ES51967
6,600 Counts Auto DMM
1.1.3 The true RMS-to-DC conversion with ES636
If ES636 is used for true RMS-to-DC measurement, the test circuit is shown in Figure 1.
Make ADO and ADI pin short, and keep TEST5 pin float. Connect OVSG pin to
AGND through a switch in ACV measurement mode.
OVSG
99.5
ACV
OR1
1K
10K
101K
1.111M
VR5
VR4
VR3
VR2
-Vs +Vs
5K
TEST5
ACVL
4
4.7u
+
7
2
3
10K
+Vs
6
TL061
ACVH
5
4.7u
-Vs
N2
14
13
12
11
10
9
1
2
3
4
5
6
7
1
N1
100K
1.5K
-Vs
100
+Vs
8
1K
1M
+Vs
500K
-Vs
ADOHZ
10K
10K
100K
-Vs
3.3u
0.47u
ADI
ADO
AGND
Figure 1. The true RMS-to-DC conversion with ES636
V2.6
8
08/10/06
CYRUSTEK [ Cyrustek corporation ]
