cop888cf National Semiconductor Corporation, cop888cf Datasheet - Page 11

• Manufacturer Part Number: cop888cf
• Description: 8-bit Cmos Rom Based Microcontrollers With 4k Memory And A/d Converter
• Manufacturer: National Semiconductor Corporation

A/D Converter Specifications
Note 17: Pins G6 and RESET are designed with a high voltage input network for factory testing. These pins allow input voltages greater than V
have sink current to V
tance to V
Note 18: For V
input voltages below ground or above the V
to conduct — especially at elevated temperatures, and cause errors for analog inputs near full-scale. The spec allows 50 mV forward bias of either diode. This means
that as long as the analog V
voltage range will therefore require a minimum supply voltage of 4.950 V
should be −0.3V to V
CC
is 750
IN
(−) V
CC
CC
(typical). These two pins will not latch up. The voltage at the pins must be limited to less than 14V.
IN
(+) the digital output code will be 0000 0000. Two on-chip diodes are tied to each analog input. The diodes will forward conduct for analog
+0.3V.
when biased at voltages greater than V
IN
does not exceed the supply voltage by more than 50 mV, the output code will be correct. To achieve an absolute 0 V
CC
supply. Be careful, during testing at low V
FIGURE 3. MICROWIRE/PLUS Timing
(Continued)
CC
(the pins do not have source current when biased at a voltage below V
DC
over temperature variations, initial tolerance and loading. The voltage on any analog input
11
CC
levels (4.5V), as high level analog inputs (5V) can cause this input diode
DS009425-26
CC
). The effective resis-
CC
DC
and the pins will
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to 5 V
DC
input