CYRUSTEK ES51970

ES51970(6000counts)
DMM Analog front end with Inrush
Features
• 6000 counts dual-slope SADC (2-5 cnvs/s.)
• Input signal full scale: 630mV (Max. 6300 count)
• Built-in 600 counts fast speed (x10) FADC
• Fast ADC conversion rate: 20-50 times/s
• 100L LQFP package
• 3V DC regulated power supply
• Support digital multi-meter function
*Voltage measurement (AC/DC)
*Current measurement (AC/DC)
*Dual mode for frequency with voltage or current
*Resistance measurement (600.0Ω – 60.00MΩ)
*Capacitance measurement (6.000nF – 60.00mF)
(Taiwan patent no.: 323347, 453443)
*Diode or continuity mode measurement
*Frequency counter with duty cycle display:
60.00Hz – 60.00MHz
5% – 95%
• ADP mode (AC or DC mode is available)
• 3dB BW selectable for low pass filter at AC mode
(Taiwan patent no.: 362409)
(China patent no.: 1363073)
Description
ES51970 is an analog frond end chip of
DMM built-in 6000(SADC)/600(FADC)
counts dual ADCs. The SADC is operated at
slower speed for higher resolution. The
FADC is operated at higher speed for lower
resolution. ES51970 provides voltage &
current (AC/DC) measurement, resistance
measurement, capacitance measurement,
diode/continuity measurement, frequency
measurement, duty cycle measurement and
inrush current measurement mode. The
ES51970 also supports multi-level battery
detection, low-pass-filter feature for AC mode
and dual mode measurement for V+F & A+F.
A 3-wire serial bus for MPU I/O port will be
used easily for firmware design. Flexible
function design is supported for different
kinds of DMM or Clamp-on meter
application.
.
• Band-gap reference voltage output
• 3-wire serial bus for MPU I/O port
• MPU I/O power level selectable by external pins
• On-chip buzzer driver and frequency selectable by
MPU command
• High-crest-factor signal detection
(Taiwan patent no.: 234661)
• Multi-level battery voltage detection
• Support sleep mode by external chip select pin
• Support Inrush current measurement mode
Application
Clamp-on meter
ver 2.8
1
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
Pin Assignment
2
3
4
6
5
D
C
BUFH
CAZH
NC
CL+
CLCIL
CAZL
BUFL
RAZ
OHMC3
OHMC2
OHMC1
VRH
VA+
VAEXTSRC
NC
NC
OR1
VR5
VR4
VR3
VR2
OVSG
VR1
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
FREQ
STBEEP
NC
NC
NC
LPFOUT
LPC3
LPC2
LPC1
R1K
R9K
NC
NC
CSHCSH+
ES51970
D
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
C
B
OVX
OVH
OVH1
NC
NC
NC
NC
NC
NC
NC
SGND
IVSH
IVSL
ADP
OPINOPIN+
OPOUT
ACVL
ACVH
ADI
ADO
TEST5
CACA+
OHMC4
B
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
CIH
CHCH+
AGND
AGND
DGND
V+
V+
uPVCC
VVLBAT
CC+
SDATA
SCLK
DATA_new
NC
BZOUT
IO_CTRL
CS
OSC1
OSC2
NC
NC
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
1
A
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
A
1
ver. 2.8
2
3
4
2
5
6
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
Pin Description
Pin No
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Symbol
BUFH
CAZH
NC
CL+
CLCIL
CAZL
BUFL
RAZ
OHMC3
OHMC2
OHMC1
VRH
VA+
Type
O
O
IO
IO
O
O
O
O
O
O
O
O
I
15
VA-
I
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
EXTSRC
NC
NC
OR1
VR5
VR4
VR3
VR2
OVSG
VR1
OVX
OVH
OVH1
NC
NC
NC
NC
NC
NC
NC
SGND
IVSH
IVSL
ADP
OPINOPIN+
OPOUT
ACVL
I
O
O
O
O
O
O
I
I
O
O
G
I
I
I
I
I
O
O
44
ACVH
O
45
46
47
48
49
ADI
ADO
TEST5
CACA+
I
O
O
IO
IO
ver. 2.8
Description
High-speed buffer output pin. Connect to integral resistor.
High-speed auto-zero capacitor connection.
Not connected
Positive connection for reference capacitor of high-resolution A/D.
Negative connection for reference capacitor of high- resolution A/D.
High-resolution integrator output. Connect to integral capacitor.
High-resolution auto-zero capacitor connection.
High-resolution Buffer output pin. Connect to integral resistor
Buffer output pin in AZ and ZI phase.
Filter capacitor connection for resistance mode.
Filter capacitor connection for resistance mode.
Filter capacitor connection for resistance mode.
Output of band-gap voltage reference. Typically –1.23V
De-integrating voltage positive input. The input should be higher than
VA-.
De-integrating voltage negative input. The input should be lower than
VA+.
External source input available for Res/Diode/ADP mode
Not connected
Not connected
Reference resistor connection for 600.0Ω range
Voltage measurement ÷10000 attenuator(1000V)
Voltage measurement ÷1000 attenuator(600.0V)
Voltage measurement ÷100 attenuator(60.00V)
Voltage measurement ÷10 attenuator(6.000V)
Sense low voltage for resistance/voltage measurement
Measurement Input. Connect to a precise 10MΩ resistor.
