NJM2748/2748A
-1-
Ver.2007-05-24
Low Offset, Low Drift single JFET Input
Operational Amplifier
GENERAL DESCRIPTION PACKAGE OUTLINE
The NJM2748/2748A is a Precision dual JFET input operational
amplifier which includes low input offset voltage: 0.7mV (typ) / 2.0mV
(max) and 6µV/°C typical offset drift.
The NJM2748A is guaranteed 20µV/°C maximum offset drift to
perform a 100% tested.
The NJM2748/2748A have the following features: low bias current of
50pA (typ), high slew rate of 13V/µs (typ).
These features are suitable for signal processing amplifiers of
instrumentation, measurement and industrial applications such as
sensor amplifier, current sensing and sample-and-hold circuit.
FEATURES
Input Offset Voltage Drift NJM2748: V
IO
/T= 6µV/°C typ.
NJM2748A: V
IO
/T=20µV/°C max.
Input Offset Voltage 2.0mV max. @Ta=25°C ~ 85°C
3.0mV max. @Ta= -40°C
Input Bias Current I
B
= 50pA typ. 200pA max. @Ta=25°C
Slew Rate SR=13V/µs typ. @Ta=25°C
Operating Voltage Vopr= ±6.0V ~ ±16V
Voltage Gain Av=100dB typ.
Bipolar Technology
Package Outline NJM2748D, NJM2748AD :DIP8
NJM2748M, NJM2748AM :DMP8
PIN CONFIGURATION
NJM2748D/2748AD
NJM2748M/2748AM
8
7
6
5
1
2
3
4
BALANC
E
V
INPUT
A
+INPUT
A
NC
BALANCE
V
+
OUTPUT
(Top View)
NJM2748/2748A
NJM2748/2748A
- 2 -
Ver.2007-05-24
ABSOLUTE MAXIMUM RATING (Ta=25°C unless otherwise specified)
PARAMETER SYMBOL RATING UNIT
Supply Voltage V
+
/V
-
±
18 V
Common Mode Input Voltage V
ICM
±
15 (Note1) V
Differential Input Voltage V
ID
±
30 V
500 [ DIP8 ], 300 [ DMP8 ] mW
430 [ DMP8 ] (Note2) mW
Power Dissipation P
D
580 [ DMP8 ] (Note3) mW
Operating Temperature Range Topr -40 ~ +85
°C
Storage Temperature Range Tstg -50 ~ +125
°C
(Note1) For supply voltage less than ±18V, the maximum input voltage is equal to the supply voltage.
(Note2) Mounted on the EIA/JEDEC standard board (76.2×114.3×1.6mm, two layer, FR-4).
(Note3) Mounted on the EIA/JEDEC standard board (76.2×114.3×1.6mm, four layer, FR-4).
RECOMMENDED OPERATING VOLTAGE (Ta=25°C)
PARAMETER SYMBOL RATING MIN. TYP. MAX. UNIT
Supply Voltage V
+
/V
-
±6 - ±16 V
ELECTRONIC CHARACTERISTICS
DC CHARACTERISTICS (V
+
/V
-
=±15V, Ta=-40 to +85°C (Note4) unless otherwise specified)
PARAMETER SYMBOL CONDITION MIN. TYP. MAX. UNIT
NJM2748A 6 20
Input Offset Voltage Drift V
IO
/T
NJM2748
(Note5, 6) 6
µV/°C
Input Offset Voltage1 V
IO1
R
S
=50, Ta=+85°C (Note6, 7) 0.6 2.0 mV
Input Offset Voltage2 V
IO2
R
S
=50, Ta=+25°C (Note6, 7) 0.7 2.0 mV
Input Offset Voltage3 V
IO3
R
S
=50, Ta=40°C (Note6, 7) 0.9 3.0 mV
Common Mode Rejection Ratio CMR V
ICM
=±10V (Note8) 76 92 dB
Supply Voltage Rejection Ratio SVR V
+
/V
=±6V ~ ±16V (Note7, 9) 80 100 dB
Input Common Mode Voltage Range 1 V
ICM1
CMR76dB (Note10) +10 +14.5 V
Input Common Mode Voltage Range 2 V
ICM2
CMR76dB (Note10) 11 10 V
Input Bias Current 1 I
B1
Ta=+25°C (Note7) 50 200 pA
Input Bias Current 2 I
B2
Ta=+85°C (Note7) 4 nA
Input Offset Current 1 I
IO1
Ta=+25°C (Note7) 25 100 pA
Input Offset Current 2 I
IO2
Ta=+85°C (Note7) 2 nA
Voltage Gain 1 Av1 R
L
=2k, Vo=±10V, Ta=+25°C 88 100 dB
Voltage Gain 2 Av2 R
L
=2k, Vo=±10V 82 100 dB
Maximum Output Voltage 1 V
OM1
R
L
=10k ±12 ±13.5 V
Maximum Output Voltage 2 V
OM2
R
L
=2k ±10 ±11.5 V
Supply Current Icc Voltage Follower, R
L
= (Note7) 2.0 3.4 mA
NJM2748/2748A
-
3
-
Ver.2007-05-24
(Note4) These devices are measured under three temperature conditions of Ta=40°C, +25°C, +85°C.
