Datasheet

ADAS3022 Data Sheet
Rev. B | Page 24 of 40
Table 6. Output Codes and Ideal Input Voltages
Description
Differential Analog
Inputs, V
REF
= 4.096 V
Digital Output Code
(Twos Complement, Hex)
FSR − 1 LSB
(32,767 × V
REF
)/
(32,768 × PGIA gain)
0x7FFF
Midscale + 1 LSB
V
REF
/(32,768 × PGIA
gain)
0x0001
Midscale 0 0x0000
Midscale − 1 LSB
−(V
REF
/(32,768 × PGIA
gain))
0xFFFF
−FSR + 1 LSB
−(32,767 × V
REF
)/
(32,768 × PGIA gain)
0x8001
−FSR −V
REF
× PGIA gain 0x8000
TYPICAL APPLICATION CONNECTION DIAGRAM
As shown in Figure 54, the ADP1613 is used in an inexpensive
SEPIC-Ćuk topology, which is an ideal candidate for providing
the ADAS3022 with the necessary high voltage ±15 V robust
supplies (at 20 mA) and low output ripple (3 mV maximum)
from an external 5 V supply. The ADP1613 satisfies the
specification requirements of the ADAS3022 with minimal
external components while achieving greater than 86% of
efficiency. Refer to the CN-0201 circuit note for complete
information about this test setup.
IN0
IN0/IN1
IN2/IN3
IN4/IN5
IN6/IN7
IN1
IN2
IN3
IN4
IN5
IN6
IN7
DIFF
PAIR
DIFF
COM
LOGIC/
INTERFACE
REFIN
REF
MUX
CNV
RESET
SCK
DIN
SDO
VDDH AVDD DVDD VIO
CS
COM
AUX+
AUX–
BUSY
+
+
+
ENABLE
ADP1613
ADAS3022
COMP
FB FREQ
EN VIN
GND
SS
SW
+
+
V
IN
= +5V
+
+
+
+
VSSH
RF2
4.22kΩ
RF1B
47.5kΩ
R
C
1
100kΩ
C
C
1
12nF
C
C
2
10pF
C
V
5
1µF
R
EN
R
B
0
1Ω
R
S
1
0Ω
R
S
2
DNI
C
SS
1µF
Z1
C
IN
1µF
D1
D2
C1
1µF
C2
1µF
L3
1µF
C
OUT
3
4.7µF
C
OUT
1
1µF
C
OUT
2
2.2µF
+15V
–15V
+5V
ADR434
REFx
PD
AGND DGND
AD8031
4.096V
+
–
1.78Ω
R
FILT
DNI
50kΩ
L1
47µH
L2
47µH
+
+5V
+5V
BUF
PulSAR
ADC
10516-200
TEMP
SENSOR
PGIA
Figure 54. Complete 5 V, Single-Supply, 8-Channel Multiplexed Data Acquisition System with PGIA