Sense input for resistance/capacitance measurement
Output connection for resistance measurement
Output connection1 for resistance measurement (optional)
Not connected
Not connected
Not connected
Not connected
Not connected
Not connected
Not connected
Signal Ground.
Current measurement input for 6000μA, 600mA and 60A modes.
Current measurement input for 600μA, 60mA.
Measurement input in ADP mode.
Independent operational amplifier negative input
Independent operational amplifier positive input
Independent operational amplifier output
DC signal low input in ACV/ACA mode. Connect to negative output
of external AC to DC converter.
DC signal high input in ACV/ACA mode. Connect to positive output
of external AC to DC converter.
Negative input of internal AC-to-DC OPAMP.
Output of internal AC-to-DC OPAMP.
Buffer output of OVSG
Negative auto-zero capacitor connection for capacitor measurement
Positive auto-zero capacitor connection for capacitor measurement
3
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
OHMC4
CSH+
CSHNC
NC
R9K
R1K
LPC1
LPC2
LPC3
LPFOUT
NC
NC
NC
STBEEP
O
I/O
I/O
O
O
O
O
O
O
O
65
66-77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
FREQ
NC
OSC2
OSC1
CS
IO_CTRL
BZOUT
TEST
DATA_NEW
SCLK
SDATA
C+
CLBAT
VVuPVCC
V+
V+
DGND
AGND
AGND
CH+
CHCIH
I
O
I
I
I
I
O
I
IO
O
O
I
P
P
P
O
O
G
G
G
IO
IO
O
ver. 2.8
Filter capacitor connection for resistance mode.
Capacitor connection for inrush mode
Capacitor connection for inrush mode
Not connected
Not connected
Connect to a precise 9KΩ resister for capacitor measurement.
Connect to a precise 1KΩ resister for capacitor measurement.
Capacitor C1 connection for internal low-pass filter
Capacitor C2 connection for internal low-pass filter
Capacitor C3 connection for internal low-pass filter
Capacitor C1 connection for internal low-pass filter
Not connected
Not connected
Not connected
Fast low-impedance sensed output for CONT./Diode mode Build-in a
internal comparator for OVX pin.
Frequency counter input, offset V-/2 internally by the chip.
Not connected
Crystal oscillator output connection
Crystal oscillator input connection
Set to high to enable ES51970. Set to low to enter sleep mode
MPU I/O level LOW setting. Connect to DGND or V-.
Buzzer frequency output. Normal low state.
Test mode used. Not connected
New ADC data ready
Serial clock input
Serial data input/output
Positive capacitor connection for on-chip DC-DC converter.
Negative capacitor connection for on-chip DC-DC converter.
Low battery configuration input.
Negative supply voltage.
Negative supply voltage.
Switch 5 for function selection.
Output of on-chip DC-DC converter.
Output of on-chip DC-DC converter.
Digital ground.
Analog ground.
Analog ground.
Positive connection for reference capacitor of high-speed A/D.
Negative connection for reference capacitor of high-speed A/D.
High-speed integrator output. Connect to integral capacitor.
4
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
Absolute Maximum Ratings
Characteristic
Supply Voltage (V- to AGND)
Analog Input Voltage & EXTSRC pin
V+
AGND/DGND
Digital Input (IO_CTRL=V-)
Power Dissipation. Flat Package
Operating Temperature
Storage Temperature
Rating
-4V
V- -0.6 to V+ +0.6
V+ ≥ (AGND/DGND+0.5V)
AGND/DGND ≥ (V- -0.5V)
V- -0.6 to uPVCC+0.6
500mW
0℃ to 70℃
-55℃ to 125℃
Electrical Characteristics
TA=25℃, V- = -3.0V
Parameter
Power supply
Operating supply current
In DCV mode
Symbol
Test Condition
VIDD Normal operation
ISS In sleep mode
SADC2 Voltage roll-over error
10MΩ input resistor
FADC3 Voltage roll-over error
10MΩ input resistor
Best case straight
NLV1
line
Best case straight
NLV2
line
VA+-VA- = 200mV
VA+-VA- = 200mV
SADC2 voltage nonlinearity
FADC3 voltage nonlinearity
Voltage full scale range of SADC2
Voltage full scale range of FADC3
Input Leakage for VR1 input
Zero input reading
Band-gap reference voltage
VRH
Open circuit voltage for 600Ω range
measurement
Open circuit voltage for other Ω
measurement
Between V- pin and
CS
Internal pull-high to 0V
current
AC frequency response at 6.000V
range
OP unity gain bandwidth
OP slew rate at unity gain
OP input offset voltage
OP input bias current
OP input common mode
voltage range
3dB frequency for LPF4 active
ver. 2.8
10MΩ input resistor
100KΩ resistor
between VRH and
AGND
GB
SR
VIO
IB
±1%
±5%
CL=10pF
RL=10MΩ
VICR
f3dB
3dB=Full (ADP)
3dB=10k (ADP)
3dB=1k (ADP)
5
Min.
-2.8
—
—
—
Typ.