(Note5) Temperature coefficient is calculated by specified change in offset voltage. (Changes Ta=+25°C to 40°C and Ta=+25°C to +85°C)
NJM2748A is guaranteed maximum specification because these are 100% tested to operating temperature range.
NJM2748 is guaranteed only typical specification.
(Note6) Written by the absolute rate.
(Note7) Measured at V
ICM
=0V
(Note8) CMR is calculated by specified change in offset voltage. (V
ICM
=0V to +10V and V
ICM
=0V to 10V)
(Note9) SVR is calculated by specified change in offset voltage. (V
+
/V
=±6V to ±16V)
(Note10) V
ICM
is input common mode voltage when tested meets specified change in offset voltage is CMR76dB.
(A point of reference is offset voltage of V
ICM
=0V)
AC CHARACTERISTICS (V
+
/V
=±15V, Ta=+25°C unless otherwise specified)
PARAMETER SYMBOL CONDITION MIN. TYP. MAX. UNIT
Gain Bandwidth Product GB f=10kHz 2.2 MHz
Unity Gain Frequency f
T
AV=+100, R
S
=100, RL=, CL=10pF 2 MHz
Phase Margin
M
AV=+100, R
S
=100, RL=, CL=10pF 55 deg
Input Noise Voltage1 V
NI1
f=1kHz, A
V
=+100, RS=100, RL= 20 nV/Hz
Input Noise Voltage2 V
NI2
RIAA, R
S
=2.2k, 30kHz, LPF 2.5 µVrms
Total Harmonic Distortion THD f=1kHz, A
V
=+10, R
S
=1k, R
L
=, V
O
=5Vrms 0.005 %
TRANSIENT CHARACTERISTICS (V
+
/V
-
=±15V, Ta=+25°C unless otherwise specified)
PARAMETER SYMBOL CONDITION MIN. TYP. MAX. UNIT
Positive Slew Rate +SR A
V
=+1, V
IN
=2Vpp, R
L
=10k, C
L
=10pF 14 V/µs
Negative Slew Rate -SR A
V
=+1, V
IN
=2Vpp, R
L
=10k, C
L
=10pF 12 V/µs
NJM2748/2748A
- 4 -
Ver.2007-05-24
IMPORTANT CONSIDERATIONS FOR USE OF NJM2748/2748A
Supply Current
When Ta25°C, Power Dissipation P
D
is limited by junction temperature (T
J
=125°C)
So maximum supply current is influenced by package, mounting board (board size, area of cupper foil), Mounting condition and
etc.
Following DMP8 Power Dissipation characteristic is a characteristic when mounted the following conditions supply.
Two layer board: EIA/JEDEC 76.2×114.3×1.6mm, FR-4
Four layer board: EIA/JEDEC 76.2×114.3×1.6mm, FR-4
Please refer to "Method of measuring the package thermal characteristic" published in our company web site for detailed
information on the thermal characteristic.
THE OSCILLATION WITH A CAPACITIVE LOAD
NJM2748/2748A tends to oscillate easily when it uses voltage-follower, and driving capacitive load.
