NJU9214 [NJRC]
4.3/4 DIGIT SINGLE CHIP DIGITAL MULTIMETER LSI; 4.3 / 4位单芯片数字万用表LSI
| 型号： | NJU9214 |
| 厂家： | 
NEW JAPAN RADIO |
| 描述： | 4.3/4 DIGIT SINGLE CHIP DIGITAL MULTIMETER LSI |
| 文件： | 总29页 (文件大小：578K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
NJU9214
PRELIMINARY
4•3/4 DIGIT SINGLE CHIP DIGITAL MULTIMETER LSI
!GENERAL DESCRIPTION
PACKAGE OUTLINE
The NJU9214 is a 4•3/4 digits single chip digital multimeter LSI with
42 segments bargraph display.
The NJU9214 realizes high precision of ±40,000 counts measure-
ment by the NJRC original dual-slope A to D converter and realizes
also quick response bargragh display and auto-ranging by another high
speed dual-slope A to D converter.
NJU9214FG1
The input attenuator part is simplified because the resistor for resis-
tance measurement is applied for voltage bleeder resistor.
Furthermore, the NJU9214 realizes root-mean-square measurement
for AC voltage and current by connecting a External RMS-DC Con-
verter, and Data output by the on chip RS-232C interface circuit.
The NJU9214 is suitable for high precision and high performance
multimeter.
!FEATURES
• 4•3/4 Digit Display (Available for UP to ±39,999 Display)
• 42 Segments Quick Response Bargraph Display
• NJRC Original Dual-Slope A to D Converter (±40,000Counts)
• High Speed Dual-Slope A to D Converter (±400Counts)
• Quick Response Auto-Ranging (20times/sec)
• Frequency/Capacitance/Tachometer/Adapter Measurement
• Root-Mean-Square Measurement by connecting a External RMS-DC Converter
• External Relay Driving
• Data Memory/Data Hold/Relative Display/MAX, MIN Display
• Power-on Initializing
• Auto Power-off
• Buttery Life Detector
• Rotary/Push SW Mode Selection
• 1/4 Duty LCD Display Driver
• Piezo Buzzer Direct Driving
• RS-232C Interface
• External Reference Input required
• Low Operating Current
• C-MOS Technology
• Package Outline TQFP100
NJU9214
!BLOCK DIAGRAM
REGURATOR
REFERENCE
A
VDDA AGND VSSA
VDDD VSSD
+5.0V 0V -5.0V
5.0V
0V
IVSL, IVSH
VI,
VR2 to 7,
OVH,
BATT
DCV, ACV,
REFERENCE
BUFFER
LOW
Ω,
,
,CAP,
DCmA, ACmA,
FRQ, rpm
DETECTOR
OVX
ANALOG
ADP
SECTION
FRQ
BUFFER
HIGH
HIGH
CAPACITOR
COM
A/D SECTION
SPEED
RESOLUTION
SGND
A/D SECTION A/D SECTION
RMSIN
SWITCH
HIGH SPEED
HIGH RESOLUTION A/D I/F
NETWORK I/F
A/D I/F
DIGITAL
SECTION
RELAY
CONT-
ROLER
SWITCH
HIGH SPEED
POWER ON
HIGH RESOLUTION
RD1 to 4
A/D CONTROLER
INITIALIZE
NETWORK
CONTROLER
A/D CONTROLER
4bitBUS
FC1 to 4,
KI1 to 5
LCD
CONTROLER
KEY
RS232C
BUZZER
4bit CPU
TEST
OSC
CONTROLE
CONTROLER
CONTROLER
TRX
TXS
RST
PON
LCD DRIVER and POWER
COM1 to 4
SEG1 to 28
BZ
T1 to T3
XT1
XT2
KEY MATRIX
RS232C
DRIVER
BUZZER
LCD
NJU9214
!PIN CONFIGURATION
75
70
65
60
55
SEG16
SEG15
SEG14
SEG13
SEG12
SEG11
50
BUF
CL2
CH2
VREF3
VREF2
VREF1
80
85
45
40
35
SEG10
SEG9
SEG8
CH1
CL1
INT1
SEG7
INT2
SEG6
SEG5
SEG4
SGND2
SGND1
AGND
NJU9214FG1
SEG3
SEG2
SEG1
COM4
COM3
CMO2
COM1
T3
IVSH
IVSL
ADP
OVX
OVH
VR7
VR6
VR5
VR4
VR3
VR2
V1
90
95
30
T2
T1
RST
PON
100
1
5
10
15
20
25
!TERMINAL DESCRIPTION
No.
SYMBOL
ACOUT
VDDA
I/O
Out
-
FUNCTION
1
Attenuator output terminal (used at ACA, ACmA, FRQ, rpm)
Analog VDD (VDDA = 5.0 ± 0.25V)
2
3
4
RMSIN
In
RMS-Voltage Input Terminal
VDDD
-
Digital VDD (VDDD = 5.0 ± 0.25V)
5 to 8
9
RD1 to RD4
TXS
Out
In
Relay Driving Terminal
RS232C Output-Rate Select Terminal L ; 9600bps H ; 2400bps
RS232C Function Select Terminal
10
TRX
In
11
KMS
In
Key Mode Select Terminal
12
RMS
In
Range Control Mode Select Terminal
13 to 20
17 to 20
21 to 25
RC0 to RC3
FC1 to FC4
KI1 to KI5
In
Range Select Terminal with Input Pull-up Resistance (300kΩ)
Function Select Terminal with Input Pull-up Resistance (300kΩ)
Optional Function Control Terminal with Input Pull-up Resistance (300kΩ)
I/O
In
NJU9214
No.