-3.0
2.8
1
—
Max
-3.2
3.2
3
Units
V
mA
µA
±0.1
%F.S1
—
—
±0.5
%F.S1
—
—
±0.1
%F.S1
—
—
±1.0
%F.S1
—
—
-10
-000
600
600
1
000
630
—
10
+000
mV
mV
pA
Count
-1.30
-1.22
-1.14
V
—
V-
—
V
—
VRH
—
V
—
1.2
—
µA
—
—
—
—
—
—
40-400
400-2000
200
3.5
0.1
10
—
—
—
—
—
—
kHz
V/us
mV
pA
—
+2
—
V
100
—
—
—
10
1
—
—
—
kHz
kHz
kHz
HZ
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
LBAT vs. V-
—
—
—
2.15
2.03
1.83
—
—
—
V
V
V
STBEEP comparator in Diode mode
OVX to SGND
—
+9
—
mV
STBEEP comparator in Cont. mode
OVX to SGND
—
-7
—
mV
HCF detection voltage
VR2-VR5
—
1100
—
mV
—
100
—
ms
Multi-level low battery detector
Vt1
Vt2
Vt3
Inrush measurement integration time
Frequency input sensitivity (FREQ)
Fin
Square wave with
Duty cycle 40-60%
500
—
—
mVp
Frequency input sensitivity (FREQ)
Fin
Sine wave
400
—
—
mVrms
100KΩ
resister
VRH
TCRF Between
0℃<TA<70℃
—
50
—
ppm/℃
-2.5
—
2.5
%F.S
-3
—
3
counts
Reference voltage temperature
coefficient
Capacitance measurement
Accuracy5
6.0nF – 60mF
Note:
1. Full Scale (6000 counts for SADC and 600 counts for FADC)
2. SADC = High resolution ADC (slow speed)
3. FADC = High speed ADC (lower resolution)
4. ES51970 built-in 3rd order low pass filter available for AC mode
5. Gain calibration is necessary for higher accuracy
ver. 2.8
6
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
AC electrical characteristics
Parameter
Symbol
Min.
Typ.
Max.
Unit
SCLK clock frequency
SCLK clock time “L”
SLCK clock time “H”
SDATA output delay time
SDATA output hold time
Start condition setup time
Start condition hold time
Data input setup time
Data input hold time
Stop condition setup time
SCLK/SDATA rising time
SCLK/SDATA falling time
Bus release time
EOC setup time in read mode
EOC hold time in read mode
fSCLK
tLOW
tHIGH
tAA
tDH
tSU.STA
tHD.STA
tSU.DAT
tHD.DAT
tSU.STO
tR
tF
tBUF
tSU.EOC
tHD.EOC
4.7
4.0
0.1
100
4.7
4.0
200
0
4.7
4.7
0
0
-
100
3.5
1.0
0.3
-
kHz
-
-
us
ns
us
ns
us
ns
ns
MPU I/O timing diagram
SCLK
SDATA IN
SDATA OUT
ver. 2.8
7
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
Function Description
1. MPU serial I/O function overview
1.1 Introduction
ES51970 configures a 3-wire serial I/O interface to external microprocessor unit (MPU).
The SDATA pin is bi-directional and SCLK & DATA_NEW are unilateral. The SDATA pin
is configured by open-drain circuit design. The DATA_NEW is used to check the data
buffer of ADC ready or not. When the ADC conversion cycle is finished, the DATA_NEW
pin will be pulled high until MPU send a valid read command to ES51970. After the first ID
byte is confirmed, the DATA_NEW will be driven to low until the next ADC conversion
finished again.
The data communication protocol is shown below. The write protocol is configured by an
ID byte with four command bytes. The read protocol is configured by an ID byte with ten
data bytes.
Write command:
ID byte, Write control byte1, Write control byte2, Write control byte3, Write control byte4
START BIT
1
1
0
0 1
0
B
U
Z 0
A
C
K
A
C
K
A
C
K
A
C
K
A
C
K
STOP BIT
WRITE
Read command:
ID byte, Read data byte1, Read data byte2 ~ Read data byte9, Read data byte10
START BIT
1
1
0
0 1
A
C
K
B
U
0 Z 1
A
C
K
A
C
K
A
C
K
READ
A
C
K
N
A
K
STOP BIT
DATA_NEW
ADC data ready
ID code confirmed
Next ADC data ready
ID code
SDATA
1
1
0
0
1
0
1
Read command
SCLK
Start bit
ver. 2.8
Stop bit
8
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
The ID byte of ES51970 is header of “110010” followed by a buzzer on/off control bit and
R/W bit. The start/stop bit definition is shown on the diagram below.
1.2 Read/Write command description
The write command includes one ID byte with four command bytes. If the valid write ID
code is received by ES51970 at any time, the write command operation will be enabled.
The next table shows the content of write command.
Byte
Bit7
Bit6
Bit5
Bit4
Bit3
ID
W1
W2
W3
W4
1
SHBP
B0
AC
0
1
F3
B1
0
0
0
F2
B2
0
0
0
F1
C0
EXT
INA
1
F0
C1
FS60
0
Bit2
0
Q2
FQ2
LPF1
OP0
Bit1
BUZ
Q1
FQ1
LPF0
OP1
Bit0
R/W=0
Q0
FQ0
FRES
EXT_ADP
Auxiliary low-resistance detection control bit for Continuity and Diode modes: SHBP
Measurement function control bit: F3/F2/F1/F0
Range control bit for V/A/R/C modes: Q2/Q1/Q0
Range control bit for Freq mode: FQ2/FQ1/FQ0
Buzzer frequency selection: B2/B1/B0
Buzzer driver ON/OFF control bit: BUZ
ADC conversion rate control bit: C1/C0
AC mode control enable bit: AC
3dB BW for low-pass-filter selection: LPF1/LPF0
External source for Diode mode control bit: EXT
Inrush mode control bit: INA
OP configuration control bit: OP1/OP0
Frequency mode input resistance control bit: FRES
ADP mode control bit: EXT_ADP
ADP DC mode full scale control bit: FS60
ver. 2.8
9
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
The read command includes one ID byte with ten data bytes. When DATA_NEW is ready1,
MPU could send the read data command to get the result of ADC conversion
(D0/D1/D2/D3)2 or status flag from ES51970.