The figure below is a “Voltage Gain - Frequency characteristic” in the Voltage-Follower. (It is not the one to guarantee the
characteristic of the product.)
Especially, it becomes easy to oscillate in the condition that the input voltage (output voltage) is near the minus supply voltage
side and the condition with large output sink current. We will recommend use by some circuit gains.
Maximum Power Dissipation
Ambient Temperature
(DMP8)
0
100
200
300
400
500
600
0 20406080100
Ambient Temperature [ºC]
Power Dissipation P
D
[mW]
EIA/JEDEC
4-Layer
EIA/JEDEC
2-Layer
Package
Only
Maximum Power Dissipation
Ambient Temperature
(DIP8)
0
100
200
300
400
500
600
0 20406080100
Ambient Temperature [ºC]
Power Dissipation P
D
[mW]
Voltage Gain
Frequency
(V
+
++
+
/V
15V, Voltage Follower,
C
L
=100pF, I
SINK
=1mA, Ta=25ºC)
-5
0
5
10
15
10k 100k 1000k 10000k
Frequency [HZ]
Voltage Gain [dB]
V
O
=-10V
V
O
=0V
V
O
=+10V
1M 10M
Voltage Gain
Frequency
(V
+
++
+
/V
15V, Voltage Follower,
C
L
=100pF, V
O
=
10V, Ta=25ºC)
-5
0
5
10
15
10k 100k 1000k 10000k
Frequency [HZ]
Voltage Gain [dB]
I
SINK
=5mA
I
SINK
=2mA
I
SINK
=1mA
1M 10M
NJM2748/2748A
-
5
-
Ver.2007-05-24
IMPORTANT CONSIDERATIONS FOR USE OF NJM2748/2748A
INPUT COMMON MODE VOLTAGE RANGE
In this product, the input offset voltage drift is measured based on the input offset voltage at V
ICM
=0V, and the input voltage
range that satisfies the common mode rejection ratio 76dB is defined as the input common mode voltage range.
As an electric characteristic, V
ICM
=10V~+10V at Supply Voltage V
+
/V
=±15V is guaranteed.
It becomes below formula about the input common mode voltage range when the supply voltage changes.
+V
ICM
: (V
+
supply) 5 [V] · · · reference
V
ICM
: (V
supply) + 5 [V] · · · reference
This figure below is “Input common mode voltage range – Supply voltage characteristics”. (It is not the one to guarantee the
characteristic of the product.)
+ V
ICM
is limited by the absolute maximum rating (V
+
supply) within the input common mode voltage range.
Moreover, V
ICM
tends to rise by lowering of the supply voltage.
Common Mode Input Voltage Range (+V
ICM
)
Supply Voltage
(Ta=25ºC, CMR=76dB)
-2.0
-1.0
0.0
1.0
5 101520
Supply Voltage V
+
++
+
/V
[V]
(V
+
Supply)
(+V
ICM
) [V]
Common Mode Input Voltage Range (
V
ICM
)
Supply Voltage
(Ta=25ºC, CMR=76dB)
2.0
3.0
4.0
5.0
5 101520
Supply Voltage V
+
++
+
/V
[V]
(
V
ICM
)
(V
Supply) [V]
NJM2748/2748A
-
6
-
Ver.2007-05-24
OFFSET VOLTAGE TRIM CIRCUIT
The NJM2748 provides offset voltage trim connections on pin 1 and 5.
The offset voltage can be adjusted by connecting Potentiometer as shown in figure.
This function adjusts an initial offset voltage, and it doesn't become an improvement of the temperature drift.
Please make pin1 and pin5 open when you don’t use this function.
OTHERS
For the NJM2748/2748A are high-precision products, a surface leak by dirt and/or condensation on package can have a
detrimental effect on precise characteristics of these products.
You should pay close attention to environment of storage and usage.