26
SYMBOL
PON
I/O
In
F U N C T I O N
Auto Power-off Mode Release Terminal with Input Pull-up Resistance (300Ωk)
System Reset Terminal with Input Pull-up Resistance(10kΩ)
Test Terminal with Input Pull-up Resistance (300kΩ)
27
RST
In
28 to 30
T1 to T3
In
31 to 34 COM1 to COM4 Out LCD Common Terminal
35 to 62 SEG1 to SEG28 Out LCD Segment Terminal
63
64
65
66
67
68
DSR
DTR
TXD
BZ
In
RS232C Data Set Ready Terminal
Out RS232C Data-Terminal Terminal
Out RS232C Data Output Terminal
Out Piezo Buzzer Driving Terminal
Out Crystal oscillation Inverter (Output)
XT2
XT1
In
I/0
-
Crystal oscillation Inverter (Input)
LCD driving voltage I/O Terminal
Opened : VDSP=(VDDD-VSSD) X 3/5
Connected to VSSD : VDSP=(VDDD-VSSD)
69
VDSP
70
71
VSSD
SLEEP
VSSA
Digital VSS VSSD=0V
Out Auto Power-off signal Terminal (Power-off:"H" Level)
72
-
Analog VSS VSSA=-5.0V
73
BLD
In
Buttery Life Detector Terminal, Detection: BLD<4.0V
74,75
76
CIF2, CIF1
BUF
I/0 High-speed integration capacitor connecting Terminal
Out High-speed integrator buffer output Terminal
77,78
CL2, CH2
I/0 High-speed integrator reference capacitor connecting Terminal
VREF1:High-accurate integrator reference voltage input Terminal
VREF3
to
VREF1
VREF2:High-speed integrator reference voltage input Terminal
VREF3:Capacitance measurement integrator reference voltage
79 to 81
In
input Terminal
High-accurate integrator Reference capacitor connecting Terminal
CL1;"-",CH1;"+"
82,83
84,85
CH1, CL1
INT1, INT2
I/0
I/0 High-accurate integrator capacitor connecting Terminal
86,87 SGND2, SGND1
In
-
Analog sensing Terminal
88
89
90
91
92
93
94
95
96
97
98
99
100
AGND
IVSH
IVSL
ADP
OVX
OVH
VR7
VR6
VR5
VR4
VR3
VR2
VI
Analog GND Terminal
In
In
In
In
Current measurement (A) sensing Terminal
Current measurement (mA) sensing Terminal
Adapter input Terminal
Sensing Terminal (Resistance,Continuity,Capacitance)
Out Voltage supply Termina l(Resistance,Continuity,Diode,Capacitance)
I/0 Bleeder Resistance Terminal for 4V,40V range
I/0 Bleeder Resistance Terminal for 400Ω renge
I/0 Bleeder Resistance Terminal for 4000V,4kΩ renge
I/0 Bleeder Resistance Terminal for 400V,40kΩ renge
I/0 Bleeder Resistance Terminal for 40V,400kΩ renge
I/0 Bleeder Resistance Terminal for 4V,4000kΩ renge
In
Voltage input Terminal for 400mV range
NJU9214
!FUNCTION DESCRIPTION
( 1 )Measurement function
Each measurement functions shown below is available with the NJU9214.
MEASUREMENT
RANGE
Auto/Manual
FUNCTION
DC/AC Voltage
400mV to 4000V
4mA to 4000mA
40A
Auto:4-range/Manual:5-range
*1
*2
DC/AC Current
DC/AC Current
Resistance (Ω)
Frequency (f)
Auto·Manual-2range/Manual-4range
Fixed
400Ω to 40MΩ
100Hz to 1000kHz
4nF to 400µF
Auto:6-range/Manual:6-range
Auto:5-range
Capacitance (C)
Tacho (rpm)
Auto:6-range/Manual:6-range
6000rpm to 600Krpm
Auto:3-range
Fixed
Diode(
)
Continuity(
ADP
)
Fixed
Fixed
*3
*1 400mV range (AC/DC) is selected in only manual range.
*2 4mA-4000mA range has Auto/Manual-2range and Manual-4range mode, each mode
needs its own application circuit.
*3 ADP is applied for ºC, hfe and other measurement.
( 1 - 1 ) Voltage (DCV, ACV) measurements
The divided voltages which are output from each resistance R1 to R5 shown in following table are supplied to A/
D converter.
In the AC measurement, after the dividing voltage, these output voltages are converted to DC Voltages with the
external RMS/DC converter. This DC voltage is supplied into A/D converter.
10MΩ resistor for input terminal may be easy to be affected by noises.
Therefore 10MΩ and peripheral circuits require some protection like shields and so on for stable display.
The resistors for attenuating should be selected with a flat temperature characteristic. Especially, the resistors
(10MΩ, 10kΩ, 1kΩ) for 400V, 4000V ranges should be selected carefully. For example, when 4,000V is input,
0.4mA (4,000V÷10MΩ) flow through 10MΩ, and the resistor consumes power of 1.6W (4,000V×0.4mA) and the
temperature of the reference resistor.
After measuring at 400V, 4,000V ranges, sometimes the uncorrect value is shown on the display at 4V, 40V
ranges because the value of resister as the attenuator is changed by the temperature.
RANGE
R1(400mV)
R2(4V)
DIVISION RATE
1
1MΩ/10MΩ
100kΩ /10MΩ
10KΩ /10MΩ
1kΩ/10MΩ
R3(40V)
R4(400V)
R5(4000V)
NJU9214
( 1 - 2 ) Resistance measurement(Ω)
As shown below, six type resistors ( 10MΩ,1MΩ,100kΩ,10kΩ,1kΩ,100Ω ) connecting VR2 to VR7 are used for
reference resistors of each range.
The output voltage on the measurement terminal is almost same as the voltage inputted Vref3.
As shown in Application circuits (1) to (3), an input protective diode must be connected with the OVH terminal.
In resistance measurement, continuity test, diode check and capacitance mode, if the NJU9214 is supplied high
voltage on the OVH terminal from the external, the NJU9214 may be broken completely.
In the R1 (400Ω) range, sometimes the resistor value shows wrong display because of the influence by test
leads and wiring resistances of a circuit board. In this case, it needs to adjust on the relative function using the 0
Ω resistance.
In the R6 (40MΩ) range, it may take a time to get the correct measurement value by the influence of parasitic
capacitance and may not show the stable value by the noise effects.
RANGE
R1(400Ω)
R2(4KΩ)
Refer.Resistance Value
100Ω
1kΩ
R3(40KΩ)
R4(400KΩ)
R5(4000KΩ)
R6(40KΩ)
10kΩ
100kΩ
1MΩ
10MΩ
( 1 - 3 ) Continuity test(
)
The input attenuator is fixed to 400Ω range of the resistance measurement mode. When the value is less than
40Ω, the buzzer sounds. The output voltage on the measurement terminal is about 0.4V.
If the display doesn't show 0Ω by resistances of lead wire when the terminals are shorted,
this case requires adjustment at 0Ω using the relative function.
( 1 - 4 ) Diode check(
)
The input attenuator is fixed to DC4V range. The output voltage on the OVH terminal is about 5V (VDDA), and it
is supplied to the measurement terminal through the SW1 (external switch or relay).
( 1 - 5 ) Current ( DCmA, ACmA ) measurement
Current measurement provides the Auto-Manual 2-range mode(RMS=H) and the Manual 4-range mode (RMS=L).
These are changed by status of the RMS terminal. Each mode needs its own application circuit.
In the Auto-manual 2-range mode, the sense terminal is IVSL terminal at the 40mA range and IVSH terminal at
the 400mA range.
In the Manual 4-range mode, the sense terminal is IVSL. In this mode, switching range is performed by changing
the reference resistors. The SW for the reference resistor change must be operated together with the SWs
connecting to ' RC1 to RC3 '. ( Refer to ( 2 - 1 - 3 ) )
( 1 - 6 ) Current ( DCA, ACA ) measurement
It is fixed to the 40A range. The sense terminal is the IVSH terminal.
NJU9214
( 1 - 7 ) Frequency ( f ) measurement
The input voltage is divided by the attenuator, and then the attenuator output is supplied to counter through the
buffer.
