TC913A/TC913B
Dual Auto-Zeroed Operational Amplifiers
Features
• First Monolithic Dual Auto-Zeroed
Operational Amplifier
• Chopper Amplifier Performance Without External
Capacitors
- V
OS
: 15µV Max
- V
OS
: Drift; 0.15µV/°C Max
- Saves Cost of External Capacitors
• SOIC Packages Available
• High DC Gain; 120dB
• Low Supply Current; 650µA
• Low Input Voltage Noise
- 0.65µV
P-P
(0.1Hz to 10Hz)
• Wide Common Mode Voltage Range
- V
SS
to V
DD
- 2V
• High Common Mode Rejection; 116dB
• Dual or Single Supply Operation:
- ±3.3V to ±8.3V
- +6.5V to +16V
• Excellent AC Operating Characteristics
- Slew Rate; 2.5V/µsec
- Unity-Gain Bandwidth; 1.5MHz
• Pin Compatible with LM358, OP-14, MC1458,
ICL7621, TL082, TLC322
Package Type
PDIP
TC913ACPA
TC913BCPA
OUT A 1
-IN A 2
+IN A 3
V
SS
A
+ -
A
+ -
8 V
B
-
+
DD
7 OUT B
6 -IN B
5 +IN B
4
SOIC
TC913ACOA
TC913BCOA
OUT A 1
-IN A 2
+IN A 3
V
SS
8 V
DD
B
-
+
7 OUT B
6 -IN B
5 +IN B
4
General Description
The TC913 is the world's first complete monolithic, dual
auto-zeroed operational amplifier. The TC913 sets a
new standard for low power, precision dual-operational
amplifiers. Chopper-stabilized or auto-zeroed amplifi-
ers offer low offset voltage errors by periodically sam-
pling offset error, and storing correction voltages on
capacitors. Previous single amplifier designs required
two user-supplied, external 0.1µF error storage correc-
tion capacitors — much too large for on-chip integra-
tion. The unique TC913 architecture requires smaller
capacitors, making on-chip integration possible.
Microvolt offset levels are achieved and
external
capacitors are not required.
The TC913 system benefits are apparent when con-
trasted with a TC7650 chopper amplifier circuit imple-
mentation. A single TC913 replaces two TC7650's and
four capacitors. Five components and assembly steps
are eliminated.
Applications
•
•
•
•
•
Instrumentation
Medical Instrumentation
Embedded Control
Temperature Sensor Amplifier
Strain Gage Amplifier
Device Selection Table
Part Number
TC913ACOA
TC913ACPA
TC913BCOA
TC913BCPA
Package
8-Pin SOIC
8-Pin PDIP
8-Pin SOIC
8-Pin PDIP
Temp.
Range
0°C to
+70°C
0°C to
+70°C
0°C to
+70°C
0°C to
+70°C
Offset
Voltage
15µV
15µV
30µV
30µV
The TC913 pinout matches many popular dual-opera-
tional amplifiers: OP-04, TLC322, LM358, and ICL7621
are typical examples. In many applications, operating
from dual 5V power supplies or single supplies, the
TC913 offers superior electrical performance, and can
be a functional drop-in replacement; printed circuit
board rework is not necessary. The TC913's low offset
voltage error eliminates offset voltage trim
potentiometers often needed with bipolar and low
accuracy CMOS operational amplifiers.
The TC913 takes full advantage of Microchip's
proprietary CMOS technology. Unity gain bandwidth is
1.5MHz and slew rate is 2.5V/µsec.
2002 Microchip Technology Inc.
DS21482B-page 1
©
TC913A/TC913B
Functional Block Diagram
V
SS
4
V
DD
8
TC913
V
OS
Correction Amplifier
+
A
–
*
B
A
B
Internal
Oscillator
(f
OSC
200Hz)
*
-Input
-Input
+Input
+Input
A
B
A
B
2
6
5
3
-
+
Main Amplifier
1 of 2 Amplifier Shown
Low Impedance
Output Buffer
+
-
1
7
Output A
Output B
*NOTE:
Internal capacitors. No external capacitors required.
©
DS21482B-page 2
2002 Microchip Technology Inc.
TC913A/TC913B
1.0
ELECTRICAL
CHARACTERISTICS
*Stresses above those listed under "Absolute Maximum
Ratings" may cause permanent damage to the device. These
are stress ratings only and functional operation of the device
at these or any other conditions above those indicated in the
operation sections of the specifications is not implied. Expo-
sure to Absolute Maximum Rating conditions for extended
periods may affect device reliability.
Absolute Maximum Ratings*
Total Supply Voltage (V
DD
to V
SS
) .......................+18V
Input Voltage ...................... (V
DD
+0.3V) to (V
SS -
0.3V)
Current Into Any Pin............................................ 10mA
While Operating .......................................... 100µA
Package Power Dissipation (T
A
– 70°C)
Plastic DIP ................................................ 730mW
Plastic SOIC ............................................. 470mW
Operating Temperature Range
C Device .......................................... 0°C to +70°C
Storage Temperature Range .............. -65°C to +150°C
TC913A AND TC913B ELECTRICAL SPECIFICATIONS
Electrical Characteristics:
V
S
= ±5V, T
A
= +25°C, unless otherwise indicated.
