adc0804-mdc National Semiconductor Corporation, adc0804-mdc Datasheet - Page 16

• Manufacturer Part Number: adc0804-mdc
• Description: 8-bit Up Compatible A/d Converters
• Manufacturer: National Semiconductor Corporation

www.national.com
Typical Applications
Note 11: Oversample whenever possible [keep fs
Note 12: Consider the amplitude errors which are introduced within the passband of the filter.
(Complete shutdown takes
*Use ADC0801, 02, 03 or 05 for lowest power consumption.
Note: Logic inputs can be driven to V
Buffer prevents data bus from overdriving output of A/D when in shutdown mode.
Functional Description
1.0 UNDERSTANDING A/D ERROR SPECS
A perfect A/D transfer characteristic (staircase waveform) is
shown in Figure 1 . The horizontal scale is analog input
voltage and the particular points labeled are in steps of 1
LSB (19.53 mV with 2.5V tied to the V
output codes that correspond to these inputs are shown as
30 seconds.)
CC
with A/D supply at zero volts.
(Continued)
REF
>
Power Savings by A/D and V
/2 pin). The digital
2f(−60)] to eliminate input frequency folding (aliasing) and to allow for the skirt response of the filter.
70% Power Savings by Clock Gating
Sampling an AC Input Signal
16
D−1, D, and D+1. For the perfect A/D, not only will
center-value (A−1, A, A+1, . . . . ) analog inputs produce
the correct output digital codes, but also each riser (the
transitions between adjacent output codes) will be located
±
are ideal and have no width. Correct digital output codes will
be provided for a range of analog input voltages that extend
1
⁄
2
REF
LSB away from each center-value. As shown, the risers
Shutdown
DS005671-78
DS005671-79
DS005671-80