ADC081S021 Datasheet, PDF (5/17 Pages) National Semiconductor (TI) – Single Channel, 50 to 200ksps, 8-Bit A/D Converter

ADC081S021 Converter Electrical Characteristics (Notes 7, 9) (Continued)
The following specifications apply for V_A = +2.7V to 5.25V, f_SCLK = 1 MHz to 4 MHz, f_SAMPLE = 50 ksps to 200 ksps,
C_L = 15 pF, unless otherwise noted. Boldface limits apply for T_A = T_MIN to T_MAX: all other limits T_A = 25˚C.
Symbol
Parameter
Conditions
Typical
Limits
(Note 9)
Units
AC ELECTRICAL CHARACTERISTICS
f_S
Sample Rate
(Note 8)
50
ksps (min)
200
ksps (max)
t_CONV
DC
Conversion Time
SCLK Duty Cycle
f_SCLK = 4 MHz
16
SCLK cycles
40
% (min)
50
60
% (max)
t_ACQ
Track/Hold Acquisition Time
Throughput Time
Acquisition Time + Conversion Time
400
ns (max)
20
SCLK cycles
t_QUIET
t_AD
t_AJ
(Note 10)
Aperture Delay
Aperture Jitter
50
ns (min)
3
ns
30
ps
ADC081S021 Timing Specifications
The following specifications apply for V_A = +2.7V to 5.25V, GND = 0V, f_SCLK = 1.0 MHz to 4.0 MHz, C_L = 25 pF,
f_SAMPLE = 50 ksps to 200 ksps, Boldface limits apply for T_A = T_MIN to T_MAX: all other limits T_A = 25˚C.
Symbol
Parameter
Conditions
Typical
Limits
t_CS
Minimum CS Pulse Width
10
t_SU
CS to SCLK Setup Time
10
Delay from CS Until SDATA TRI-STATE^®
t_EN
Disabled (Note 11)
20
Data Access Time after SCLK Falling Edge
t_ACC
(Note 12)
t_CL
SCLK Low Pulse Width
t_CH
SCLK High Pulse Width
t_H
SCLK to Data Valid Hold Time
SCLK Falling Edge to SDATA High
t_DIS
Impedance (Note 13)
V_A = +2.7V to +3.6V
V_A = +4.75V to +5.25V
V_A = +2.7V to +3.6V
V_A = +4.75V to +5.25V
V_A = +2.7V to +3.6V
V_A = +4.75V to +5.25V
40
20
0.4 x
t_SCLK
0.4 x
t_SCLK
7
5
25
6
25
5
t_POWER-UP Power-Up Time from Full Power-Down
1
Units
ns (min)
ns (min)
ns (max)
ns (max)
ns (max)
ns (min)
ns (min)
ns (min)
ns (min)
ns (max)
ns (min)
ns (max)
ns (min)
µs
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed
specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test
conditions.
Note 2: All voltages are measured with respect to GND = 0V, unless otherwise specified.
Note 3: When the input voltage at any pin exceeds the power supply (that is, V_IN < GND or V_IN > V_A), the current at that pin should be limited to 10 mA. The 20
mA maximum package input current rating limits the number of pins that can safely exceed the power supplies with an input current of 10 mA to two. The Absolute
Maximum Rating specification does not apply to the V_A pin. The current into the V_A pin is limited by the Analog Supply Voltage specification.
Note 4: The absolute maximum junction temperature (T_Jmax) for this device is 150˚C. The maximum allowable power dissipation is dictated by T_Jmax, the
junction-to-ambient thermal resistance (θ_JA), and the ambient temperature (T_A), and can be calculated using the formula P_DMAX = (T_Jmax − T_A)/θ_JA. The values
for maximum power dissipation listed above will be reached only when the device is operated in a severe fault condition (e.g. when input or output pins are driven
beyond the power supply voltages, or the power supply polarity is reversed). Obviously, such conditions should always be avoided.
Note 5: Human body model is 100 pF capacitor discharged through a 1.5 kΩ resistor. Machine model is 220 pF discharged through zero ohms
Note 6: Reflow temperature profiles are different for lead-free and non-lead-free packages.
Note 7: Tested limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 8: This is the frequency range over which the electrical performance is guaranteed. The device is functional over a wider range which is specified under
Operating Ratings.
Note 9: Data sheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Note 10: Minimum Quiet Time required by bus relinquish and the start of the next conversion.
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