The MIC911 is a high-speed operational amplifier which is
unity gain stable regardless of resistive and capacitive load.
It provides a gain-bandwidth product of 105MHz, a very low
1.25mA supply current, and features the Ittybitty™ SOT-23-5
package.
Supply voltage range is from ±2.5V to ±9V, allowing the
MIC911 to be used in low-voltage circuits or applications
requiring large dynamic range.
The MIC911 is stable driving any capacitative load and
achieves excellent PSRR and CMRR, making it much easier
to use than most conventional high-speed devices. Low
supply voltage, low power consumption, and small packing
make the MIC911 ideal for portable equipment. The ability to
drive capacitative loads also makes it possible to drive long
coaxial cables.
Features
• 105MHz gain bandwidth product
• 1.25mA supply current
• Unconditionally unity gain stable
• Drives any capacitive load
• SOT-23-5 package
• 120V/µs slew rate
• 112dB CMRR
• Stable with gain of +2 or –1
Applications
• Video
• Imaging
• Ultrasound
• Portable equipment
• Line drivers
• XDSL
Ordering Information
Part NumberJunction Temp. RangePackage
MIC911BM5–40°C to +85°CSOT-23-5
Pin Configuration
IN+
OUTV+
13
2
Part
Identification
A22
45
IN–
V–
SOT-23-5
Pin Description
Pin NumberPin NamePin Function
1OUTOutput: Amplifier Output
2V+Positive Supply (Input)
3IN+Noninverting Input
4IN–Inverting Input
5V–Negative Supply (Input)
Functional Pinout
IN+
45
IN–
OUTV+
13
2
V–
SOT-23-5
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
June 20001MIC911
Page 2
MIC911Micrel
Absolute Maximum Ratings (Note 1)
Supply Voltage (V
Differentail Input Voltage (V
Input Common-Mode Range (V
Note 1. Exceeding the absolute maximum rating may damage the device.
Note 2. The device is not guaranteed to function outside its operating rating.
Note 3. Exceeding the maximum differential input voltage will damage the input stage and degrade performance (in particular, input bias current is
Note 4. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
Note 5. Output swing limited by the maximum output sink capability, refer to the short-circuit current vs. temperature graph in “Typical Characteristics.”
Input Offset Current2µA
0.033µA
Input Common-Mode RangeCMRR > 60dB–7.5+7.5V
Large-Signal Voltage GainRL = 2kΩ, V
= ±6V6580dB
OUT
Maximum Output Voltage Swingpositive, RL = 2kΩ+7.2+7.4V
+6.8V
negative, R
= 2kΩ–7.4–7.2V
L
Short-Circuit Output Currentsource80mA
sink22mA
Supply Current1.351.9mA
likely to change).
–6.8V
2.4mA
June 20003MIC911
Page 4
MIC911Micrel
c
r
Test Circuits
V
CC
10µF
V
CC
Input
BNC
50Ω
0.1µF
0.1µF
R2
5k
10µF
Input
10k
4
MIC911
3
10k
