acpl-c797 Avago Technologies, acpl-c797 Datasheet - Page 9

• Manufacturer Part Number: acpl-c797
• Description: Optically Isolated Sigma-delta Modulator
• Manufacturer: Avago Technologies

Figure 11. I
Figure 13.Clock frequency vs. temperature for various V
Definitions
Integral Nonlinearity (INL)
INL is the maximum deviation of a transfer curve from a
straight line passing through the endpoints of the ADC
transfer function, with offset and gain errors adjusted out.
Differential Nonlinearity (DNL)
DNL is the deviation of an actual code width from the
ideal value of 1 LSB between any two adjacent codes in
the ADC transfer curve. DNL is a critical specification in
closed-loop applications. A DNL error of less than ±1 LSB
guarantees no missing codes and a monotonic transfer
function.
Offset Error
Offset error is the deviation of the actual input voltage
corresponding to the mid-scale code (32,768 for a 16-bit
system with an unsigned decimation filter) from 0 V. Offset
error can be corrected by software or hardware.
9
8.0
7.0
6.0
5.0
4.0
3.0
2.0
10.5
10.4
10.3
10.2
10.1
10.0
9.9
9.8
9.7
9.6
9.5
-400
-55
DD2
-300
(V
-35
DD2
= 5 V) vs. V
-15
-200
5
-100
IN
Temperature (°C)
DC input at various temperatures
V
25
IN
(mV)
0
45
100
65
200
DD1
85
300
25° C
-40° C
105° C
105
4.5V
5V
5.5V
400
125
Figure 12. I
Gain Error (Full-Scale Error)
Gain error includes positive full-scale gain error and
negative full-scale gain error. Positive full-scale gain error
is the deviation of the actual input voltage correspond-
ing to positive full-scale code (65,535 for a 16-bit system)
from the ideal differential input voltage (V
+320 mV), with offset error adjusted out. Negative full-
scale gain error is the deviation of the actual input voltage
corresponding to negative full-scale code (0 for a 16-bit
system) from the ideal differential input voltage (V
V
includes reference error. Gain error can be corrected by
software or hardware.
Signal-to-Noise Ratio (SNR)
The SNR is the measured ratio of AC signal power to noise
power below half of the sampling frequency. The noise
power excludes harmonic signals and DC.
IN
8.0
7.0
6.0
5.0
4.0
3.0
2.0
– = –320 mV), with offset error adjusted out. Gain error
-400
V
DD2
DD2
-300
(V
= 3.3 V
DD2
= 3.3 V) vs. V
-200
-100
IN
DC input at various temperatures
V
IN
0
(mV)
100
200
IN
300
+ – V
25° C
-40° C
105° C
400
IN
IN
– =
+ –