V
+
V
-
2
3
1
5
4
7
20k
R=7.5k R=7.5k
Trim Resistor R=5.0k
R
1
R
2
-15V
1pin 5pin
Input Offset Voltage vs. Trim Resistor R1
V
+
/V
-
15V, Rtrim=5k, R=7.5k, Ta=25°C
-8
-6
-4
-2
0
2
4
6
8
01k2k3k4k5k
Trim Resistor R1 []
Input Offset Voltage [mV]
NJM2748/2748A
-7-
Ver.2007-05-24
TYPICAL CHARACTERISTICS
Input Offset Voltage Drift
Common Mode Input Voltage
(V
+
++
+
/V
15V)
-1000
-500
0
500
1000
-15 -10 -5 0 5 10 15
Common Mode Input Voltage [V]
Input Offset Voltage Drift [µV]
Ta=85ºC
Ta=25ºC
Ta=-40ºC
Input Offset Voltage Drift
Supply Voltage
(V
+
++
+
/V
15V of Reference)
-1000
-500
0
500
1000
5 101520
Supply Voltage V
+
++
+
/V
[V]
Input Offset Voltage Drift [µV]
Ta=85ºC
Ta=-40ºC
Ta=25ºC
Input Offset Voltage Temperature Coefficient
Distribution
(V
+
/V
-
15V, Ta=
40ºC
→+
→+→+
→+
25ºC)
0
20
40
60
80
100
120
140
-20
-16
-12
-8
-4
0
4
8
12
16
20
Distribution [µV/ºC]
Number of Units
Input Offset Voltage Temperature Coefficient
Distribution
(V
+
/V
-
15V, Ta=
+
++
+
25ºC
→+
→+→+
→+
85ºC)
0
20
40
60
80
100
120
140
-20
-16
-12
-8
-4
0
4
8
12
16
20
Distribution [µV/ºC]
Number Of Units
Input Offset Voltage
Ambient Temperature
(V
+
/V
-
15V)
-2000
-1000
0
1000
2000
-50 -25 0 25 50 75 100
Ambient Temperature [ºC]
Input Offset Voltage [µV]
Input Offset Voltage Drift
Common Mode Input Voltage
(V
+
/V
-
15V, V
ICM
=0V of Reference, Ta=25ºC)
-1000
-500
0
500
1000
-15-10-5 0 5 1015
Common Mode Input Voltage V
ICM
[V]
Input Offset Voltage Drift [µV]
NJM2748/2748A
-
8
-
Ver.2007-05-24
TYPICAL CHARACTERISTICS
Common Mode Rejection Ratio
Ambient Temperature
(V
+
++
+
/V
15V, V
ICM
=0V
10V)
70
80
90
100
110
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Common Mode Rejection Ratio
CMR [dB]
Supply Voltage Rejection Ratio
Ambient Temperature
(V
+
++
+
/V
=±6V
±16V)
70
80
90
100
110
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Supply Voltage Rejection Ratio
SVR [dB]
Common Mode Rejection Ratio
Frequency
(Input Ripple Voltage=1V
PP
, V
+
++
+
/V
15V, A
V
=60dB)
0
20
40
60
80
100
120
0k 0k 1k 10k 100k 1000k
Frequency [kHz]
Common Mode Rejection Ratio
CMR [dB]
Ta=-40°C
Ta=25°C
Ta=85°C
10 100 1M
Common Mode Rejection Ratio
Frequency
(Input Ripple Voltage=1V
PP
, V
+
++
+
/V
=±6V, A
V
=60dB)
0
20
40
60
80
100
120
0k 0k 1k 10k 100k 1000k
Frequency [Hz]
Common Mode Rejection Ratio
CMR [dB]
Ta=-40°C
Ta=25°C
Ta=85°C
10 100 1M
Supply Voltage Rejection Ratio (+Supply)
Frequency
(Ripple Voltage=1V
PP
, V
+
++
+
/V
15V, A
V
=40dB)
0
20
40
60
80
100
120
0k 0k 1k 10k 100k 1000k
Frequency [Hz]
Supply Voltage Rejection Ratio
