101-1006 Rabbit Semiconductor, 101-1006 Datasheet - Page 46

• 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

4.4 Ramp Generator
The PowerCore module has an onboard ramp generator that provides a a continuous
sawtooth function with a precision rising ramp. The calibration of the ramp is tied to an
onboard 2.5 V voltage reference. The 400 Hz ramp has a linear rise time from 0 to 3.1 V of
approximately 1.9 ms, and ramps down in approximately 0.45 ms. (The ramp actually
starts at a slightly negative voltage of approximately -0.05 V.) The ramp output has a
linearity of about 0.1% and is available for external circuits on pin 50 of header J4.
Figure 9. PowerCore Ramp Generator Signal
The onboard 2.5 V reference circuit is shown in Figure 10.
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Figure 10. Onboard 2.5 V Reference
The ramp generator makes it possible to measure analog voltages using LM339 compara-
tors and the pulse capture capabilities of the Rabbit 3000 microprocessor to convert time
into voltage. One example of this analog measurement capability is the onboard ther-
mistor, which allows temperature measurements of the PowerCore circuit board.
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PowerCore FLEX