ꢋꢑ ꢉꢀ ꢁ ꢗ ꢇ
ꢋꢑ ꢉꢀ ꢁ ꢗ ꢁ
www.ti.com
SBAS274E − MARCH 2003 − REVISED JUNE 2004
associated ground, as shown in Figure 27. Each main
supply bus should also be bypassed with a bank of
capacitors from 47µF to 0.1µF, as shown.
The IO and digital supplies (IOVDD and DVDD) can be
connected together when using the same voltage. In this
case, only one bank of 47µF to 0.1µF capacitors is needed
on the main supply bus, though each supply pin must still
be bypassed with a 1µF and 0.1µF ceramic capacitor.
POWER SUPPLIES
Three supplies are used on the ADS1605/6: analog
(AVDD), digital (DVDD) and digital I/O (IOVDD). Each
supply must be suitably bypassed to achieve the best
performance. It is recommended that a 1µF and 0.1µF
ceramic capacitor be placed as close to each supply pin as
possible. Connect each supply-pin bypass capacitor to the
DVDD
µ
µ
µ
1 F
µ
0.1 F
47 F
4.7 F
IOVDD
AVDD
µ
µ
1 F
47 F
µ
µ
0.1 F
4.7 F
CP
CP
CP
µ
µ
0.1 F
4.7 F
µ
47 F
µ
1 F
58
57
55
54
53
52
51
1
AGND
AVDD
CP
2
3
If using separate analog and
digital ground planes, connect
together on the ADS1605/6 PCB.
6
AGND
CP
ADS1605
ADS1606
AVDD
AGND
7
9
DGND
AGND
µ
µ
NOTE: CP = 1 F 0.1 F
CP
AVDD
AGND
10
11
CP
12
AVDD
18
19
25
CP
26
CP
Figure 27. Recommended Power-Supply Bypassing
26
BB [ BURR-BROWN CORPORATION ]
