z8f1621 ZiLOG Semiconductor, z8f1621 Datasheet - Page 186

• Manufacturer Part Number: z8f1621
• Description: High Performance 8-bit Microcontrollers
• Manufacturer: ZiLOG Semiconductor

Operation
PS019921-0308
Automatic Power-Down
The sigma-delta ADC architecture provides alias and image attenuation below the ampli-
tude resolution of the ADC in the frequency range of DC to one-half the ADC clock rate
(one-fourth the system clock rate). The ADC provides alias free conversion for frequen-
cies up to one-half the ADC clock rate. Thus the sigma-delta ADC exhibits high noise
immunity making it ideal for embedded applications. In addition, monotonicity (no miss-
ing codes) is guaranteed by design.
If the ADC is idle (no conversions in progress) for 160 consecutive system clock cycles,
portions of the ADC are automatically powered-down. From this power-down state, the
ADC requires 40 system clock cycles to power-up. The ADC powers up when a conver-
sion is requested using the ADC Control register.
Reference Generator
Analog-to-Digital
Internal Voltage
Figure 33. Analog-to-Digital Converter Block Diagram
Reference Input
Converter
Analog Input
Analog Input
ANAIN[3:0]
Multiplexer
Z8 Encore! XP
Product Specification
Analog-to-Digital Converter
ANA0
ANA1
ANA2
ANA3
ANA4
ANA5
ANA6
ANA7
ANA8
ANA9
ANA10
ANA11
VREF
®
F64XX Series
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