Analogue Signal Monitor Interface (ASM)
The analogue signal monitor interface is based on differential receiver circuit where both the high and low analogue signal lines are floating with respect to the receiver signal ground; the source interface can be either single ended or differential. The analogue voltage provided is sampled intermittently by the core element. The precise frequency and the duration of the sampling interval depend on the A/D conversion service being used. However, the input impedance and capacitance exhibited by an analogue signal interface can differ when the input signal is actually being sampled compared with when it is not. As a consequence, different input impedance and capacitance requirements are provided for the different configurations. In addition, the impedance seen when the receiver element is powered off is specified. Figures 2 show electrical arrangements, which show specific implementation of the ASM for single ended source and differential ended source respectively. Of course, other implementations which are compliant with the requirements are not excluded.
Last update: 21 March 2012