The next table shows the content of read command.
Byte
Bit7
Bit6
Bit5
Bit4
ID
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
1
ASIGN
HF
D0:3
D0:11
D1:0
D1:8
D2:6
D2:14
D3:3
D3:11
1
BSIGN
LF
D0:4
D0:12
D1:1
D1:9
D2:7
D2:15
D3:4
D3:12
0
X
LDUTY
D0:5
D0:13
D1:2
D2:0
D2:8
D2:16
D3:5
D3:13
0
X
STA1
D0:6
D0:14
D1:3
D2:1
D2:9
D2:17
D3:6
D3:14
Bit3
1
BTS0
F_FIN
D0:7
D0:15
D1:4
D2:2
D2:10
D2:18
D3:7
D3:15
Bit2
0
BTS1
D0:0
D0:8
D0:16
D1:5
D2:3
D2:11
D3:0
D3:8
D3:16
Bit1
BUZ
STA0
D0:1
D0:9
D0:17
D1:6
D2:4
D2:12
D3:1
D3:9
D3:17
Bit0
R/W=1
ALARM
D0:2
D0:10
D0:18
D1:7
D2:5
D2:13
D3:2
D3:10
D3:18
1
Note: DATA_NEW will be active with D1 data updated when one fast ADC (FADC) conversion finished. If
MCU access slow ADC output only, ten FADC conversion cycle delay is necessary. DATA_NEW for
frequency or capacitance mode will be active when D0 or D3 data ready.
2
Note: D0/D1/D2/D3 all are binary code format. D0 is SADC output and D1 is FADC output
The ADC data output for measurement mode: F3/F2/F1/F0
F3
F2
F1
F0
Measurement mode
0
0
0
0
V mode
0
0
0
1
ACV + Hz mode
0
0
1
0
A mode
0
0
1
1
ACA + Hz mode
D0(0:18), D1(0:9), D3(0:18)
0
1
0
0
Resistance mode
D0(0:18), D1(0:9)
0
1
0
1
Continuity mode
D0(0:18), D1(0:9)
0
1
1
0
Diode mode
D0(0:18), D1(0:9)
0
1
1
1
F + duty mode
1
0
0
0
Capacitance Mode
1
0
0
1
ADP mode
1
0
1
0
ADP + Hz mode
ver. 2.8
10
Read data bytes
D0(0:18), D1(0:9)
D0(0:18), D1(0:9), D3(0:18)
D0(0:18), D1(0:9)
D0(0:18), D2(0:18), D3(0:18)
D0(0:18)
D0(0:18), D1(0:9)
D0(0:18), D1(0:9), D3(0:18)
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
Buzzer frequency selection: B2/B1/B0
B2
B1
B0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
Buzzer frequency
1.00kHz
1.33kHz
2.00kHz
2.22kHz
2.67kHz
3.08kHz
3.33kHz
4.00kHz
Set B2-B0 properly to get the target frequency. Use BUZ control bit to enable/disable the
BUZOUT (pin82) driver output. If MPU control BUZ only, it is available to set ID byte with
ending of stop bit.
START BIT
A
R C
1 1 0 0 1 0 0 /W K
STOP BIT
Buzzer OFF
START BIT
R
1 1 0 0 1 0 1 /W
STOP BIT
Buzzer ON
ADC conversion rate selection: C1/C0
C1
C0
SADC Conversion Time
(High resolution ADC)
0
0
500ms
0
1
300ms
1
0
250ms
1
1
200ms
FADC Conversion Time
(High speed ADC)
50ms
30ms
25ms
20ms
SADC Line
noise rejection
50/60Hz
50Hz
60Hz
50Hz
Set C1-C0 to change the target conversion rate for SADC & FADC simultaneously.
ver. 2.8
11
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
Status flags for measurement mode: ● = function available
Measurement mode
V mode
ACV + Hz mode
A mode
ACA + Hz mode
Res. mode
Cont. mode
Diode mode
F + duty mode
Cap. Mode
ADP mode
ADP + Hz mode
Measurement mode
V mode
V + Hz mode
A mode
A + Hz mode
Res. mode
Cont. mode
Diode mode
F + duty mode
Cap. Mode
ADP mode
ADP + Hz mode
ASIGN
●
BSIGN
●
●
●
●
●
●
●
HF
LF
●
BTS0
●
●
●
●
●
●
●
●
●
●
●
LDUTY
BTS1
●
●
●
●
●
●
●
●
●
●
●
STA0
ALARM
●
●
●
●
STA1
F_FIN
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
Description of status flags:
ASIGN: Sign bit of SADC output (-1 * D0 if ASIGN=1)
BSIGN: Sign bit of FADC output (-1 * D1 if BSIGN=1)
BTS0/BTS1: Multi-level battery voltage indication
ALARM: Large capacitor indication/High crest factor signal detection in ACV mode/Inrush
mode waiting triggered
HF: Higher frequency indication for Hz mode
LF: Lower frequency indication for Hz mode
LDUTY: Low duty indication for Hz + duty mode
STA0/STA1: divider indication for Hz mode
STA0: Status flag for capacitor discharging mode
F_FIN: Measurement cycle finished for Hz mode / Inrush integration cycle finished
ver. 2.8
12
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
1.3 Power & I/O level selection
The ES51970 provide a flexible I/O level setting for different MPU system configuration.