The divided voltage is converted to DC voltage by the external RMS/DC converter, and the dividing voltage ratio of
the input attenuator is changed by this DC voltage, Noises or distorted waveforms sometimes show different
display against actual frequency.
The frequency range is always fixed to the Auto-range mode. It is able to switch from 100Hz to 1,000kHz and
the measurement cycle is 1 time a second.
( 1 - 8 ) RPM measurement
It is possible to measure numbers of revolution like as the revolutions of engine. The measurement is same way
as the frequency measurement. The revolutions are calculated by the value of 60 times the frequency.
The revolution range is always selected one of 6,000 to 600krpm automatically.
The minimum input voltage ( wave amplitude ) is about 300mV and the measurement cycle is 1 time a second.
( 1 - 9 ) Capacitance ( C ) measurement
The constant-current charges the measured capacitor, and the charging time, while the voltage of capacitance
reaches to the reference voltage, is measured and converted to the capacitance value.
If the measured capacitor has any electric charges, accurate measurement is not available. Therefore the
measured capacitor must be discharged before measurement.
The sense terminal is the OVX terminal.
( 1 - 10 ) Adapter ( ADP ) measurement
The voltage between the ADP terminal and the SGND is supplied to the A/D converter directly. Both of ADP
terminal ( + ) and SGND terminal ( - ) are High-impedance in DC400mV range.
Therefore, it is also used as differential input.
( 2 ) Switch input Mode
The lock or push type input switch is applied for function selection. The switch type is selected in both of auto
and manual ranges by the RMS terminal setting.
When the push type switch is selected, auto ranging is always selected.
When the lock type switch is selected and the RMS terminal is GND ( L ) level, all ranges are selected by
switches. But if the RMS terminal is VDD level ( H ), auto range, manual range selection and the range set are
performed by a push type switch.
KMS Terminal
RMS Terminal
SWITCH
Lock type
Push type
RANGE
Full Auto
Manual
H
H
L
H
L
*
Full Auto
* : Don't Care
Both of lock and push type application have the chattering protective function which reject the chattering less
than 20ms.
NJU9214
( 2 - 1 ) Lock type switch
( 2 - 1 -1 ) Measurement function selection ( KMS = " H " )
The measurement function is set by FC1 to FC4 terminal. Excepting the following settings, all others select the
DCV measurement mode.
Measurement mode
FC1
H
L
FC2
H
H
L
FC3
H
H
H
H
L
FC4
H
H
H
H
H
H
H
H
L
D
A
D
A
C
C
C
C
V
V
mA
mA
H
L
L
Resistance ( Ω )
H
L
H
H
L
Continuity (
Diode (
)
L
)
H
L
L
Capacitance ( C )
L
L
D
A
C
C
A
A
H
L
H
H
L
H
H
H
H
L
L
Frequency ( f )
r p m
H
L
L
L
L
A
D
P
H
H
L
( 2 - 1 - 2 ) Range setting ( Lock type & Auto-Ranging : KMS = RMS = " H " )
The range shown in below table is controlled by a switch of the RC0 terminal which must go to "L" level ( GND )
when it is pressed. When the switch is pressed once, the range is changed from Auto-range to manual-range,
and its range is held. Then, the range is changed in every time by the switch operation. The range always returns
to Auto-range from any kinds of range when the switch is pressed over than 1 second.
1push(>1sec)
Auto
1push(<1sec)
Default
Measurement Mode
Ranging control
Manual
Range up
Range
1push(<1sec)
D
A
D
A
C
C
C
C
V
V
R2 to R5
R2 to R5
R2 to R3
R2 to R3
R1 to R6
(R5→R2)
(R5→R2)
4V to 4000V
4V to 4000V
4V
4V
mA
mA
Ri→ Ri+1 (R3→R2)
(R3→R2)
40mA to 400mA
40mA to 400mA
400Ω to 40MΩ
40mA
40mA
400Ω
400Ω
4V
→ H O L D
Resistance ( Ω )
(R6→R1)
Continuity (
Diode (
)
)
A
D
A
D
C
C
P
A
A
F I X E D
400mV
40A
40A
Frequency ( f )
Tacho ( r p m )
R1 to R5
R1 to R3
R1 to R6
100Hz to 999.9kHz
6000rpm to 600krpm
4nF to 400uF
100Hz
6000rpm
4nF
Auto-range
Capacitance ( C )
Ri→Ri+1 (R6→R1)
→H O L D
NJU9214
( Note ) Frequency measurement and revolution measurement are always set to the Auto-Range.
Ranges of continuity test ( ), diode check ( ), ADP, DCA and ACA measurement are always fixed to the
default ranges. Just after the power-on operation or mode changing, the range is set to the default range.
In the ADP measurement, three units are displayed by setting of RC1 to RC3 terminals.
The R1 to R6 of above range control table are set as a range corresponding to below table.
RANGE D C V
A C V D C mA A C mA
f
r p m
*6000
60000
600k
C
Ω
R1
R2
R3
R4
R5
R6
400mV 400mA
*400Ω
4kΩ
*100Hz
1000Hz
10kHz
100kHz
*4nF
40nF
400nF
4uF
*4V
40V
*4V
40V
*40mA *40mA
400mA 400mA
40kΩ
400kΩ
400V
400V
4000V 4000V
4000kΩ 1000kHz
40MΩ
40uF
400uF
(NOTE) The " * " mark means the default range.
Changing to DC400mA range or AC400mA is available by only manual operation. Auto-range operation cannot
change to these ranges.
( 2 - 1 - 3 ) Range setting ( Lock type switch & Manual-range : KMS = " H ", RMS = " L " )
The range setting shown in below table is available with RC1 to RC3 terminal.
RC1
H
L
RC2
H
H
L
RC3
H
H
H
H
L
DCV, ACV DCmA, ACmA
C
Ω
400mA
4V
4mA
40mA
400mA
4000mA
4mA
400Ω
4kΩ
4nF
40nF
400nF
4uF
H
L
40V
40kΩ
400kΩ
4000kΩ
40MΩ
400Ω
400Ω
L
400V
H
L
H
H
L
4000V
400mV
400mV
400mV
40uF
400uF
4nF
L
4mA
H
L
L
4mA
L
L
4mA
4nF
( NOTE ) Frequency and revolution measurements are always set to the Auto-range.
Ranges of continuity test ( ), diode check ( ), ADP, DCA and ACA measurement are always fixed to the
default ranges.
NJU9214
( 2 - 2 ) Push type switch
( 2 - 2 - 1 ) Measurement function selection ( KMS = " L ", ARMS = " X " )
Measurement function is set to the mode depending on the below matrix table;
Control Terminals
KI1
KI2
HOLD
FRQ
DC/AC
V
KI3
MIN/MAX
ADP
KI4
MEN
REL
KI5
FC1
FC2
FC3
FC4
Don't care
Don't care
Don't care
rpm
READ
CAP
Selection
Terminals
Ω
mA
A
RANGE
All switches excepting for the power switch should be used non-locked push type switch.
The range is set to the full auto-range mode and selected by the "RANGE" key.