SVR [dB]
Ta=85°C
Ta=25°C
Ta=-40°C
10 100 1M
Supply Voltage Rejection Ratio (
Supply)
Frequency
(Ripple Voltage=1V
PP
, V
+
++
+
/V
15V, A
V
=40dB )
0
20
40
60
80
100
120
0k 0k 1k 10k 100k 1000k
Frequency [Hz]
Supply Voltage Rejection Ratio
SVR [dB]
Ta=85°C
Ta=25°C
Ta=-40°C
10 100 1M
NJM2748/2748A
-
9
-
Ver.2007-05-24
TYPICAL CHARACTERISTICS
Input Bias Current
Common Mode Input Voltage
(V
+
++
+
/V
15V, Ta=25ºC)
0
50
100
-15 -10 -5 0 5 10 15
Common Mode Input Voltage V
ICM
[V]
Input Bias Current I
B
[pA]
Input Bias Current
Supply Voltage
(Ta=25ºC, V
ICM
=0V)
0
50
100
5 101520
Supply Voltage V
+
++
+
/V
[V]
Input Bias Current I
B
[pA]
Input Bias Current
Ambient Temperature
(V
+
++
+
/V
15V, V
ICM
=0V)
1
10
100
1000
10000
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Input Bias Current I
B
[pA]
Input Offset Current
Ambient Temperature
(V
+
++
+
/V
15V, V
ICM
=0V)
-600
-400
-200
0
200
400
600
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Input Offset Current I
IO
[pA]
Supply Current
Ambient Temperature
(V
+
/V
-
15V, Voltage Follower, R
L
=open)
1.0
1.5
2.0
2.5
3.0
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Supply Current I
CC
[mA]
Supply Current
Supply Voltage
(Voltage Follower, R
L
=open)
1.0
1.5
2.0
2.5
3.0
5101520
Supply Voltage V
+
/V
-
[V
+
/V
-
]
Supply Current I
CC
[mA]
Ta=-40ºC
Ta=85ºC
Ta=25ºC
NJM2748/2748A
- 1
0
-
Ver.2007-05-24
TYPICAL CHARACTERISTICS
Maximum Output Voltage (+V
OM
)
Output Source Current
(V
+
++
+
/V
15V)
11
12
13
14
15
0 10203040
Output Source Current I
SOURCE
[mA]
Maximum Output Voltage
+V
OM
[V]
Ta=85ºC
Ta=-40ºC
Ta=25ºC
Output Saturation Voltage (+V
OS
)
Supply Voltage
(Ta=25ºC)
0.0
0.5
1.0
1.5
5101520
Supply Voltage V
+
++
+
/V
[V]
Output Saturation Voltage
+V
OS
[V]
I
SOURCE
=10mA
I
SOURCE
=2mA
I
SOURCE
=5mA
+V
OS
=(V
+
) - (+V
OM
)
Maximum Output Voltage (
V
OM
)
Output Sink Current
(V
+
++
+
/V
15V)
-14
-13
-12
-11
-10
0 10203040
Output Sink Current I
SINK
[mA]
Maximum Output Current
V
OM
[V]
Ta=85ºC
Ta=-40ºC
Ta=25ºC
Output Saturation Voltage (
V
OS
)
Supply Voltage
(Ta=25ºC)
1.0
1.5
2.0
2.5
5101520
Supply Voltage V
+
++
+
/V
[V]
Output Saturation Voltage
V
OS
[V]
-V
OS
=(-V
OM
) - (V
-
)
I
SINK
=10mA
I
SINK
=2mA
I
SINK
=5mA
Voltage Gain
Ambient Temperature
(V
+
++
+
/V
15V, V
O
10V, R
L
=2k)
90
100
110
120
130
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Voltage Gain A
V
[dB]
Unity
Gain Frequency
Ambient Temperature
(V
+
++
+
/V
15V, 40dBAMP, C
L
=10pF)
1
1.5
2
2.5
3
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Unity