The uP_VCC should be connected to the same potential of external Vcc of MCU. The
uP_VCC is allowed to be set between DGND ~ V+. The IO_CTRL pin selects the Vss level
of MCU. If IO_CTRL is set to DGND, the Vss level of MCU is the same as DGND. If
IO_CTRL is set to V-, the Vss level of MCU is the same as V-.
ver. 2.8
13
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.
Operating Modes
2.1. Voltage Measurement
MPU send write command to select the voltage measurement function. The Hz mode
measurement is available to be enabled with the ACV function (set AC bit to 1)
simultaneously. The measured signal is applied to VR1 terminal (pin25) through 10MΩ.
See the next table of function command:
F3
F2
F1
F0
AC
Measurement mode
Read data bytes
0
0
0
0
0
DCV mode
D0(0:18), D1(0:9)
0
0
0
0
1
ACV mode
D0(0:18), D1(0:9)
0
0
0
1
1
ACV + Hz mode
D0(0:18), D1(0:9), D3(0:18)
Note1: D0/D1/D2/D3 all are binary format. ASIGN/BSIGN are the sign bit of D0/D1, respectively.
Range control for voltage mode (ACV/DCV)
Q2
0
0
0
0
1
Q1
0
0
1
1
0
Q0
0
1
0
1
0
Full Scale Range
600.0mV
6.000V
60.00V
600.0V
1000V
Divider Ratio
1
1/10
1/100
1/1000
1/10000
Resister Connection
VR1 (10MΩ)
VR2 (1.111MΩ)
VR3 (101kΩ)
VR4 (10.01kΩ)
VR5 (1kΩ)
Frequency range control for ACV+Hz mode
FQ2 FQ1 FQ0
0
0
0
0
0
1
0
1
0
0
1
1
Full Scale Range
60.00Hz
600.0Hz
6.000kHz
60.00kHz
Note: See frequency mode (section 2.8) also
ALARM bit at voltage mode is used for high crest factor (HCF) signal detection. If MPU
check the ALARM status flag active when data and range are stable, it should consider the
making the existing range up to avoid the signal clamping saturation caused by HCF signal.
There is higher peak voltage with lower RMS value for HCF signal. So if the range is up
according to the ALARM bit, MCU should set the lower under-limit counts temporarily to
avoid the ranging unstable for this case.
ver. 2.8
14
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.2 Current measurement
MPU send write command to select the current measurement function. The Hz mode
measurement is available to be enabled with the ACA function (set AC bit to 1)
simultaneously. The measured signal is applied to IVSL/IVSH terminals (pin37-38).
See the next table of function command:
F3
F2
F1
F0
AC
Measurement mode
Read data bytes
0
0
1
0
0
DCA mode
D0(0:18), D1(0:9)
0
0
1
0
1
ACA mode
D0(0:18), D1(0:9)
0
0
1
1
1
ACA + Hz mode
D0(0:18), D1(0:9), D3(0:18)
Note1: D0/D1/D3 all are binary format. ASIGN/BSIGN are the sign bit of D0/D1, respectively.
Range control for current mode (ACA/DCA)
Q2
0
0
Q1
0
0
Q0
0
1
Full Scale Range
300mV 6000counts
300mV 6000counts
Input terminal
IVSL
IVSH
Current measurement mode configuration example: (max. voltage drop 300mV)
90K
600.0 / 6000uA
60.00 / 600.0mA
49.5
4
uA / mA
V- V+
10K
2
TL061
+
100K
6
IVSL
5
3
7
FUSE
1
FUSE
1
V+
100K
6A/ 20A
0.1uF
A
V-
1
V-
0.495
0.1uF
1.5K
Zero Offset
0.005
100K
1
COM
0.005
0.045
0.45
4.5
A
mA
uA
ver. 2.8
45
450
(max voltage drop = ~ 1V)
AGND
SGND
20A
6A
IVSH
mA
mA
uA
uA
100K
100K
IVSH
IVSL
15
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
Frequency range control for ACA+Hz mode
FQ2 FQ1 FQ0
0
0
0
0
0
1
0
1
0
0
1
1
Full Scale Range
60.00Hz
600.0Hz
6.000kHz
60.00kHz
Note: See frequency mode (section 2.8) also.
2.3 Low pass filter (LPF) mode for ACA/ACV mode
A 3rd order low pass filter with is built in ES51970. The 3dB bandwidth of the low pass
filter could be selectable by MPU. The LPF mode is active when the LPF control bit is set
to be active.
The LPF mode is allowed to be enabled in F + duty mode to reject high-frequency noise
for sine wave input, but the 3dB will be fixed at 10kHz only.
LPF1
LPF0
Low pass filter effect
0
0
Disable
0
1
3dB = 1kHz
1
0
3dB = 10kHz
1
1
3dB > 100kHz
2.4 Resistance Measurement
MPU send write command to select the resistance measurement function.
F3
F2
F1
F0
Measurement mode
0
1
0
0
Resistance mode
Read data bytes
D0(0:18), D1(0:9)
Note1: D0/D1 both are binary format. ASIGN/BSIGN bits are ignored.
