MICREL MIC864YM

MIC864
Dual 350kHz Rail-to-Rail
Operational Amplifier
General Description
Features
The MIC864 is a dual operational amplifier offering smallsize, low-power consumption (33µA/channel typical),
‘greater-than-the-rails’ input capability, and output range
to within 15mV of the supply rails. The MIC864 can be
operated with a single supply of +2.5V to +5.5V or a dualsupply of ±1.25V to ±2.75V, and features an excellent
speed/power ratio with a gain bandwidth product of
350kHz.
The MIC864 was designed with input stage
transconductance normalization, making it immune to
common-mode rejection ratio (CMRR) and power supply
rejection ratio (PSRR) degradation across the input
voltage range. This feature makes the MIC864 superior to
some earlier operational amplifiers, in which a region of
the input voltage range was subject to degraded
performance.
The MIC864 is available with an industry standard pin
configuration in an 8-pin SOIC package, and is specified to
operate from −40°C to +125°C junction temperature.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
• 2.5V to 5.5V single or ±1.25V to ±2.75V dual supply
voltage
• 33µA per channel quiescent current
• 350kHz gain bandwidth product
• 0.2V/µs slew rate
• 18mA output drive capability (sink or source)
• 200mV greater-than-the-rails input capability
• Rail-to-rail output (within 15mV)
• 80dB common mode rejection ratio (CMRR)
• 80dB power supply rejection ratio (PSRR)
• 8-pin SOIC Package
Applications
•
•
•
•
Battery-powered equipment
Cellular phone PA biasing circuits
Carbon monoxide detectors
Smoke detectors
_________________________________________________________________________________________________________________________
Pin Configuration
MIC864 8-Pin SOIC (M)
(Top View)
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
March 2012
M9999-032612-A
Micrel, Inc.
MIC864
Ordering Information
Part Number
MIC864YM
Junction Temperature Range
Package
–40°C to +125°C
8-Pin SOIC
Pin Configuration
MIC864 8-Pin SOIC (M)
(Top View)
Pin Description
Pin Number
Pin Name
1
OUTA
Output of operational amplifier A.
2
−INA
Inverting input of operational amplifier A.
3
+INA
Non-inverting input of operational amplifier A.
4
V−
5
+INB
Non-inverting input of operational amplifier B.
6
−INB
Inverting input of operational amplifier B.
7
OUTB
Output of operational amplifier B.
8
V+
March 2012
Pin Function
Negative Power Supply Connection. Connect to GND for single supply operation.
Positive Power Supply Input. Connect a 0.1µF ceramic bypass capacitor from V+ to V−, placed within
0.2in (5mm) of the MIC864.
2
M9999-032612-A
Micrel, Inc.
MIC864
Absolute Maximum Ratings(1)
Operating Ratings(2)
Supply Voltage (V+ to V−)...........................................+6.0V
Differential Input Voltage (|V+IN − V-IN|)........................+6.0V
Input Voltage (V+IN, V−IN) ............... (V+) + 0.2V, (V−) − 0.2V
Output Short-Circuit Duration............................. Continuous
Lead Temperature (soldering, 10s)............................ 260°C
Storage Temperature (TS).........................−65°C to +150°C
Junction Temperature (TJ) ........................−40°C to +150°C
ESD Rating(3) ................................................. ESD Sensitive
Supply Voltage (V+ to V−)............................ +2.5V to +5.5V
Differential Input Voltage (|V+IN − V-IN_|)........ +2.5V to +5.5V
Input Voltage (V+IN, V−IN) .................(V+) + 0.2V, (V−) − 0.2V
Ambient Temperature (TA) ........................ –40°C to +125°C
Package Thermal Resistance
SOIC-8 (θJA).......................................................99°C/W
Electrical Characteristics(4)
V+ = +2.5V, V− = −2.5V, VCM = ((V+) – (V-))/2; RL = 100kΩ connected to ((V+) – (V−))/2; TJ = +25°C, unless otherwise noted.