When the power is turned on, the mode is set to the DCV. When the auto power-off is released, the mode
returns to the previous mode of auto power-off.
The functions of HOLD, MIN/MAX, MEM, READ and REL are same as KI1 to KI5 input using lock type
switch which is explained in ( 4 ) Attached functions.
If some of switches are pressed at the same time, the input order is as follows,
Selection terminal : FC4→FC3→FC2→FC1
Control terminal : KI5 → KI4 → KI3 → KI2 → KI1
< Example of the switch circuit >
N J U 9 2 1 4
rpm
V
mA
A
RANGE
VSSD
DC/AC
Ω
FRQ
ADP
REL
CAP
HOLD
MEM
READ
MIN/MAX
NJU9214
Range setting ( Push type switch : KMS = " L ", RMS = " X " )
The range setting shown in below table is available with the " RANGE " switch.
When the switch is pressed once, the range is changed from auto to manual, and it’s range is held.
Then, the range is changed in everytime by the switch operation. When the switch is pressed over
than 1 second, the range always returns to Auto-range is possible from any range statuses.
1push(>1sec)
Default
Range
Auto
Range up
Manual
Measurement Mode
Ranging Control
1push(<1sec)
1push(<1sec)
D
D
D
D
C
C
C
C
V
R1 to R5
R1 to R5
R2 to R3
R2 to R3
R1 to R6
(R5→R1)
(R5→R1)
400mV to 4000V
400mV to 4000V
40mA to 400mA
40mA to 400mA
400Ω to 40MΩ
4V
4V
V
mA
mA
Ri→ Ri+1 (R3 →R2)
(R3→R2)
40mA
40mA
400Ω
400Ω
4V
→ HOLD
Resistance ( Ω )
(R6→R1)
Continuity (
Diode (
)
)
A
D
A
D
C
C
P
F I X E D
400mV
40A
A
A
40A
Frequency ( f )
Tacho ( r p m )
Capacitance ( C )
R1 to R5
R1 to R3
R1 to R6
100Hz to 999.9kHz
100Hz
Auto-range
6000rpm to
600krpm
6000rpm
4nF
Ri→Ri+1 (R6→R1)
4nF to 400uF
→ HOLD
( NOTE ) Frequency measurement and Tacho are always set to the auto-range.
Ranges of continuity test ( ), diode check ( ), ADP, DCA and ACA measurements are
always fixed to their default ranges.
Just after power-on operation or changing mode, their ranges are set to the default range.
In the ADP measurement, 3 units are displayed by setting of RC1 to RC3 terminals.
The R
1
to R of above range control table are set a range corresponding to below table.
6
RANGE
R1
DCV
ACV
400mA
*4V
DCmA
ACmA
f
r p m
C
Ω
400mV
*4V
-
-
*400Ω
4kΩ
*100Hz
1000Hz
10kHz
100kHz
*6000
*4nF
40nF
400nF
4uF
R2
*40mA
*40mA
60000
R3
40V
40V
400mA
400mA
40kΩ
400kΩ
600k
R4
400V
4000V
-
400V
4000V
-
-
-
-
-
-
-
-
-
-
R5
4000kΩ 1000kHz
40MΩ
40uF
400uF
R6
-
( NOTE ) The " * " mark means the default range.
Changing to DC400mV range or AC400mV range is available by only manual operation. Auto-range
operation cannot change to these ranges.
When the auto-range is switched in DC400mV or AC400mV range, measurement is continued in the
400mV range. When overflow occurs in 400mV of the auto-range, its range changes to 4V range auto-
matically.
NJU9214
< Example of the Latching Relay Driver Circuit >
RD1 to RD4 are normally " H ". ( Active " L " )
GND
COM
10A
SGND2
SGND1
AGND
IVSH
33k
33k
IVSL
ADP
OVX
SW1
,
Ω,CAP
100kΩ
PTC 500Ω
,
OVH
OR2
100
1k
OR1
SW5
VR5
VR4
SW2
DCmA,
ACmA
10k
100k
1M
0.1uF
DCV, ACV ,
ACV,ACmA,
FRQ,rpm
, Ω, CAP,
VR3
DCmA, ACmA,
FRQ, rpm, ADP
0.022uF
others
VR2
SW7
DC400mV,ADP
10M
others
SW3
VI
100k
ACOUT
RMSIN
VDDA
VSSA
SW7
RD1RD2RD3 RD4
Rectifier circuit
block
RMS-DC Converter
Power source SW
SW Changing coil of latching relay
VDDD
1kΩ X 14
RESET
VDDD
SET
SW1
SW2
SW3
SW4
VSSD
74HC138
74HC138
SW4 is used into
the rectifier circuit
block shown in the
Example of application
circuit.
SW5
SW8
SW7
VDDD
VDDD
VSSD
NJU9214
About 10ms pulse width signal shown in below table is outputted from RD1 to RD4. This pulse controls the
Latching Relay Driving.
FUNCTION RANGE
, AP
Relay
SW1
RD1
RD2
RD3
RD4
Ω,
,
DCmA, ACmA
DC400mV, ADP
AC400mV
SW2
SW3
SW4
SW5
SW6
SW7
SW1
SW2
SW3
SW4
SW5
SW6
SW7
Set
Set
Ω,
ACA
ACmA,ACA,ACV,FRQ,rpm
Ω,
,
, CAP
DCmA, ADP
DC400mA, ADP
AC400mV
Reset
Reset
Ω,
ACA
ACmA,ACA,ACV,FRQ,rpm
( 4 ) Attached functions ( Functions with KI1 to KI5 are available by only lock type switches. )
( 4 - 1 ) Data Hold : HOLD
The hold or release of all display data is performed alternately by KI1 terminal input.
However, A/D conversion is operating even though in the HOLD status, therefore the buzzer sounds at the over-
range and the continuity test.
In the auto-range operation, changing of range is available.
( 4 - 2 ) Relative Measurement : FREL
The relative measurement is selected when the switch connecting to KI2 terminal is pressed. In this mode, the
value of difference between the present and the just before value is displayed.
In case of the auto-range, the range is held at the just before range.
However, the bargraph displays the absolute value, not the relative value.
And the over-range also occurs from the absolute value of input. When the KI2 is pressed over than 1 second,
the relative mode is released.
( 4 - 3 ) Min. / Max. Hold : MIN/MAX
When the switch connecting to terminal KI3 is pressed, the mode is circulated as follows ;
MIN Value Hold → MAX Value Hold → HOLD Release
The bargraph always displays the input value.
( 4 - 4 ) Data Memory : MEN
When the switch connecting to terminal KI4 is pressed, all of display data is stored into the memory.
The stored data can be read out and displayed on LCD by pressing the READ key connecting to terminal KI5,
and [MEM] mark blinks during this mode.
This mode is released by pressing the READ key connecting to terminal KI5.