Range control for resistance mode
Q2
0
0
0
0
1
1
ver. 2.8
Q1
0
0
1
1
0
0
Q0
0
1
0
1
0
1
Full Scale Range
600.0Ω
6.000KΩ
60.00KΩ
600.0KΩ
6.000MΩ
60.00MΩ
Relative Resistor
OR1
VR5
VR4 || VR1
VR3 || VR1
VR2 || VR1
VR1
16
Equivalent value
100Ω
1KΩ
10KΩ
100KΩ
1MΩ
10MΩ
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.5 Capacitance Measurement
MPU send write command to select the capacitance measurement function.
F3
F2
F1
F0
Measurement mode
1
0
0
0
Capacitance mode
Read data bytes
D0(0:18)
Note1: D0 is binary format. ASIGN bit is ignored.
Range control for capacitance mode
Q2
0
0
0
0
1
1
1
1


Q1
0
0
1
1
0
0
1
1
Q0
0
1
0
1
0
1
0
1
Full Scale Range
6.000nF
60.00nF
600.0nF
6.000uF
60.00uF
600.0uF
6.000mF
60.00mF
Relative Resistor
OVX pin VR
R9K / R1K
R9K / R1K
R9K / R1K
R9K / R1K
R9K / R1K
Measurement Period
0.5 sec
0.5 sec
1.25 sec
0.4 sec max.
0.5 sec max.
1.0 sec max.
1.35 sec max.
6.75 sec max.
ALARM bit at capacitance mode is used for increasing the ranging speed. If MPU
check the ALARM=1 at lower range, it could set the next range to 6.000uF directly
and the ADC output should be ignored.
STA0 status bit is used for detection of DUT capacitor voltage. If STA0=1, the internal
capacitor discharging mode is active and the capacitance measurement is inhibited. It is
recommended to discharge the DUT capacitor externally.
2.6 Continuity Check measurement
MPU send write command to select the continuity measurement function.
F3
F2
F1
F0
Measurement mode
0
1
0
1
Continuity mode
Read data bytes
D0(0:18), D1(0:9)
Note1: D0/D1 both are binary format. ASIGN/BSIGN bits both are ignored.
Continuity mode shares the same configuration with 600.0Ω resistance measurement circuit
and support the low-resistance detection. If the STBEEP output (pin64) is low, it means the
low-resistance status is detected (It means the OVX terminal voltage less than -7mV). It
could be faster than the FADC result, so MPU could monitor the STBEEP output and FADC
(D1) data output make the high speed detection for short circuit detection. Set SHBP=1 to
enable the built-in buzzer driving automatically when STBEEP is active.
ver. 2.8
17
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.7 Diode Measurement
MPU send write command to select the diode measurement function.
F3
F2
F1
F0
Measurement mode
0
1
1
0
Diode mode
Read data bytes
D0(0:18), D1(0:9)
Note1: D0/D1 both are binary format. ASIGN/BSIGN are the sign bit of D0/D1, respectively.
Diode measurement mode shares the same configuration with 6.000V voltage measurement
circuit and support the low-resistance detection. If the STBEEP output (pin64) is low, it
means the low-resistance status is detected (It means the OVX terminal voltage less than
9mV). It could be faster than the FADC result, so MPU could monitor the STBEEP output
and FADC (D1) data output make the high speed detection for short circuit detection. Set
SHBP=1 to enable the built-in buzzer driving automatically when STBEEP is active.
The default source voltage at diode mode is the same as V+ potential. MPU could set the
control bit EXT=1 to change the source voltage to external source. The external voltage
source (positive or negative) input applied from EXTSRC (pin16). The available external
source range should be from V+ to V-.
ver. 2.8
18
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.8 Frequency/duty cycle mode measurement
The default typical input impedance of frequency with duty cycle mode is 1MΩ. The MPU
could set control bit FRES=1 to change the input impedance down to 100kΩ. The MPU
send write command to select the frequency/duty cycle measurement function.
F3
F2
F1
F0
Measurement mode
0
1
1
1
Hz + Duty mode
Read data bytes
D0(0:18), D2(0:18), D3(0:18)
Note1: D0/D2/D3 all are binary format. ASIGN bit is ignored.
Note2: Set LPF1 = 1 to enable the smooth function for sine wave input automatically
Range control for frequency mode
FQ2
0
0
0
0
1
1
1
FQ1
0
0
1
1
0
0
1
FQ0
0
1
0
1
0
1
0
Full Scale
60.00Hz
600.0Hz
6.000KHz
60.00KHz
600.0KHz
6.000MHz
60.00MHz
Available minimum frequency input (Depends on ADC conversion rate setting)
C1
0
0
1
1
C0
0
1
0
1
FMIN(AC+Hz mode) FMIN(Hz+Duty mode)
4.00Hz
6.00Hz
4.00Hz
8.00Hz
10.00Hz
Frequency & duty cycle mode computed by D0/D2/D3 (if F_FIN = 1)
Flag
STA0=0
STA0=1
Range
STA1=1
STA1=0
60.00Hz
FREQ=100000000/D3
FREQ=400000000/D3
FREQ=800000000/D3
600.0Hz
FREQ=10000000/D3
FREQ=40000000/D3
FREQ=160000000/D3
6.000KHz
FREQ=2000000/D3
FREQ=32000000/D3
FREQ=256000000/D3
60.00KHz
FREQ=200000/D3
FREQ=25600000/D3
FREQ=204800000/D3
600.0KHz
6.000MHz
FREQ = D0
60.00MHz
Status Flag
Duty cycle (<60kHz)
ver. 2.8
LDUTY=1
10000-D2*10000/D3
19
LDUTY=0
D2*10000/D3
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
The status flag F_FIN indicate the frequency input signal available (> FMIN) or not. If the
computed result less than FMIN, the frequency/duty cycle readings should be set to zero.