10k
50Ω
BNC
0.1µF
50Ω
All resistors:
1% metal film
PSRR vs. Frequency
2k
2
5
BNC
1
Output
Input
BNC
R1 5k
R7c 2k
R7b 200Ω
R7a 100Ω
4
MIC911
3
0.1µF
2
5
0.1µF
1
BNC
Output
R6
5k
R3
R4
250Ω
R5
5k
++
5
R7
200k
VV
1
All resistors 1%
R2R1R2 RR4
=++
OUTERROR
1
CMRR vs. Frequency
BNC
To
Dynami
Analyze
0.1µF
10µF
V
EE
100pF
V
CC
R1
20Ω
R5
20Ω
10pF
R3 27k
S1
S2
R4 27k
10pF
R2 4k
4
MIC911
3
10µF
0.1µF
2
5
0.1µF
10µF
V
EE
10µF
V
EE
Noise Measurement
MIC9114June 2000
Page 5
MIC911Micrel
-2.0
-1.5
-1.0
-0.5
0.0
-40 -20 0 20 40 60 80 100
OFFSET VOLTAGE (mV)
TEMPERATURE (°C)
Offset Voltage
vs. Temperature
V
SUPPLY
= ±5V
V
SUPPLY
= ±9V
-1.25
-1.00
-0.75
-0.50
-0.25
-5-4-3-2-1012345
OFFSET VOLTGE (mV)
COMMON-MODE VOLTAGE (V)
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0 20406080
OUTPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
-4.0
-3.5
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
-25-20-15-10-50
OUTPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
Output Voltage
vs. Output Current
+85°C
+25°C
-40°C
SINKING
CURRENT
V
SUPPLY
= ±5V
Electrical Characteristics
Supply Current
vs. Supply Voltage
2.0
+85°C
1.5
1.0
SUPPLY CURRENT (mA)
0.5
2345678910
SUPPLY VOLTAGE (±V)
+25°C
-40°C
Bias Current
vs. Temperature
2.5
2
V
1.5
1
BIAS CURRENT (µA)
V
SUPPLY
0.5
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
SUPPLY
= ±5V
= ±9V
Supply Current
2.0
1.8
1.6
1.4
1.2
SUPPLY CURRENT (mA)
1.0
vs. Temperature
V
= ±9V
SUPPLY
V
= ±5V
SUPPLY
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
Offset Voltage
vs. Common-Mode Voltage
V
= ±5V
SUPPLY
+85°C
+25°C
-40°C
Offset Voltage
vs. Common-Mode Voltage
-0.5
+85°C
-1.0
OFFSET VOLTGE (mV)
-1.5
-8 -6 -4 -2 0 2 4 6 8
COMMON-MODE VOLTAGE (V)
+25°C
V
SUPPLY
-40°C
= ±9V
95
90
85
80
75
70
65
OUTPUT CURRENT (mA)
60
55
-10
-15
-20
June 20005MIC911
-25
OUTPUT CURRENT (mA)
-30
Short-Circuit Current
vs. Temperature
V
= ±9V
SUPPLY
SOURCING
CURRENT
V
= ±5V
SUPPLY
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
Short-Circuit Current
vs. Supply Voltage
-40°C
+25°C
+85°C
SINKING
CURRENT
2345678910
SUPPLY VOLTAGE (±V)
Short-Circuit Current
vs. Temperature
-10
-15
-20
-25
OUTPUT CURRENT (mA)
-30
-40 -20 0 20 40 60 80 100
V
= ±5V
SUPPLY
SINKING
CURRENT
V
= ±9V
SUPPLY
TEMPERATURE (°C)
Output Voltage
vs. Output Current
+85°C
V
= ±5V
SUPPLY
-40°C
+25°C
SOURCING
CURRENT
Short-Circuit Current
vs. Supply Voltage
100
80
+25°C
60
40
OUTPUT CURRENT (mA)
20
2345678910
SUPPLY VOLTAGE (±V)
-40°C
+85°C
SOURCING
CURRENT
Page 6
MIC911Micrel
(
)
(
)
(
)
(
)
Output Voltage
vs. Output Current
10
9
+85°C
8
7
6
5
4
3
2
OUTPUT VOLTAGE (V)
SOURCING
1
CURRENT
