Scope probe options add power-system-monitoring functions

December 02, 2016 // By Graham Prophet
LeCroy’s RP4030 active voltage rail probe and SPMI decoder adds measurement functions to the company’s 8-channel & 4-GHz high definition oscilloscopes for digital power management IC (PMIC), power sequencing, and power-integrity testing.

The RP4030 active voltage rail probe measures small signal variations on a DC power/voltage rail and, claimed as an industry first, the MIPI System Power Management Interface (SPMI) serial decoder monitors and correlates SPMI serial bus messages with DC power/voltage rail changes. These two products are intended for testing line or battery-powered computing and embedded systems that use digital power management ICs (PMICs) to reduce power consumption and increase system efficiency.


The RP4030 has a large (±30V) built-in offset range, low attenuation (1.2x), and high DC input impedance (50 kΩ). This combination of capabilities permits acquisition of DC power/voltage rails with offset equal to the nominal DC rail voltage thereby permitting the DC signal to be centered on the oscilloscope screen and the use of high-sensitivity oscilloscope gain settings (e.g. 5 mV/div) to view the noise and small signal AC variations on the DC rail voltage. The probe has 4 GHz of bandwidth and matches the Teledyne LeCroy HDO9404 High Definition Oscilloscope for power-integrity testing. It comes with a wide combination of tips and leads.


Developers of mobile/handheld and battery-powered systems often turn to the MIPI SPMI to facilitate communication between embedded system CPUs and power management ICs (PMICs). The goal is to maintain desired system performance while adjusting power levels to achieve the best embedded system efficiencies. Teledyne LeCroy’s SPMI decoder provides an intuitive, transparent, colour-coded protocol decode overlay for the acquired SPMI physical-layer waveform. The SPMI protocol decode information is also displayed in a single time-interleaved table with other protocol data. Touching a row in the interactive table quickly zooms to the selected protocol packet, and pattern searches and filters provide an easy means of locating the desired protocol packets and messages. The SPMI decoder is multi-master/multi-slave capable, provides full command and arbitration sequence support, and supports all sequences with pauses.


Teledyne LeCroy is also announcing “Alpha” availability of an Advanced Rail Analysis Toolbox. This