The status flags HF & LF are used for fast judgment of proper range. If frequency input is
larger than 7 kHz, HF will be active. If frequency input is floating or frequency detected too
low, LF will be active automatically.
Auto range consideration for MPU by using Status Flags of frequency mode
Flag
F_FIN=0
F_FIN=1
F_FIN=1
Range
LF=0
LF=1*
HF=LF=0
HF=1**
60.00Hz
Set Hz/Duty=0
Set range to
600.0Hz
60.00kHz range
6.000KHz
Change range
Data and Range
depends on data
60.00KHz
Set range to
is not necessary
Change range
computed
600.0KHz
60.00Hz range
to be updated
depends on data
6.000MHz
computed
60.00MHz
*Note: LF=1 @ 60Hz range implies the frequency is not available to be measured. The Hz/Duty readings
should be set to zero.
**Note: When ACV+Hz/ACA+Hz/ADP+Hz mode is selected, the HF status should be ignored. Change range
depends on data calculation result.
Duty cycle mode range (Input sensitivity > 2Vpp @ duty cycle= 5% or 95%)
Freq. range
Duty range
60.00Hz
600.0Hz
6.000KHz
10 % - 90%
60.00KHz
20% – 80%
ver. 2.8
5% - 95%
20
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.9 ADP mode
MPU send write command to select the ADP mode measurement function. The Hz mode
measurement is available to be enabled with the ADP AC function (set AC bit to 1)
simultaneously. The measured signal is applied to ADP terminal (pin39). The signal full
scale is 600mV for DC mode and 600mVrms for AC mode. The FS60 control bit is used for
ADP DC mode. When FS60=1, the full scale will be change from 600mV to 60mV. It
means the resolution will be improved to 0.01mV, but the ADC conversion rate will be
reduced to 0.9 /sec.
See the next table of function command:
F3
F2
F1
F0
AC
Measurement mode
Read data bytes
1
0
0
1
0
ADP DC mode
D0(0:18), D1(0:9)
1
0
0
1
1
ADP AC mode
D0(0:18), D1(0:9)
1
0
1
0
1
ADP + Hz mode
D0(0:18), D1(0:9), D3(0:18)
Note1: D0/D1/D3 all are binary format. ASIGN/BSIGN are the sign bit of D0/D1, respectively.
Frequency range control for ADP+Hz mode
FQ2 FQ1 FQ0
0
0
0
0
0
1
0
1
0
0
1
1
Full Scale Range
60.00Hz
600.0Hz
6.000kHz
60.00kHz
Note: See frequency mode (section 2.8) also
If MPU set the control bit EXT_ADP=1, the voltage on EXTSRC pin could be switched to
ADP terminal internally. It is helpful for a voltage pulled application of ADP mode.
External source
pull high or low
EXT_ADP
ADC IN+
ADP_IN
ADC IN-
SGND
ver. 2.8
21
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.10 Inrush measurement
F3
F2
F1
F0
AC
Measurement mode
Input terminals
Read data bytes
1
0
0
1
1
ADP AC mode
ADP
D0(0:18)
0
0
1
0
1
ACA mode
IVSH/IVSL
D0(0:18)
ES51970 provides an inrush function for AC current measurement of clamp-on meter to
dectect the starting-up current of a motor. Only ACA/ADP(AC) modes support inrush
measurement mode. SET control bit INA=1 of write command to enter the inrush function.
Initially, the status bit ALARM=1 means to wait for signal triggered (> 20mVp typ.). If the
external starting-up signal is applied and detected, ES51970 will execute the inrush
measurement. When the inrush measurement is finished, the status bit F_FIN=1 to indicate
the inrush integration cycle is finished. It means the ADC data is ready for access by MCU.
To enter inrush mode cycle again, set control bit INA=1 of write command and repeat the
procedures mentioned above. To exist inrush mode, set INA=0 of write command. For
INRUSH function, an external true RMS-to-DC ES636 IC is required. The flow chart of
inrush function is shown below.
ver. 2.8
22
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.11 Sleep
Set CS pin (pin 80) to logic low to make the ES51970 entering the sleep mode. The current
consumption will be less than 3uA typically. Set CS pin to logic high or kept floating, the
ES51970 will return to normal operation.
2.12 Multi-level battery voltage indication
The ES51970 is built-in a comparator for batter voltage indication. The voltage is applied to
LBAT pin (pin 89) vs. V- terminal. MPU could check the status bit BTS1/BTS0 and monitor
the LBAT voltage status.