NJU9214
( 4 - 5 ) Buzzer output
2kHz buzzer sounds at following cases ;
[ 1 ] Key operation ( except function changing and range changing )
[ 2 ] Auto-power off operation
[ 3 ] Continuity test ( ) ; less than 40Ω
[ 4 ] Releasing from relative mode and MIN / MAX display
[ 5 ] Changed between manual-range and auto-range by RCO terminal
[ 6 ] Auto-range: Overflowing at 4,000V range
Manual-range: Overflowing at every range except 400mV range
[ 7 ] Power-on operating and Releasing from the Auto-power off mode
[ 8 ] Twice sounds from 24 seconds before and every 8 seconds
( 4 - 6 ) Low-Battery Detector : BLD
If the supply voltage is less than 4.0 ± 0.4V, [ BATT ] mark is blinked.
( 4 - 7 ) Auto power-off
If the key-operation doesn't work over than 30 minutes, the power is turned off automatically after 1 second
buzzer sound, and all display is disappeared. ( the data in the memory is kept )
When the PON terminal is pressed or power switch is turned off, this mode is released.
In case of release by PON terminal, the previous value of the auto power-off operation is displayed for 2 sec-
onds. To void this function, the power should be turned on with pressing the switch connecting to the PON
terminal.
The NJU9214 gets some voltage surges during the power off mode by the auto power off operation, it might not
return to usual operation correctly.
( 4 - 8 ) Setting the mode at Power-on, Function and Range changing
FUNCTIONS
Range(Auto range)
Range Hold
Power-on
Function changing
Default range
Range changing
-
Default range
Hold
Data Hold
Reset
Reset
Relative Measure
MIN / MAX Hold
Data Memory
Auto power-off
Reset
All " 0 " display
Auto off
Hold
Hold
Auto off
Auto off
( 4 - 9 ) Display of ADP setting
In measurement operation by the ADP function, the following display setting by RC1 to RC3 terminals is avail-
able.
NJU9214
RC1
H
L
RC2
H
H
L
RC3
H
H
H
H
L
Mark Display Decimal Point
Application Example
Non
Non
hfe Measurement
ADP1
P1
P1
*
°C ( Temp. Measurement )
H
L
ADP2
F ( Temp. Measurement )
L
*
*
*
*
*
*
H
L
H
H
L
*
*
L
*
*
H
L
L
*
*
L
L
*
*
* : ( Don't Care )
( 5 ) Serial Data output
The NJU9214 has terminals (TXD,DTR,DSR) for serial data output with RS-232C format requiring a external RS-
232C I/F LSI.
When the TRX terminal is " L " level, data transmission is available, and when DSR terminal is also " L " level,
the data starts to output.
It selects the transmission rate by the TXS terminal, "L" level : 9,600bps,
"H" level : 2,400bps.
The logic levels from all of output terminals are " L " ≤ 0.8V, " H " ≤ 4.2V.
( 5 - 1 ) The structure of the serial data
An unit of serial data consists of 10bits. The first bit of data is Start bit, the 2nd to the 9th bits are Data bits, the
10th is Stop bits, therefore 11bits data structures a character as an unit.
The data is transmitted from the LSB in sequence. Regarding the data order, please refer to [ ( 5 - 3 ) RS-232C
Data Format ].
The data is outputted with the ASCII code.
( 5 - 2 ) Example of transmission waveform
Example of transmission waveform on the TXD terminal is shown below.
8 bit data
8 bit data
D0 D1 D2 D3 D4 D5 D6 D7
D0 D1 D2 D3 D4 D5 D6 D7
0 1 0 0 1 1 1 0 0 1 0 1 0 1 1 1 0 0 0 1
DATA 1D(HEX)
DATA 39(HEX)
1 Character
1 Character
NJU9214
( 5 - 3 ) RS-232C Data format
As shown below table, the data transmitted through the RS-232C is structured with 1 frame consisting of 17
characters.
( Example ) DCV measurement value = 100mV
D C V .,A = + 100.01 m ,
[CR]
BLD
Unit
Data
Sign
Measurement Mode
FUNCTION
( 5 - 3 - 1 ) Function
FUNCTION
DCV
CHARACTER
D C V
A C V
D C A
A C A
O H M
C H K
D I O
C A P
F R Q
ACV
DCA
ACA
RESISTANCE
Continuity
Diode
Capacitance
Frequency
Tacho
r
p m
ADP
A D P
( 5 - 3 - 2 ) Measurement Mode
Measurement Mode
Absolute Value
Relative Value
Character
A
R
( 5 - 3 - 3 ) Sign
This sign shows the polarity of data.
Sign
Character
+ (PLUS)
- (MINUS)
Positive Number
Negative Number
( 5 - 3 - 4 ) DATA
The data consists of six figures including a decimal point.
NJU9214
( 5 - 3 - 5 ) Unit
This unit name shows the following characters.
Unit Name
Mega-
Kilo-
Character
M
K
-
(Space)
Milli-
m
Micro-
Nano-
µ
n
( 5 - 3 -6 ) Buttery Life Detector
It shows the condition of buttery.
Condition
Normal
Character
(Space)
Low-Buttery warning
B
( 5 - 3 - 7 ) Examples of various data
[ Ex.1 ] In DCV400mV range, when following voltage is measured.
Measured value 100.01mV
Format Pattern
DCV, A=+100.01m,
[CR]
The actual data from RS-232C line is shown below.
ASCII CODE
HEX CODE
D
C
V
,
&H44
&H43
&H52
&H2C
• • •
RS-232C DATA 00010001011 01100001011 00100101011 00011010011
0
1
m
,
[CR]
• • •
&H30
&H31
&H6D
&H2C
&H20
&H0D
00000110011 0100011011 01011011011 00011010011 00000010011 01011000011
[ Ex.2 ] On the condition of Ex.1, when relative mode is used.
To calculate the relative value, the reference voltage must be required. The reference voltage is the
measured voltage of relative mode.
Example of the reference voltage = 100.00mV.
measured value 100.01mV
relative value
100.01mV - 100.00mV = 0.01mV
Format pattern
DCV, R=+000.01m, [CR]
NJU9214
[ Ex.3 ] In DCV400mV range, when overflow is occurred on the positive voltage side by 401mV input.
Measured value
Format pattern
overflow on the "+" side
DCV, A=+
.
m, [CR]
"
.
" shows overflow, "+" shows overflow on the positive side.
[ Ex.4 ] In DCV400mV range, when overflow is occurred on the negative voltage side by -401mV input.
Measured value
Format pattern
overflow on the "-" side
DCV, A=-
"
.
m, [CR]
.
" shows overflow, "-" shows overflow on the negative side.
[ Ex.5 ] In DCV400mV range, when the battery life detector warns under the condition of Ex.1.
Measured value
100.01mV
Format pattern
DCV, A=+100.01m, B[CR]
Battery life detector
[ Ex.6 ] In ACA400mA range, when the following current is measured.
Measured value
Format pattern
40.00mA
ACA, A=+040.00m, [CR]
[ Ex.7 ] In resistance 400kΩ range, when the following resistance is measured.