TC913A
Symbol
V
OS
TCV
OS
Parameter
Input Offset
Voltage
Average Temp.
Coefficient of
Input Offset
Voltage
Average Input
Bias Current
Average Input
Offset Current
Input Voltage
Noise
Common Mode
Rejection Ratio
Common Mode
Voltage Range
Open-Loop
Voltage Gain
Output Voltage
Swing
Closed Loop
Bandwidth
Slew Rate
Power Supply
Rejection Ratio
Operating
Supply Voltage
Range
Quiescent
Supply Current
1:
TC913B
Max
15
0.15
0.15
Min
—
—
—
Typ
15
0.1
0.1
Max
30
0.25
0.25
Unit
µV
µV/°C
µV/°C
Test Conditions
T
A
= +25°C
0°C
≤
T
A
≤
+70°C
-25°C
≤
T
A
≤
+85°C
(Note 1)
T
A
= +25°C
0°C
≤
T
A
≤
+70°C
-25°C
≤
T
A
≤
+85°
T
A
= +25°C
T
A
= +85°C
0.1 to 1 Hz, R
S
≤
100Ω
0.1 to 10 Hz, R
S
≤
100Ω
V
SS
≤
V
CM
≤
V
DD
- 2.2
Min
—
—
—
Typ
5
0.05
0.05
I
B
—
—
—
—
—
—
—
110
V
SS
115
V
SS
+ 0.3
—
—
110
±3.3
6.5
—
—
—
—
5
—
0.6
11
116
—
90
3
4
20
1
—
—
—
V
DD -
2
—
V
DD
- 0.9
—
—
—
±8.3
16
0.85
—
—
—
—
—
—
—
100
V
SS
110
V
SS
+ 0.3
—
—
100
±3.3
6.5
—
—
—
—
10
—
0.6
11
110
—
120
4
6
40
1
—
—
—
V
DD -
2
—
V
DD
-0.9
—
—
—
±8.3
16
1.1
pA
nA
nA
pA
nA
µV
P-P
µV
P-P
dB
V
dB
V
MHz
I
OS
e
N
CMRR
CMVR
A
OL
V
OUT
BW
SR
PSRR
V
S
120
—
1.5
2.5
—
—
—
0.65
120
—
1.5
2.5
—
—
—
—
R
L
= 10 kΩ, V
OUT
= ±4V
R
L
= 10 kΩ
Closed Loop Gain = +1
V/µsec R
L
= 10 kΩ, C
L
= 50 pF
dB
V
V
mA
±3.3V to ±5.5V
Split Supply
Single Supply
V
S
= ±5V
I
S
Note
Characterized; not 100% tested.
2002 Microchip Technology Inc.
DS21482B-page 3
©
TC913A/TC913B
2.0
PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 2-1.
TABLE 2-1:
Pin No.
(8-Pin PDIP)
(8-Pin SOIC)
1
2
3
4
5
6
7
8
PIN FUNCTION TABLE
Symbol
OUT A
-IN A
+IN A
V
SS
+IN B
-IN B
OUT B
V
DD
Output
Inverting Input
Non-inverting Input
Negative Power Supply
Non-inverting Input
Inverting Input
Output
Positive Power Supply
Description
©
DS21482B-page 4
2002 Microchip Technology Inc.
TC913A/TC913B
3.0
3.1
DETAILED DESCRIPTION
Theory of Operation
3.3
Overload Recovery
Each of the TC913's two Op Amps actually consists of
two amplifiers. A main amplifier is always connected
from the input to the output. A separate nulling amplifier
alternately nulls its own offset and then the offset of the
amplifier. Since each amplifier is continuously being
nulled, offset voltage drift with time, temperature and
power supply variations is greatly reduced.
All nulling circuitry is internal and the nulling operation
is transparent to the user. Offset nulling voltages are
stored on two internal capacitors. An internal oscillator
and control logic, shared by the TC913's two amplifiers,
control the nulling process.
The TC913 recovers quickly from output saturation.
Typical recovery time from positive output saturation is
20 msec. Negative output saturation recovery time is
typically 5 msec.
3.4
Avoiding Latchup
3.2
Pin Compatibility
Junction-isolated CMOS circuits inherently contain a
parasitic p-n-p-n transistor circuit. Voltages exceeding
the supplies by 0.3V should not be applied to the
device pins. Larger voltages can turn the p-n-p-n
device on, causing excessive device power supply
current and power dissipation. The TC913's power
supplies should be established at the same time or
before input signals are applied. If this is not possible,
input current should be limited to 0.1mA to avoid
triggering the p-n-p-n structure.
The TC913 pinout is compatible with OP-14, LM358,
MC1458, LT1013, TLC322, and similar dual Op Amps.
In many circuits operating from single or ±5V supplies,
the TC913 is a drop-in replacement offering DC
performance rivaling that of the best single Op Amps.
The TC913's amplifiers include a low-impedance class
AB output buffer. Some previous CMOS chopper
amplifiers used a high impedance output stage which
made open-loop gain dependent on load resistance.
The TC913's open-loop gain is not dependent on load
resistance.
2002 Microchip Technology Inc.
DS21482B-page 5
©