Battery voltage
VLBT > Vt1
Vt2 < VLBT < Vt1
Vt3 < VLBT < Vt2
VLBT < Vt3
BTS1
1
1
0
0
BST0
1
0
1
0
Low battery configuration for 9V/1.5V*4/1.5V*3 battery
Low battery test circuit (a)
Low battery test circuit (b)
6V
9V
BA
360K
TT
BA
LBAT
0.1u
270K
470K
TT
AGND
V-
0.1u
180K
0V
LBAT
AGND
V-
0V
Low battery test circuit (c)
4.5V
BA
360K
TT
LBAT
0.1u
470K
AGND
V-
0V
ver. 2.8
23
12/01/12
ES51970(6000counts)
DMM Analog front end with Inrush
2.13 Independent OPAMP
ES51970 is built-in an independent OPAMP with low-drift offset using for general purpose.
MPU could control the OP1/OP0 to change the OPAMP configuration:
OP1
OP0
OPAMP configuration
0
0
Normal
0
1
OP disable
1
0
Unity gain buffer
1
1
Zero calibration
Independent OPAMP configuration
Normal operation
OPIN-
-
OPIN+
+
OPOUT
Zero offset calibration
OPIN-
-
OPIN+
+
OPOUT
Unity gain operation
ver. 2.8
OPIN-
-
OPIN+
+
OPOUT
24
12/01/12
1
220nF
+
C7
100nF
R5
R9
V-
47nF
C13
R1
22nF
470K
100
1K
10.01K
101K
1.111M
OVSG
10M
U1
BUFH
CAZH
NC
CL+
CLCIL
CAZL
BUFL
RAZ
OHMC3
OHMC2
OHMC1
VRH
VA+
VAEXTSRC
NC
NC
OR1
VR5
VR4
VR3
VR2
OVSG
VR1
SW2
ACV RMS
V+
2
V1-
ES51970
Y1
4MHz
Option
C31
5pF
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
FREQ
STBEEP
NC
NC
NC
LPFOUT
LPC3
LPC2
LPC1
R1K
R9K
NC
NC
CSHCSH+
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
C29
47nF
3
R12
VDD
47K
SDATA
SCLK
DATA_new
STBEEP
C20
Q2
VR3
500
R13
Q3
MPU
2.2uF
- VS
1
2
3
4
5
6
7
uPVCC (DGND or +3V)
4
VDD
4
+ VS
C26
10uF
C27
+
Revision
Ver : 9
10uF
- VS
Close toIC
ACVH
V- or DGND
+ VS
JP1
1
2
FIN
14
13
12
11
10
9
8
10K
R33
200
+
VSS
Q4
2.2K PTC
R34
500K
- VS
C23
4.7uF
U2
Vin
+ VS
En
NC
- VS
NC
CAV
NC
dB COMMON
BUF out
RL
BUF in
Iout
ES636
+ VS
VR4
Demo Board schematic
Number
2-Dec-2011
F:\Protelfile\KA029\KA029.ddb
Sheet of
Drawn By:
ES51970 Schematic Circuit (TRMS)
200K
3.3nF +/- 10%
ADI
+
+ VS
C25
22uF
R3
CS
Q1
200
470pF +/- 10%
C19
100pF +/- 10%
R32
9K
+
STBEEP
C14
C15
R1K
R9K
C22
1uF
R26
1K
Title
Size
A4
Date:
File:
+
OVH
OVX
C3
22nF
+
C21
Close toIC
680pF
C2
22nF
1
2
3
C11
4
220nF 5
6
7
220K 8
0
9
10
11
12
56K
13
VA+
14
VA15
EXTSRC 16
17
18
19
20
21
22
23
24
25
C1
Metallized Polypropylene Film Capacitor : C7
Metallized Polyester Capacitor : C1 , C13 , C11 , C29
0
V + ZR2
V1R15
5.6V
Regulator DC3.0V
10uF
ZR1
C16
0.1uF
220nF
7.5V
C9
470nF
R23
R18
R19
R20
R21
R22
VR2 50K
1K
180K
R11
C10
C12
4.7uF
C6
VR1
500
R2
11K
+
D
C18
0.1uF
10uF
C28
C17
220pF
C30
+
JP2
1
2
VIN
Insulation R+
SW1
SW_RC
R24
OVH1
3
2.2uF
C24
R17
R14 2.2K PTC
1K
Q8
Q7
R25
Q5
R16 2.2K PTC
Q6
2
ACVH
ADI
C
B
A
1
470nF +/- 10%
C8
OPINOPIN+
OPout
R6
R7
R8
IVSH 100K
IVSL 100K
ADP 100K
Close to IC
Close to IC
100
C4
10nF
99
98
97
96
95
94
93
VCC
92
91
90
LBAT9
89
C5
470nF
88
87
SDA
86
SCL
85
84 DATA_new
83
82 BUZOUT
VSS
81
CS
80
79
78
77
76
CIH
CHCH+
AGND
AGND
DGND
V+
V+
uPVCC
VVLBAT
CC+
SDATA
SCLK
DATA_new
NC
BZOUT
IO_CTRL
CS
OSC1
OSC2
NC
NC
OVX
OVH
OVH1
NC
NC
NC
NC
NC
NC
NC
SGND
IVSH
IVSL
ADP
OPINOPIN+
OPOUT
ACVL
ACVH
ADI
ADO
TEST5
CACA+
OHMC4
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
D
C
B
A
12/01/12
25
ver. 2.8
+
ES51970(6000counts)
DMM Analog front end with Inrush
3. Application Circuit
3.1 RMS circuit (ES636)
ES51970(6000counts)
DMM Analog front end with Inrush
4. Package Information
4.1 100L LQFP Outline drawing
4.2 Dimension parameters
ver. 2.8
26
12/01/12