ES51925
3000 Counts Smart DMM
Application Circuit
a.) AC average rectified circuit
1
2
3
4
5
6
V-
BT1
ZR3
3V
5.6V
uA
SW2
SW1
D
C
B
A
D
C
B
A
LCD Panel
C3
C4
10uF
ZR1
R1
ZR2
SW SPDT
0.1uF
450
J1
uA
SW3
ZR4
SEG01
SEG02
SEG03
SEG04
SEG05
SEG06
SEG07
SEG08
SEG09
SEG10
SEG11
SEG12
SEG13
SEG14
SEG15
BP1
C1
10uF
1
2
3
4
5
6
7
8
7.5V
C2
0.1uF
R2
45
mA
mA
60A
SW4
9
U1
10
11
12
13
14
15
16
17
18
19
R3
ZR5
ZR6
4.5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
SEG12
SEG13
SEG14
SEG15
CLAMP
VON
AON
FA
FUA
FC3
FC2
FC1
HOLD
SEL
VAHZ
RANGE
AGND
SEG12
SEG13
SEG14
SEG15
CLAMP
VON
AON
FA
FUA
FC3
FC2
FC1
HOLD
SEL
VAHz
RANGE
NC
BKLIT
EFEN
BP1
BP2
BP3
SW5
C9
LBAT
220nF
220nF
LBAT
CREF+
CREF-
CINT
CAZ
BUFF
RAZ
IVSH
IVSL
OVX
OVH
OVSG
OR1
VR5
VR4
VR3
VR2
TEST5
ACVL
ACVH
ADI
ADO
OHMC4
OHMC3
C7
C8
0.1uF
BP2
BP3
BP4
R4
0.495
R7
R8
R9
220K
75K
100K
100K
60A
CON19
SW6
1
1
IVSH
IVSL
100K
R10
J2
J4
R6
R5
R11
100
C6
ES51925
VR1
20K
R12
R13
R14
R15
R18
100
1K
10K
101K
1.11M
TEST5
ACVL
ACVH
ADI
Function Switch
0.005
Gnd
220pF
V -
V -
SW7
1.5K PTC
ZR8
R17
BKLIT
EFEN
BP1
BP2
BP3
SW SPST
VR1_10M
SW13
BKLIT
RANGE
VAHZ
SEL
SW8
CLAMP
VON
AON
FA
ZR7
R / C / D / Cont.
SW_non lock
SW_non lock
SW_non lock
SW_non lock
SW_non lock
SW_lock
SW14
1
ADO
BP4
ANNUNC
SW9
BP4
ANNUNC
BKOUT
J3
SW_lock
SW15
SW10
SW11
SW12
C11
22nF
C13
SW_lock
SW16
220nF
SW_lock
SW17
Average Circuit
C14
C15
470nF
47nF
HOLD
FUA
FC3
SW_lock
SW18
VR2
10K
R16
10K
TEST5
ADI
SW_lock
SW19
C10
4.7uF
APOSEL
BUZIN
SLEEP
FC2
C12
1uF
SW_lock
SW20
FC1
R21
15K
R22
15K
R23
27K VR3
10K
SW_lock
SW21
VR
R26
9K
EFEN
C17
1uF
D2
SW_lock
V -
D1
ACVH
ADO
C18
ZR9
5.6V
ADP
1N4148
IN4148
220nF
R25
1K
1
J5
BZ1
Buzzer
ACVL
Title
ES51925 3000 Counts Smart DMM
Size
B
Number
Revision
Application Circuit ( Average )
Date:
File:
30-Aug-2007
D:\Protel file\ES51928 Serial.ddb
Sheet of
Drawn By:
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Notes:
1. The ESD protection circuits protect most of pins. However pins, V+, V-, AGND, DGND and VR1
are not protected enough because the parasitic effect must be decrease. Therefore enough external
protection is needed for assembling, carrying and keeping. In addition, components connecting to
these unprotected pins have to be soldered on board before the IC is soldered.
2. All the zener diodes above are used for IC protection. These protections are needed and these zener
diodes must be soldered on PCB first before soldering ES51925 on.
3. The OVX pin resistance have to be kept below 120kΩ for the capacitance mode accuracy (3/30nF
range). For higher voltage protection, additional configuration of PTC protection is necessary.
Ver 2.9
20
10/06/25
CYRUSTEK [ Cyrustek corporation ]