0
0 20406080100
OUTPUT CURRENT (mA)
-40°C
V
SUPPLY
= ±9V
+25°C
Gain Bandwidth and
Phase Margin vs. Load
175
V
150
125
100
75
50
25
GAIN BANDWIDTH (MHz)
0
0200 400 600 800 1000
CAPACITIVE LOAD (pF)
SUPPLY
Phase
Margin
Gain
Bandwidth
= ±9V
46
44
°
42
40
38
36
PHASE MARGIN
34
32
Output Voltage
vs. Output Current
0
-2
-4
-6
-8
OUTPUT VOLTAGE (V)
-10
-30-20-100
+25°C
+85°C
V
SUPPLY
OUTPUT CURRENT (mA)
= ±9V
SINKING
CURRENT
-40°C
Gain Bandwidth and
Phase Margin vs. Supply Voltage
175
150
125
100
75
50
25
GAIN BANDWIDTH (MHz)
0
2345678910
SUPPLY VOLTAGE (±V)
Phase
Margin
Gain
Bandwidth
46
44
°
42
40
38
36
PHASE MARGIN
34
32
Gain Bandwidth and
Phase Margin vs. Load
175
V
150
125
100
75
50
25
GAIN BANDWIDTH (MHz)
0
0200 400 600 800 1000
CAPACITIVE LOAD (pF)
SUPPLY
Phase
Margin
Gain
Bandwidth
= ±5V
Common-Mode
120
100
CMRR (dB)
Rejection Ratio
80
60
V
= ±5V
40
20
0
SUPPLY
1x1021x1031x1041x1051x1061x10
FREQUENCY (Hz)
46
44
°
42
40
38
36
PHASE MARGIN
34
32
7
Common-Mode
120
100
CMRR (dB)
Rejection Ratio
80
V
60
40
20
0
1x1021x1031x1041x1051x1061x10
= ±9V
SUPPLY
FREQUENCY (Hz)
Positive Power Supply
100
+PSRR (dB)
Rejection Ratio
80
60
40
20
0
V
= ±9V
SUPPLY
1x1021x1031x1041x1051x1061x10
FREQUENCY (Hz)
Positive Power Supply
100
+PSRR (dB)
7
Rejection Ratio
80
60
40
20
0
V
= ±5V
SUPPLY
1x1021x1031x1041x1051x1061x10
FREQUENCY (Hz)
7
Negative Power Supply
100
–PSRR (dB)
7
Rejection Ratio
80
60
40
20
0
V
= ±9V
SUPPLY
1x1021x1031x1041x1051x1061x10
FREQUENCY (Hz)
7
Negative Power Supply
100
–PSRR (dB)
Rejection Ratio
80
60
40
20
0
V
= ±5V
SUPPLY
1x1021x1031x1041x1051x1061x10
FREQUENCY (Hz)
Closed-Loop
Frequency Response
10
8
6
4
2
PHASE
0
-2
GAIN (dB)
-4
-6
-8
-10
110100 200
GAIN
±2.5V
±5V
FREQUENCY (MHz)
±9V
7
180
135
90
45
0
-45
-90
-135
-180
-225
-270
°
PHASE
MIC9116June 2000
Page 7
MIC911Micrel
-50
-40
-30
-20
-10
0
10
20
30
40
50
110100 200
GAIN (dB)
FREQUENCY (MHz)
(
)
y
(
)
-10
-8
-6
-4
-2
0
2
4
6
8
10
110100 200
GAIN (dB)
FREQUENCY (MHz)
0
25
50
75
100
0200 400 600 800 1000
SLEW RATE (V/µs)
LOAD CAPACITANCE (pF)
0
50
100
150
0200 400 600 800 1000
SLEW RATE (V/µs)
LOAD CAPACITANCE (pF)
Open-Loop Frequency
Response vs. Capacitive Load
50
V
= ±5V
SUPPLY
40
30
20
10
0
1000pF
-10
GAIN (dB)
470pF
-20
-30
-40
-50
200pF
110100 200
FREQUENCY (MHz)
100pF
Open-Loop
Frequency Response
50
40
30
20
10
0
-10
GAIN (dB)
-20
-30
-40
V
SUPPLY
-50
110100 200
RL= 100Ω
No Load
= ±9V
FREQUENCY (MHz)
50pF
0pF
225
180
135
90
45
0
-45
-90
-135
-180
-225
°
PHASE
Open-Loop Frequency
Response vs. Capacitive Load
V
= ±9V
SUPPLY
50pF
100pF
0pF
1000pF
470pF
200pF
Closed-Loop
Frequency Response
200pF
100pF
50pF
