AN2688 Freescale Semiconductor / Motorola, AN2688 Datasheet - Page 5

• Manufacturer Part Number: AN2688
• Description: Implementing a 10-Bit Sigma-Delta Analog-to-Digital Converter Using the HC9S08Rx MCU Family Analog Comparator
• Manufacturer: Freescale Semiconductor / Motorola

First Order Continuous-Time Σ∆ AD Converter Characteristics
HC9S08Rx Features and Benefits
MOTOROLA
Σ∆ AD converter characteristics include:
Standard features of the HCS08 Family
Features of the MC9S08RC/RD/RE/RG MCU Family
Implementing a 10-Bit Sigma-Delta Analog-to-Digital Converter
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Using the HC9S08Rx MCU Family Analog Comparator
Low cost implementation with few external components
Low complexity especially in the analog domain since the HC9S08Rx MCU
itself provides the digital processing capacity needed
Small amount of memory required
Input range controlled by external resistors
Low matching level in between external components
Performance immunity face-to-comparator hysteresis
Modulator highly robust and inherently stable
Accurate internal bandgap reference voltage
Converter inherently linear and inherently monotonic
Very simple anti-alias low-pass filter feasible to embed with the RC passive
integrator
Sample and hold, and trimming circuitry not required
Architecture not particularly appropriate for DC inputs but for busy signals
DC input applications require radiometric measurements and dithering
61.2 dB of SNR equivalent to 10-bits resolution
65.7 dB of dynamic range (DR) at 2.4 V of power supply
Extended battery life technology
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High-performance when needed
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Innovative on-chip trigger/trace debug capability
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8 MHz internal bus frequency
On-chip in-circuit programmable FLASH memory with block protection and
security option
On-chip random-access memory (RAM)
Freescale Semiconductor, Inc.
For More Information On This Product,
Multiple power management modes including 20 nA power down @ 2 V
Optional auto wake-up with internal timer and internal oscillator typically
700 nA @ 2 V
1.8–3.6 V operation
125 ns minimum instruction cycle time down to 1.8 V @ 8 MHz bus
Single wire background debug mode
Trace capability with 9 trigger modes and 3 breakpoints
Go to: www.freescale.com
First Order Continuous-Time SD AD Converter Characteristics
AN2688/D
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