AN1740 Freescale Semiconductor / Motorola, AN1740 Datasheet - Page 46

• Manufacturer Part Number: AN1740
• Description: Applications Using the Analog Subsystem on MC68HC05JJ/JP Series Microcontrollers
• Manufacturer: Freescale Semiconductor / Motorola

Application Note
46
The advantages of this design are:
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Freescale Semiconductor, Inc.
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V
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CAP
For More Information On This Product,
Simple construction
Minimal on-chip silicon compared to most 8-bit successive
approximation register (SAR) A/D designs
More flexible than an SAR A/D, which must always perform as an
A/D and require its own D/A conversion circuitry
Some “filtering” of input signal provided by the integration
Inherently monotonic
Up to 16 bits are possible with long conversion times
CMP2
CPF2
CHG
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CAP
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PB0
AN0
PBX
CHARGE (CHG = 1)
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Figure 20. Single Slope A/D Convertor
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CHARGE
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CMP2
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SS
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CAP
DISCHARGE (CHG = 0)
PBX
PB0
AN0
DISCHARGE
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DISCHG
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MOTOROLA
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ON
CMP2
AN1740