Measured value
100.10kΩ
Format pattern
OHM, A=+100.10k, [CR]
[ Ex.8 ] In frequency 10kHz range, when the following frequency is measured.
Measured value
5.35kHz
Format pattern
FRQ, A=+005.35k, [CR]
[ Ex.9 ] In tachometer 6000rpm range, the following revolution is measured.
Measured value
2500rpm
Format pattern
rpm, A=+02500 , [CR]
NJU9214
( 6 ) Reference voltage
The resolution of NJU9214 is 25ppm ( 1/40000 ), and high precision is required for the reference power supply.
The reference voltage requires a high precision and a temperature compensated type like as a band-gap refer-
ence.
Reference voltages, VREF1 and VREF2 are about 0.2V, and VREF3 is about 2V.
( 7 ) Example of Display Layout
( 7 - 1 ) Connection of Common Line
BATT
REL
HOLD
MAX
MIN
MEN
APF
A C
F
C
COM4
D C
µ m V A
n F r p m
M K Ω H z
RS232C
AUTO
COM3
COM2
COM1
0
10
20
30
40
( 7 - 2 ) Connection of Segment Line
BATT
A C
REL
HOLD
MAX
MIN
MEN
APF
F
C
D C
µ m V
A
n F r p m
M k Ω Hz
RS232C
AUTO
0
10
20
30
40
( 7 - 3 ) Segment Assignment
SEG1 SEG2 SEG3 SEG4 SEG5 SEG6 SEG7
SEG8
PB13
BP12
e3
SEG9 SEG10
BP14 BP16
COM1
COM2
COM3
COM4
BPN
BP0
BP-
DC
BP2
BP1
-
BP4
BP3
AUTO
AC
BP6
BP5
e4
BP7
d4
BP9
BP8
c4
PB11
BP10
P4
d3
g3
a3
BP15
c3
g4
BATT
f4
a4
b4
REL
f3
b3
SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20
COM1 BP18 BP20
COM2 BP17 BP19
BP21 BP23 BP25 BP27 BP28
BP30
BP29
c1
BP32 BP34
BP31 BP33
d2
g2
a2
BP22 BP24 BP26
d1
g1
a1
COM3
P3
e2
f2
c2
b2
P2
e1
f1
P1
e0
COM4 HOLD
MAX
b1
MIN
f0
/
SEG21 SEG22 SEG23 SEG24 SEG25 SEG26 SEG27 SEG28
/
/
/
/
/
COM1 BP35 BP37 BP39 BP40
M
F
k
rpm
F
Hz
Ω
RS232C
/
COM2
COM3
COM4
d0
g0
a0
BP36 BP38
n
m
/
/
/
/
c0
b0
V
A
/
µ
MEM
APF
°C
/
NJU9214
a4
b4
a3
a2
a1
a0
b3
b2
b1
g1
b0
g0
f4
f3
f2
f1
f0
g4
g3
g2
e4
c4
e3
c3
e2
c2
e1
c1 e0
c0
d4
p4
d3
p3
d2 p2
d1
p1
d0
BP-
BP0
0
BPN
BP40
40
BPN
10
BPN
20
BPN
30
BPN
( 7 - 4 ) Explanation of Display Mark
1.
2.
3.
4.
BATT : Low-Battery Detecting mark.
DC : Displayed in DC voltage and DC current measurement mode.
AC : Displayed in AC voltage and DC current measurement mode.
-
: Displayed in DC voltage and DC current measurement negative input.
This mark doesn't display in AC voltage, AC current, resistance( Ω ),
frequency ( f ), diode ( ), and capacitance ( C ) and continuity ( ) measurement mode.
5.
6.
7.
8.
9.
AUTO : Displayed in the auto range measurement mode.
REL : Displayed in the relative display measurement mode.
HOLD : Data Hold. Displayed in Memory READ with READ key.
MAX : Displayed in maximum display mode.
MIN : Displayed in minimum display mode.
10. MEM : Displayed during memorizing data. Blinked during recalling the data.
11.
12.
: Displayed in continuity test measurement mode.
: Displayed in diode check measurement mode.
13. mV : Displayed in DCmV and ACmV ranges.
14. mA : Displayed in DCmA and ACmA ranges.
15. °C
16.
: In ADP measurement mode, displayed with ADP1 mark.
F
: In ADP measurement mode, displayed with ADP2 mark.
17. nF
: Displayed in capacitance measurement mode. ( 4nF, 40nF, 400nF ranges )
: Displayed in capacitance measurement mode.( 4µF, 40µF, 400µF ranges )
: Displayed in resistance measurement mode.( 400Ω range )
: Displayed in resistance measurement mode.( k Ω range )
18. µF
19.
Ω
20. kΩ
21. MΩ : Displayed in resistance measurement mode.( MΩ range )
22. Hz : Displayed in frequency measurement mode.( Hz range )
23. kHz : Displayed in frequency measurement mode.( kHz range )
24. rpm : Displayed in tachometer measurement mode.
25. RS-232C : Displayed in available mode of RS-232C Blinking under RS-232C operation.
26. APF : Displayed under Auto Power Off operation. After 30 minutes from the last key
input, the power is turned off automatically.
NJU9214
( 7 - 5 ) Bargraph display
The bargraph displays 10 times speed comparing with numeric display. However it is not displayed in frequency,
revolution and capacitance measurement mode.
1. BP-
: Displayed when negative signal is input.
2. BP0
: Displayed when the digital display is more than about "00400".
: BP1 is displayed when the digital display is more than about
"01000", then 1 segment display increases at every 1,000 counts.
If overflow occurs, all of BP0 to BP40 are displayed.
3. BP1 to 40
4. The figures of " 0, 10, 20, 30, 40 "under the bargraph is displayed expecting for frequency, tacho
and capacitance measurement mode.
( 7 - 6 ) Over-range Display
When the over-range is occurred, the display becomes " 40000 " and all digit blinks.
However " 0000 " is displayed in frequency measurement mode, " 60000 " is displayed in revolution measure-
ment mode, " 4000 " is displayed in capacitance measurement mode, and also every digit blinks in these modes.
In relative measurement mode, but it is not concerned with the display value. All of digits blink when over-range
occurs by the absolute input value.
( 7 - 7 ) Polarity Display
In cases of the “ 0 ” display value, AC voltage, AC current, resistance ( Ω ), diode (
), capacitance ( C ),
frequency ( f ), tacho ( rpm ) and continuity test ( ) measurement mode, " - " mark is not displayed. However in
relative measurement mode, any measurement modes display " - " .
NJU9214
!ABSOLUTE MAXIMUM RATINGS
( Ta=25°C )
PARAMETER
SYMBOL
VDDA - VSSA
VDDD - VSSD
Vid
RATINGS
UNIT
V
Supply Voltage Range
11
5.5
VDDD to VSSD
VDDA to VSSA
50
V
Control Terminal Voltage
Analog Terminal Voltage
V
Via
V
Supply Teminal IDD, IGND, ISS
Terminals
Current
OVH Terminal
Others
IOVH
I I
50
mA
10
Operating Temperature
Topr
Tstg
0 to +50
-40 to +125
°C
°C
Storage Temperature Range
VDDD and VDDA must be same voltage level.
