Datasheet

LTC1863/LTC1867
14
18637fa
Figure 7. Example 2, CS/CONV Starts a Conversion With Short Active HIGH Pulse.
With CS/CONV Returning LOW Before the Conversion, the ADC Remains Powered Up.
INPUT VOLTAGE (V)
OUTPUT CODE
1867 F09
111...111
111...110
100...001
100...000
000...000
000...001
011...110
011...111
FS – 1LSB0V
UNIPOLAR
ZERO
FS = 4.096
1LSB = FS/2
n
1LSB = (LTC1863) = 1mV
1LSB = (LTC1867) = 62.5μV
Figure 8. LTC1863/LTC1867 Bipolar Transfer
Characteristics (Two’s Complement)
Figure 9. LTC1863/LTC1867 Unipolar Transfer
Characteristics (Straight Binary)
S0SD 0S S1 COM UNI SLP
MSB = D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
CS/CONV
SCK
SDI
SDO
(LTC1867)
Hi-Z
12345678910111213141516
t
CONV
D12MSB = D15 D14 D13 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
Hi-Z
1867 F07
t
CONV
DON'T CAREDON'T CARE
NOT NEEDED FOR LTC1863
t
ACQ
SDO
(LTC1863)
DON'T CARE
INPUT VOLTAGE (V)
0V
OUTPUT CODE (TWO’S COMPLIMENT)
–1
LSB
1867 F08
011...111
011...110
000...001
000...000
100...000
100...001
111...110
1
LSB
BIPOLAR
ZERO
111...111
FS/2 – 1LSB–FS/2
FS = 4.096
1LSB = FS/2
n
1LSB = (LTC1863) = 1mV
1LSB = (LTC1867) = 62.5μV
APPLICATIONS INFORMATION