use a 3 to 2 cheater plug to lift the scope ground? Or would I still have a problem?
I will be using an isolated switching supply (24V 320W) for the power amp output section, but it's (V-) may be connected to say the USB ground or some other ground that is earthed, and I don't want to count on everything being isolated from ground/neutral so that I could use my earthed scope.
Would an isolation transformer fix my problem, or do I need to find a differential probe? The Tek active probe is four figures! and I don't want to spend that. Need it to be 100MHz, would prefer 300-500MHz (scope is 300MHz).
I need a solution so that I can look at the output of the H-bridge PWM amp section. A Tek probe is prohibitively expensive. Are there other brands of probes that would be OK? Can I use a 3 to 2 cheater plug to lift the scope ground? Or would I still have a problem?
I will be using an isolated switching supply (24V 320W) for the power amp output section, but it's (V-) may be connected to say the USB ground or some other ground that is earthed, and I don't want to count on everything being isolated from ground/neutral so that I could use my earthed scope.
Would an isolation transformer fix my problem, or do I need to find a differential probe? The Tek active probe is four figures! and I don't want to spend that. Need it to be 100MHz, would prefer 300-500MHz (scope is 300MHz).