101-1006 Rabbit Semiconductor, 101-1006 Datasheet - Page 47

• Manufacturer Part Number: 101-1006
• Description: MODULE POWERCORE FLEX 3800
• Manufacturer: Rabbit Semiconductor

Specifications of 101-1006

• Module/board Type: MPU Core Module
• For Use With/related Products: RCM3800
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

A similar, more general A/D measurement circuit can be designed. An example is the A/D
measurement circuit on the PowerCore Prototyping Board, which is shown in Figure 12.
The circuit is designed to accept input voltages of 0–10 V.
An A/D converter measurement is implemented when a signal transition from the compara-
tor is routed to an input capture on the Rabbit 3000 (for example, PD3 for the temperature-
measurement circuit and PG5 for the A/D measurement circuit on the Prototyping Board).
The counter in the Rabbit 3000 starts counting at the beginning of the ramp (PG1), and
stops when the ramp crosses the input signal (PG5). The full scale is approximately 4095
counts, which yields a measurement resolution of 12 bits. The end of the ramp activates an
interrupt to the Rabbit 3000, which then retrieves the count and stores it so that it can be
accessed by a software function call. Generally, additional channels will be measured in
User’s Manual
Figure 12. PowerCore Prototyping Board A/D Acquisition Circuit
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Figure 11. PowerCore Temperature-Measurement Circuit
thermistor
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