!ELECTRICALCHARACTERISTICS
( 1 )DC Characteristics
( VDD = + 5.0V, VSSA= - 5.0V, AGND = DGND = 0V, DC400mV range, Ta=25°C)
PARAMETER
SYMBOL
VDD
CONDITIONS
MIN TYP
4.75 5.0
MAX
5.25
1.5
UNIT
V
NOTE
1
Operating Voltage
IDD
VDD Terminal
-
-
-
-
mA
mA
V
Operating Current
IPOF
VSS
VDD Terminal,in auto Power off
VDD Terminal
0.01
-5.25
4.4
2
Negative Supply Voltage
-4.75 -5.0
Low-Battery Detection Voltage VBLD VBLD terminal
3.6
4.0
V
Digital Display
Bargraph
Linn
Ling
Epn
Epg
Zero
tsn
-
-
-
-
0
-
-
-
-
-
-
-
-
±0.07+2 %FS±COUNT
±5 %FS
±0.07+2 %FS±COUNT
Linearity
Digital Display
Bargraph
Input Series Resistor = 100k Ω
-
Polarity
Error
-
±5
0
-
%FS
Zero Reading Display
Digital Display
0
COUNT
100
500
5
Sampling
Capacitance M.
Bargraph
tsnc
tsg
-
ms
Time
-
Digital Display
Capacitance M.
Bargraph
Nrn
2
-
Sampling
Rate
Nrnc
Nrg
1
-
cyc./s
20
-
TXS, TRX, FC1 to 4, RC0 to 3,
KI1 to 5, T1 to 3,
High Level Input Voltage
Low Level Input Voltage
VIH
VIL
4.2
-
-
-
-
V
V
0.8
PON, KMS, RMS, RST Terminal
TXS, TRX, FC1 to 4, RC0 to 3,
KI1 to 5, T1 to 3, PON Terminal
100 300
10
500
-
Input Pull-Up Resistance
RI
kΩ
RST Terminal
-
NOTE 1 : VDD is the general term for VDDA and VDDD.
NOTE 2 : In this case, all of key input levels are High.
In case of “LOW” level input into the key, 16uA current flow from a pin through an internal pull up
resistance ( 300kΩTYP. ) in TXS, TRX, KMS, RMS, RC 0 to 3, FC1 to 4, KI1 to 5, PON, T 1 to 3
terminals and 500uA current flow from RST terminal though a pull up resistance ( 10kΩ TYP. ).
NJU9214
DC Characteristic (A/D conversion)
( VDD = +5.0V, VSSA = -5.0V, AGND = DGND = 0V, DC 400mV range, Ta = 25°C)
PARAMETER
SYMBOL
IOH1
IOL1
CONDITIONS
VOH = 4.7V
MIN
TYP
0.75
MAX UNIT NOTE
0.25
-
-
Buzzer Driving Current
BZ Terminal
VOL = 0.3V
VOH = 4.6V
VOH = 0.4V
VOH = 4.6V
VOH = 0.4V
-0.25 -0.75
IOH2
IOL2
0.5
-0.5
0.5
1.0
-1.0
1.0
-
DTR, TXD Terminal
RD1 to 4 Terminal
Digital Output Current
mA
-
IOH3
IOL3
-
-
Select Terminal
Output Current
FC1 to 4 Terminal
(Push Switch Mode)
-0.5
-1.0
Open volltage
VOHM used for Ω,
measurement
-
-
0.4
5
-
in Resistance Measurement
V
Charging Voltage
VCAP used for " C " measurement
-
3
4
in Capacitance Measurement
ILO
ILF
VH
VL
VH
VL
VIN=0mV
VIN=±400mV
-
-
±10
±40
-1.2
-2.2
-1.8
-3.5
Input Leakage Current
VI Terminal
pA
V
-
-
-0.9
-1.8
-1.4
-3.1
-1.0
-2.0
-1.6
-3.3
LCD Driving Voltage
(VDSP is floating.)
SEG1 to 28, COM1 to 4 Terminal
( vs VDDD Voltage )
LCD Driving Voltage
(VDSP and VSSD are shorted.)
NOTE 3 : The current source outputs VDD = 5V as an open voltage, however in normal operation, about 1V as
the threshold of comparator is maximum voltage.
NJU9214
about 1V
0V
Measured capacitor
SW1
SW2
OVX
OVH
SW1
SW2
about 1V
NJU9214
NOTE4 : LCD Diving Voltage ( Example of output waveform )
Waveform of 1/4 Duty, DC400mV range, VIN = 0mV
VDD
COM1
VDSP
VDD
COM2
VDSP
VDD
COM3
VDSP
VDD
COM4
VDSP
VDD
SEG1
VDSP
VDD
SEG2
VDSP
VDD
SEG3
VDSP
VDD
SEG4
VDSP
1 cycle
NOTE5 : Terminals of digital line are protected by the ESD protection circuit, however
terminals of analog line aren't protected enough because the parasitic capacitance
must be decreased. Therefore, if the NJU9214 is given static electricity, it may
be permanent breakdown. Therefore enough external surge protection is needed
for assembling, carrying and keeping.
( 2 ) Switching characteristic
( VDDA = VDDD = +5.0V, VSSA = -5.0V, AGND = DGND = 0V, DC4V range, fXT=4MHz, 25°C)
PARAMETER
SYMBOL
FBZ
CONDITIONS
BZ Terminal
MIN
TYP
2.0
MAX
UNIT
kHz
Buzzer Output Frequency
-
-
-
-
-
-
(TXS:H)
(TXS:L)
2400
9600
Data transmission rate
tOUT TXD terminal
bps
SEG1 to 28,
FLCD
LCD driver frequency
Relay driver pulse width
-
-
50
10
-
-
Hz
COM1 to 4 terminal
twrd
RD1 to 4 terminal
ms
NJU9214
!Examples of application circuit.
( 1 ) Circuit using lock type switch. ( Current Auto • Manual-2 range mode, RMS = " H " )
10A COM
When Ω/
/
/ cap,
Reference Voltage element:over 2.5V
DCV, ACV,
FUSE
SW1 is ON.
,
, Ω, CAP,
Temperature coefficient:below 20ppm/ C
.