0pF
V
SUPPLY
A
= 1
500pF
1000pF
= ±2.5V
Open-Loop
Frequenc
50
40
30
20
10
0
-10
GAIN (dB)
-20
-30
-40
V
SUPPLY
-50
110100 200
Response
RL= 100Ω
No Load
= ±5V
FREQUENCY (MHz)
Closed-Loop
Frequency Response
10
8
6
4
2
0
-2
GAIN (dB)
-4
-6
-8
-10
110100 200
500pF
1000pF
V
= ±5V
SUPPLY
AV = 1
FREQUENCY (MHz)
200pF
100pF
50pF
0pF
225
180
135
90
45
0
-45
-90
-135
-180
-225
°
PHASE
10
8
6
4
2
0
-2
GAIN (dB)
-4
V
-6
AV = 1
-8
-10
110100 200
Frequency Response
June 20007MIC911
RF
Closed-Loop
Frequency Response
200pF
100pF
50pF
500pF
1000pF
= ±9V
SUPPLY
FREQUENCY (MHz)
Closed-Loop
Test Circuit
V
CC
10µF
0.1µF
MIC911
50Ω
10µF
V
EE
0pF
FET probe
C
L
Positive
Slew Rate
VCC = ±5V
Positive
Slew Rate
VCC = ±9V
Negative
100
75
50
25
SLEW RATE (V/µs)
0
0200 400 600 800 1000
Slew Rate
VCC = ±5V
LOAD CAPACITANCE (pF)
Negative
150
100
50
SLEW RATE (V/µs)
0
0200 400 600 800 1000
Slew Rate
VCC = ±9V
LOAD CAPACITANCE (pF)
Page 8
MIC911Micrel
Voltage
250
Hz
200
nV
150
100
50
NOISE VOLTAGE
0
1x1011x1021x1031x1041x10
Noise
5
FREQUENCY (Hz)
7
6
Hz
5
pA
4
3
2
1
NOISE CURRENT
0
1x1011x1021x1031x1041x10
Current
Noise
5
FREQUENCY (Hz)
MIC9118June 2000
Page 9
MIC911Micrel
Small-Signal
Pulse Response
VCC = ±5V
A
V
= 1
C
L
= 100pF
R
L
= 10MΩ
OUTPUTINPUT
Small-Signal
Pulse Response
VCC = ±9V
A
V
= 1
C
L
= 1.7pF
R
L
= 10MΩ
OUTPUTINPUT
Small-Signal
Pulse Response
VCC = ±9V
A
V
= 1
C
L
= 1000pF
R
L
= 10MΩ
OUTPUTINPUT
Small-Signal
Pulse Response
VCC = ±5V
= 1
A
V
= 1.7pF
C
L
= 10MΩ
R
L
OUTPUTINPUT
Small-Signal
Pulse Response
OUTPUTINPUT
VCC = ±9V
= 1
A
V
= 100pF
C
L
= 10MΩ
R
L
Small-Signal
Pulse Response
VCC = ±5V
= 1
A
V
= 1000pF
C
L
OUTPUTINPUT
June 20009MIC911
Page 10
MIC911Micrel
OUTPUT
OUTPUT
Large-Signal
Pulse Response
∆V = 5.44V
∆t = 42ns
Large-Signal
Pulse Response
∆V = 5.32V
∆t = 100ns
VCC = ±5V
= 1
A
V
= 1.7pF
C
L
= 10MΩ
R
L
VCC = ±5V
= 1
A
V
= 1000pF
C
L
= 10MΩ
R
L
OUTPUT
OUTPUT
Large-Signal
Pulse Response
∆V = 5.52V
∆t = 46ns
Large-Signal
Pulse Response
∆V = 5.52V
∆t = 34ns
VCC = ±5V
= 1
A
V
= 100pF
C
L
= 10MΩ
R
L
VCC = ±9V
= 1
A
V
= 1.7pF
C
L
= 10MΩ
R
L
OUTPUT
Large-Signal
Pulse Response
∆V = 5.24V
∆t = 36ns
VCC = ±9V
= 1
A
V
= 100pF
C
L
= 10MΩ
R
L
OUTPUT
Large-Signal
Pulse Response
∆V = 5.56V
∆t = 84ns
VCC = ±9V
= 1
A
V
= 1000pF
C
L
= 10MΩ
R
L
MIC91110June 2000
Page 11
MIC911Micrel
PVVI
DVV
S
(no load)
=−
()
+−
Total Power DissipationPP
DDt
=+
(no load)(outpu stage)
Applications Information
The MIC911 is a high-speed, voltage-feedback operational
amplifier featuring very low supply current and excellent
stability. This device is unity gain stable and capable of
driving high capacitance loads.
