NJU9252P
2-DIGIT SINGLE CHIP A/D CONVERTER
QGENERAL DESCRIPTION QPACKAGE OUTLINE
The NJU9252P is a low operating current, high
performance 2-digit single chip A/D converter containing a
sample/hold circuit, an oscillator, a 7-segment decoder, LED
display driver and a control circuit. The LED display
changes by the high-speed sampling rate of 4 times/s (typ).
The NJU9252P realizes to apply with few external
components, therefore it is most suited for digital meters,
digital thermometers and the others.
QFEATURES QPAD LOCATION
O8bit Resolution, Successive Approximation Method
OLow Input Current ( 1µA typ )
ODynamic LED direct drive
OSampling-rate ( 4 times/s typ )
OSample/Hold Circuit On-Die
OCR Oscillation Circuit On-Die
OPower-on Initialization
OOffset Adjustment Terminal
OLow operating current
OApplicable with Few External Components
OC-MOS technology
OPackage DMP20
NJU9252PM
SEG D
SEG C
SEG B
SEG A
SEG F
SEG G
SEG E
NC
COM1
V
SS
VDD
VREF
INH
INL
INR
OFFSET 2
OFFSET 1
NC
TEST
COM2
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
DMP20
NJU9252P
QBLOCK DIAGRAM
QTERMINAL DESCRIPTION
SYMBOL FUNCTION
SEG D LED Segment Driver D output ( Pch open-drain )
SEG C LED Segment Driver C output ( Pch open-drain )
SEG B LED Segment Driver B output ( Pch open-drain )
SEG A LED Segment Driver A output ( Pch open-drain )
SEG F LED Segment Driver F output ( Pch open-drain )
SEG G LED Segment Driver G output ( Pch open-drain )
SEG E LED Segment Driver E output ( Pch open-drain )
COM1 LED Common Driver output 1 ( Nch open-drain )
VSS GND
COM2 LED Common Driver output 2 ( Nch open-drain )
TEST Test Termina l
OFFSET 1 Offset Adjustment Terminal 1
OFFSET 2 Offset Adjustment Terminal 2
INR Input Gain setup Resistor Connecting Terminal
INL Analog Differential Input ( Lo )
INH Analog Differential Input ( Hi )
VREF Reference Voltage
VDD Supply Voltage
NC Non Connection
SEG A
(Pch OPEN
DRAIN)
SEGMENT
DECODER LATCH
MULTI
PLEXER
SEGMENT
DRIVER
COMMON
DRIVER
OSC
DAC
CLOCK
SHIFT
REGISTER
SAMPLE
& HOLD COMP
DIF
A
MP
BIN
BCD
INH
INL
INR
OFFSET 1
TEST
VDD
VSS
COM 1 2
(Nch OPEN
DRAIN)
VREF
DIV LAT
POWER
ON
RESET
OFFSET 2
B C E F GD
NJU9252P
QABSOLUTE MAXIMUM RATINGS
(Ta=25°C)
PARAMETER SYMBOL RATING UNIT
Supply Voltage VDD -0.3 to +7.0 V
Analog Input Voltage VIN GND to VREF V
Reference Input Voltage VREF GND to VDD V
Power Dissipation PD 500 mW
Operating Temperature Range Topr -20 to +75 °C
Storage Temperature Range Tstg -40 to +125 °C
Note1) The input current is limited to ±100µA when the input voltage is more than supply voltage.
QELECTRICAL CHARACTERISTICS
(VDD=5V, Ta=25°C)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNIT
Operating Voltage VDD 4.5 5.0 5.5 V
Ratiometric Reading N99 VIN=2.475V, VREF=3.2V 98 98/99 99 Counts
Linearity DL Full Scale=2.475V Note2) ±0.5 ±2 LSB
Offset EOFF V
REF=3.2V ±1 ±2 LSB
Noise ( P-P Value ) VNI VIN=0.0V Note3)
Full Scale=2.475V 30 µV
Leakage Current IL V
IN=0.0V 1 5 µA
Zero Reading Drift ZD VIN=0.0V, VREF=3.2V,
-20<Ta<+75°C 0.2 1 µV/°C
Scale Factor
Temperature Coefficient Ftemp VIN=2.475V, VREF=3.2V,
-20<Ta<+75°C (Ext.ref, 0ppm/°C) 1 5
ppm
/°C
Sampling-rate Ts 3 4 5 times/s
Operating Current IDD V
IN=0.0V 0.8 1.8 mA
IS1 Segment Voltage=3V
SEG A to SEG G Terminals 10 14 mA
Segment Sink Current
IS2 Segment Voltage=3V
COM1, COM2 Terminals 70 98 mA
Note2) Linearity indicates an error of the input-output linearity characteristics getting with the two read data of
zero and full scale input values.
Note3) The peak value of noise must be kept within this value during 95% period in the measurement time.
NJU9252P
QTIMING CHART
Note4) SEG A to SEG G are an example to display “ 25 “.
The duty of COM1 and COM2 are 50% respectively.
COM1 and COM2 are Nch-FET open-drain type, SEG A to SEG G are Pch-FET open-drain type.
: The state of Output Terminal is high impedance.
TCONV
Internal Clock
COM1
COM2
SEG
A
SEG B
SEG C
SEG D
SEG E
SEG F
SEG G
NJU9252P
QDISPLAY PATTERN
QAPPLICATION CIRCUIT ( Ex. NJU9252PM)
OThermometer
0 1 2 3 4 5 6 7 8 9
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
+5V
10uF
10kΩ
10kΩ
1uF
Full-Scale
Adj.
Zero Adj.
LED
(CATHODE COMMON)
Thermistor
NJU9252PM
Offset Adj.
[CAUTION]
The specifications on this data book are only
given for information , without any guarantee
as regards either mistakes or omissions.
The application circuits in this data book 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.
NC
NC
