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UCC27525: Excessive and systematic cycle to cycle jitter repeating every other cycle

Part Number: UCC27525

I am experiencing excessive output jitter from a UCC27525D dual MOSFET driver:

I have built a test circuit to explore this problem in its most basic form and it would appear that it is attributable to unexpected operation of the device itself.

The test circuit I used to examine this consists of a UCC27525D supplied from a 13V bench supply and with 10nF, 100nF and 10uF parallel power supply decoupling capacitors in close proximity to the device power pins and with good connections directly to the device ground/power pins (pin 3 and pin 6 respectively). A 3V square wave is injected into the non-inverting driver input pin (pin 4) via a short coaxial cable terminated in 51R directly at the test device. The input (pin 4) and output (pin 5) are monitored using a high-performance 1GHz bandwitdth oscilloscope (Agilent 9000 series) with locally earthed oscilloscope probes. The enables (pin 1 & pin 8) and unused inverting input (pin 2) to the device are left open circuit. There is no load other than the oscilloscope probe on the output being monitored.

The oscilloscope screen shots below were captured with colour grade enabled on the oscilloscope. This clearly shows a quantised varying delay (jitter) on both rising and falling output edges with respect to the associated input transition. These delays alternate each cycle between the two discrete delays.

It should be noted that this jitter effect starts to occur for input waveforms exceeding approximately 1MHz and varies in magnitude with the frequency of the input waveform.

TOP Trace = Input (Pin 4), BOTTOM Trace = Output (pin 5)

Any advice you can give to help resolve this problem would be very much appreciated.