Driving High Capacitance
The MIC911 is stable when driving any capacitance (see
“Typical Characteristics: Gain Bandwidth and Phase Margin
vs. Load Capacitance”) making it ideal for driving long coaxial
cables or other high-capacitance loads.
Phase margin remains constant as load capacitance is
increased. Most high-speed op amps are only able to drive
limited capacitance.
Note: increasing load capacitance does reduce the
speed of the device (see “Typical Characteristics: Gain Bandwidth and Phase Margin vs.
Load”). In applications where the load capacitance reduces the speed of the op amp to an
unacceptable level, the effect of the load capacitance can be reduced by adding a small resistor
(<100Ω) in series with the output.
Feedback Resistor Selection
Conventional op amp gain configurations and resistor selection apply, the MIC911 is NOT a current feedback device.
Resistor values in the range of 1k to 10k are recommended.
Layout Considerations
All high speed devices require careful PCB layout. The high
stability and high PSRR of the MIC911 make this op amp
easier to use than most, but the following guidelines should
be observed: Capacitance, particularly on the two inputs pins
will degrade performance; avoid large copper traces to the
inputs. Keep the output signal away from the inputs and use
a ground plane.
It is important to ensure adequate supply bypassing capacitors are located close to the device.
Power Supply Bypassing
Regular supply bypassing techniques are recommended. A
10µF capacitor in parallel with a 0.1µF capacitor on both the
positive and negative supplies are ideal. For best performance all bypassing capacitors should be located as close to
the op amp as possible and all capacitors should be low ESL
(equivalent series inductance), ESR (equivalent series resistance). Surface-mount ceramic capacitors are ideal.
Thermal Considerations
The SOT-23-5 package, like all small packages, has a high
thermal resistance. It is important to ensure the IC does not
exceed the maximum operating junction (die) temperature of
85°C. The part can be operated up to the absolute maximum
temperature rating of 125°C, but between 85°C and 125°C
performance will degrade, in particular CMRR will reduce.
A MIC911 with no load, dissipates power equal to the quiescent supply current * supply voltage
When a load is added, the additional power is dissipated in
the output stage of the op amp. The power dissipated in the
device is a function of supply voltage, output voltage and
output current.
PVVI
DV
(output stage)
=−
()
+
OUT OUT
Ensure the total power dissipated in the device is no greater
than the thermal capacity of the package. The SOT23-5
package has a thermal resistance of 260°C/W.
Max Allowable Power Dissipation
.=
TT
−
JA
(max)(max)
260W
June 200011MIC911
Page 12
MIC911Micrel
Package Information
1.90 (0.075) REF
0.95 (0.037) REF
3.02 (0.119)
2.80 (0.110)
0.50 (0.020)
0.35 (0.014)
1.75 (0.069)
1.50 (0.059)
1.30 (0.051)
0.90 (0.035)
0.15 (0.006)
0.00 (0.000)
SOT-23-5 (M5)
3.00 (0.118)
2.60 (0.102)
10°
0°
DIMENSIONS:
MM (INCH)
0.20 (0.008)
0.09 (0.004)
0.60 (0.024)
0.10 (0.004)
MICREL INC. 1849 FORTUNE DRIVESAN JOSE, CA 95131 USA
TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB http://www.micrel.com
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.