Gain Frequency f
T
[MHz]
NJM2748/2748A
-11-
Ver.2007-05-24
TYPICAL CHARACTERISTICS
Gain/Phase
Frequency
(V
+
++
+
/V
15V, 40dBAMP, C
L
=100pF, Ta=25ºC)
-10
0
10
20
30
40
50
1k 10k 100k 1000k 10000k
Frequency [Hz]
Voltage Gain A
V
[dB]
-180
-135
-90
-45
0
45
90
Phase φ [deg]
Gain
Phase
1M 10M
Gain/Phase
Frequency
(V
+
++
+
/V
=±6V, 40dBAMP, C
L
=100pF, Ta=25ºC)
-10
0
10
20
30
40
50
1 10 100 1000 10000
Frequency [kHz]
Voltage Gain A
V
[dB]
-180
-135
-90
-45
0
45
90
Phase φ [deg]
Gain
Phase
1M 10M
Voltage Gain
Frequency
(V
+
++
+
/V
15V, Voltage Follower, R
L
=2k, Ta=25ºC)
-5
0
5
10
0M 1M 10M
Frequency [Hz]
Voltage Gain A
V
[dB]
C
L
=100pF
C
L
=47pF
C
L
=10pF
100k
Voltage Gain
Frequency
(V
+
++
+
/V
=±6V, Voltage Follower, R
L
=2k, Ta=25ºC)
-5
0
5
10
0M 1M 10M
Frequency [Hz]
Voltage Gain A
V
[dB]
C
L
=100pF
C
L
=47pF
C
L
=10pF
100k
Voltage Gain
Frequency
(V
+
++
+
/V
15V, Voltage Follower, R
L
=2k, C
L
=100pF)
-5
0
5
10
0M 1M 10M
Frequency [Hz]
Voltage Gain A
V
[dB]
Ta=85ºC
Ta=-40ºC
Ta=25ºC
100k
Voltage Gain
Frequency
(V
+
++
+
/V
=±6V, Voltage Follower, R
L
=2k, C
L
=100pF)
-5
0
5
10
0M 1M 10M
Frequency [Hz]
Voltage Gain A
V
[dB]
Ta=85ºC
Ta=-40ºC
Ta=25ºC
100k
NJM2748/2748A
- 12 -
Ver.2007-05-24
TYPICAL CHARACTERISTICS
Slew Rate
Ambient Temperature
(V
+
++
+
/V
15V, Voltage Follower, V
O
1V, R
L
=2k)
5
10
15
20
-50 -25 0 25 50 75 100 125
Ambient Temperature [ºC]
Slew Rate SR [V/µs]
+SR
-SR
Slew Rate
Supply Voltage
(Voltage Follower, V
O
1V, R
L
=2k, Ta=25ºC)
5
10
15
20
5101520
Supply Voltage V
+
++
+
/V
[V]
Slew Rate SR [V/µs]
+SR
-SR
THD+N
Output Voltage
(R
F
=9k, V
+
++
+
/V
15V, A
V
=+10, R
L
=open, Ta=25ºC)
0.001
0.01
0.1
1
0.01 0.1 1 10
Output Voltage V
O
[Vrms]
THD+N [%]
20kHz
20Hz
1kHz
THD+N
Frequency
(R
F
=9k, V
+
++
+
/V
15V, A
V
=+10, R
L
=open, Ta=25ºC)
0.001
0.01
0.1
1
0k 0k 1k 10k 100k
Frequency [Hz]
THD+N [%]
V
O
=7.07Vrms
V
O
=5Vrms
10 100
THD+N
Output Voltage
(R
F
=1.8k, V
+
++
+
/V
15V, A
V
=+10, R
L
=open, Ta=25ºC)
0.001
0.01
0.1
1
0.01 0.1 1 10
Output Voltage V
O
[Vrms]
THD+N [%]
20kHz
20Hz
1kHz
THD+N
Frequency
(R
F
=1.8k, V
+
++
+
/V
15V, A
V
=+10, R
L
=open, Ta=25ºC)
0.001
0.01
0.1
1
0k 0k 1k 10k 100k
Frequency [Hz]
THD+N [%]
V
O
=7.07Vrms
V
O
=5Vrms
10 100
NJM2748/2748A
-1
3
-
Ver.2007-05-24
TYPICAL CHARACTERISTICS
Equivalent Input Noise Voltage
Frequency
(V
+
++
+
/V
15V, 40dBAMP, R
S
=100, Ta=25ºC)
0
10
20
30
40
50
60
1 10 100 1000 10000
Frequency [Hz]
Equivalent Input Noise Voltage
V
NI
[nV/
Hz]
1k 10k
[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.