Linear Technology LTC2983 - Page 56

LTC2983
56
2983fc
For more information www.linear.com/LTC2983
SUPPLEMENTAL INFORMATION
The data is represented as a 32-bit word (see Table 63)
where the eight most significant bits are fault bits and the
bottom 24 are the ADC reading in volts. For direct ADC
readings hard fault errors do not clamp the digital output.
Readings beyond ±1.125 • V
REF
/2 exceed the normal ac-
curacy range of the LTC2983 and flag a soft error; these
results should be discarded. Readings beyond ±1.75 •
V
REF
/2 exceed the usable range of the LTC2983; these
result in a hard fault and should be discarded.
Figures 34 to 36 show typical integral nonlinearity varia-
tion at various supply voltages and temperatures for a
differential input voltage (±V
REF
/2) and V
REF
/2 common
mode input voltage.
Figure 34. Integral Nonlinearity as a Function of
Temperature at V
DD
= 5.25V
Figure 36. Integral Nonlinearity as a Function of
Temperature at V
DD
= 2.85V
Figure 35. Integral Nonlinearity as a Function of
Temperature at V
DD
= 3.3V
DIFFERENTIAL INPUT VOLTAGE (V)
INL ERROR (ppm)
2983 F34
20
15
10
5
0
–5
–10
–15
–20
–1.5 –0.5 0 0.5 1 1.5–1
90°C
25°C
–45°C
DIFFERENTIAL INPUT VOLTAGE (V)
INL ERROR (ppm)
2983 F35
20
15
10
5
0
–5
–10
–15
–20
–1.5 –0.5 0 0.5 1 1.5–1
90°C
25°C
–45°C
DIFFERENTIAL INPUT VOLTAGE (V)
INL ERROR (ppm)
2983 F36
20
15
10
5
0
–5
–10
–15
–20
–1.5 –0.5 0 0.5 1 1.5–1
90°C
25°C
–45°C