COP87L88GD Datasheet, PDF (6/39 Pages) National Semiconductor (TI) – 8-Bit CMOS OTP Microcontrollers with 16k or 32k Memory and 8-Channel A/D with Prescaler

A/D Converter Specifications
V_CC = 5V ±10%, (V_SS–0.050V) ≤ Any Input ≤ (V_CC + 0.050V)
Parameter
Conditions
Resolution
Absolute Accuracy
Non-Linearity
Deviation from the Best Straight Line
Differential Non-Linearity
Common Mode Input Range (Note 12)
DC Common Mode Error
Off Channel Leakage Current
On Channel Leakage Current
A/D Clock Frequency (Note 11)
Converison Time (Note 10)
Internal Reference Resistance
Tum-on Time (Note 13)
Min Typ Max
8
±2
±1
±1
GND
V_CC
±1/2
1
2
1
2
0.1
1.67
17
1
Units
Bits
LSB
LSB
LSB
V
LSB
µA
µA
MHz
A/D Clock Cycles
µs
Note 10: Conversion Time includes 7 A/D clock cycles sample and hold time.
Note 11: See Prescaler description.
Note 12: For V_IN(−) > = V_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 ana-
log input voltages below ground or above the V_CC supply. Be careful, during testing at low V_CC levels (4.5V), as high level analog inputs (5V) can cause this input
diode 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_IN does not exceed the supply voltage by more than 50 mV, the output code will be correct. To achieve an absolute 0 V_DC to 5
V_DC input voltage range will therefore require a minimum supply voltage of 4.950 V_DC over temperature variations, initial tolerance and loading.
Note 13: Time or internal reference reistance to turn on and settle after coming out of HALT or IDLE mode.
DS012526-4
FIGURE 3. MICROWIRE/PLUS Timing
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