When AcmA/DcmA,SW2 is ON
ADP
DCmA, ACmA,
FRQ, rpm
BATTERY
VDDA
SW2
+5V
10K
9
0.99 0.01
AC measurement: AC coupling side
SW1
SW7
0.022uF
DC400mV:VI side
Others:VR2 side
SW5
0.1uF
VSSA
-5V
SW3
VDDD
+5V
Rectification
circuit
block
CIF1
CIF2
BLD
VSSA
SLEEP
VSSD
VDSP
XT1
XT2
BZ
TXD
DTR
ACOUT
100
95
90
85
80
75
1
5
VDDA
VDDD
VDDA
RMSIN
VDDD
RD1
RD2
RD3
RD4
TXS
TRX
KMS
RMS
RC0
RC1
RC2
RC3
FC1
FC2
FC3
FC4
KI1
VSSD
10p
10p
4MHz
70
65
BZ
VSSD
10
VSSD
VDDD
DSR
SEG28
SEG27
SEG26
SEG25
SEG24
SEG23
SEG22
SEG21
SEG20
SEG19
SEG18
SEG17
NJU9214
15
20
60
55
RS232C Driver
KI2
KI3
KI4
KI5
25
30
35
40
45
50
: Lock type switch
: Push type switch
APF
BATT
REL
HOLD
MAX
MIN
MEM
VSSD
F
C
AC
DC
µ m V A
AUTO
n F r p m
M k Ω Hz
RS232C
0
10
20
30
40
1 Low-leak capacitors like as the polypropylene film type are required for accurate measurement.
2 Within 0.01% tolerance resisters or the adjustment by the trimmer potentiometer are recommended.
NJU9214
( 2 ) Circuit using lock type switch ( Current Manual-4 range mode, RMS = " L " )
Reference Voltage element:over 2.5V
Temperature coefficient:below 20ppm/ C
10A COM
When Ω/
/
/ CAP,
DCV, ACV,
4mA
99
FUSE
SW1 is ON.
Ω
, CAP,
,
,
40mA
400mA
4000mA
9
When AcmA/DcmA,SW2 is ON.
DCmA, ACmA,
FRQ, rpm
BATTERY
0.9
VDDA
+5V
0.1
A D P
SW1
10K
0.01
AC measurement:AC coupling side
SW7
0.022uF
DC400mV:VI side
Others:VR2 side
SW5
0.1uF
VSSA
-5V
SW3
VDDD
+5V
Rectification
circuit
block
ACOUT
CIF1
CIF2
BLD
VSSA
SLEEP
VSSD
VDSP
XT1
XT2
BZ
TXD
DTR
100
95
90
85
80
1
5
75
VDDA
VDDD
VDDA
RMSIN
VDDD
RD1
RD2
RD3
RD4
TXS
TRX
KMS
RMS
RC0
RC1
RC2
RC3
FC1
FC2
FC3
FC4
KI1
VSSD
10p
10p
4MHz
70
65
BZ
VSSD
10
VSSD
VDDD
DSR
NJU9214
SEG28
SEG27
SEG26
SEG25
SEG24
SEG23
SEG22
SEG21
SEG20
SEG19
SEG18
SEG17
15
20
60
55
RS232C Driver
KI2
KI3
KI4
KI5
25
30
35
40
45
50
: Lock type switch
: Push type switch
APF
BATT
REL
HOLD
MAX
MIN
MEM
VSSD
F
C
AC
DC
µ m V A
n F r p m
M k Ω H z
RS232C
AUTO
0
10
20
30
40
1 Low-leak capacitors like as the polypropylene film type are required for accurate measurement.
2 Within 0.01% tolerance resistors or the adjustment by the trimmer potentiometer are recommended.
NJU9214
( 3 ) Circuit using push type switch ( Current Auto • Manual-2range mode, KMS = " L " )
Reference Voltage element:over 2.5V
Temperature coefficient:below 20ppm/ C
10A
COM
When Ω/
/
/ cap,
DCV, ACV,
FUSE
SW1 is ON.
,
, Ω, CAP,
When ACmA/DCmA,SW2 is ON.
ADP
DCmA, ACmA,
FRQ, rpm
BATTERY
VDDA
+5V
SW2
10K
AC measurement:AC coupling side
9
0.99 0.01
SW1
SW7
0.022uF
DC400mV:VI side
Others:VR2 side
SW5
0.1uF
VSSA
-5V
SW3
VDDD
+5V
Rectification
circuit
block
CIF1
CIF2
ACOUT
1
100
95
90
85
80
75
VDDA
VDDA
VSSD
BLD
RMSIN
VSSA
SLEEP
VSSD
VDSP
XT1
XT2
BZ
TXD
DTR
VDDD
VDDD
RD1
RD2
RD3
RD4
TXS
TRX
KMS
RMS
RC0
RC1
RC2
RC3
FC1
FC2
FC3
FC4
KI1
5
10p
10p
4MHz
70
65
BZ
VSS
10
VSSD
DSR
N J U 9 2 1 4
SEG28
SEG27
SEG26
SEG25
SEG24
SEG23
SEG22
SEG21
SEG20
SEG19
SEG18
SEG17
15
20
60
55
RS232C Driver
KI2
KI3
KI4
KI5
25
30
35
40
45
50
: Lock type switch
: Push type switch
APF
BATT
REL
HOLD
MAX
MIN MEM
VSSD
F
C
AC
DC
µ m V A
n F r p m
M k Ω H z
RS232C
AUTO
0
10
20
30
40
1 Low-leak capacitors like as the polypropylene film type are required for accurate measurement.
2 Within 0.01% tolerance resistors or the adjustment by the trimmer potentiometer are recommended.
NJU9214
( 4 ) Application circuit of AC voltage and AC current measurement
In case of AC voltage and AC current measurement, AC-DC conversion is required in the external circuit. In use
of the mean square circuit, the measurement circuit realizes low cost system. And also in use of RMS/DC
converter, it realizes a root-mean-square measurement. The circuit example using AD736 ( Analog Devices,Inc. )
is shown below for a root-mean-square measurement.
( The circuit is for only reference, so please refer to the data book of Analog Devices, Inc. for details. )
10M
NJU9214
VR2(PIN99)
0.022uF
ACOUT(PIN1)
RMSIN(PIN3)
VDDA
SW4_1
1N4148
47K
AC4V to 4000V range
SW4_2
10uF
1N4148
AD736
Full-wave
rectifier
1
2
3
4
8
7
AGND
VDDA
VSSA
AC400mV
6
5
RMS
AC400mV
Converter
block
+
33uF
VSSA
10uF
Rectifier circuit block
( 5 ) Notes of application circuits
1.The power source for NJU9214 is required stable, and enough current drivability.
2.Capacitors marked with 1 require low-leak type like as the polypropylene film.
3.Resistance ratio precision of input attenuator block affects measurement precision.
Resistances marked with 2 requires within 0.01% tolerance resistors or adjustment by the trimmer potentiom-
eter.
4.Designing of circuit pattern requires low wiring resistance between AGND terminal and SGND terminal.
5.Constants of resistances for voltage dividing and decoupling capacitor are not guaranteed value as to character-
istic. Re adjustment is sometime required depending on elements and peripheral circuit.
6.RMS/DC converter requires full-scale and zero adjustment.
NJU9214
MEMO
[CAUTION]
The specifications on this databook are only
given for information , without any guarantee
as regards either mistakes or omissions. The
application circuits in this databook are
described only to show representative usages
of the product and not intended for the
guarantee or permission of any right including
the industrial rights.
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