Bold values indicate –40°C ≤ TJ ≤ +125°C.
Symbol
VOS
Parameter
Condition
Min.
Typ.
Max.
Units
Input Offset Voltage
2
8
mV
Input Offset Voltage
Temperature Coefficient
4
µV/°C
IB
Input Bias Current
±2.5
±20
pA
IOS
Input Offset Current
±0.5
±15
pA
VCM
Input Voltage Range
(V+) + 0.2
V
(V−) − 0.2
CMRR
Common-Mode Rejection
Ratio
(V−) − 0.2V < VCM < (V+) + 0.2V
PSRR
Power Supply Rejection
Ratio
AVOL
VOUT
80
dB
2.5 < VS < 5.25V
80
dB
Large-Signal Voltage Gain
CL = 100pF, RL = 100kΩ
80
dB
Maximum Output Voltage
Swing
RL = 100kΩ
(V−) + 0.015
(V+) − 0.015
RL = 5kΩ
(V−) + 0.125
(V+) − 0.125
Gain-Bandwidth Product
CL = 100pF, RL = 100kΩ
350
kHz
SR
Slew Rate
AV = 1, CL = 100pF, RL = 100kΩ
0.2
V/µs
ISC
Short-Circuit Output
Current
Source, RL connected to V−
23
Sink, RL connected to V+
15
IS
Supply Current per
Amplifier
No Load
33
GBW
54
V
mA
50
µA
Notes:
1.
Exceeding the absolute maximum rating may damage the device.
2.
The device is not guaranteed to function outside its operating rating.
3.
Devices are ESD Sensitive. Handling precautions recommended. Human body model, 1.5kΩ in series with 100pF.
4.
Specification for packaged product only.
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Micrel, Inc.
MIC864
Typical Characteristics
V+ = VS/2 = 2.5V, V− = −VS/2 = −2.5V, RL = 100kΩ , RL and CL connected in parallel to GND; TA = +25°C, unless otherwise noted.
100
45
80
80
80
0
60
60
60
-45
40
-90
20
-135
20
40
20
100k
100000
1M
1000000
10
10
100
100
10k
10000
100
0
60
-45
60
-45
40
-90
40
-90
20
-135
20
-135
-180
0
-180
0
-225
-20
-225
-20
20
-135
GAIN (dB)
-90
PHASE (Degrees)
40
10k
10000
100k 1000000
1M
100000
1
1
10
10
FREQUENCY (Hz)
1k
1000
10k
10000
90
80
SUPPLY CURRENT (µA)
5
4
3.5
3
2.5
2
1.5
=+IN
0V,
Sinking, R
RLTO
to V+
+IN
==
0V,
SINKING,
V+
L
+IN
L TO
+IN == 5V,
5V, SOURCING,
Sourcing, RLRto
V- V10
15
20
OUTPUT CURRENT (mA)
March 2012
100
100
1k
1000
10k
10000
-225
100k
1M
100000 1000000
FREQUENCY (Hz)
Short Circuit Current vs. Supply
Voltage
30
NO LOAD
+IN
= 0V,
Sinking, RRL
to V+
+IN
= 0V,
SINKING,
L TO
DUAL OP AMP
70
60
50
+IN
==
5V,
RLto
TOV-V+IN
5V,SOURCING,
Sourcing, RL
25
SINGLE OP AMP
40
30
20
20
15
10
5
0
0
5
10
10
10
0
0
-180
Gain (5kΩ
GAIN
(5k Ω ||II 100pF)
100pF)
PHASE
(5k Ω|| II100pF)
100pF)
Phase (5kΩ
1
100k 1000000
1M
100000
Supply Current vs. Supply
Voltage
4.5
1
100
100
PHASE
Phase (5k
(5kΩ)
Ω)
FREQUENCY (Hz)
Output Voltage Swing vs.
Output Current
0.5
Open-Loop Gain and Phase
vs. Frequency
80
-45
1k
1000
FREQUENCY (Hz)
0
60
100
100
-225
10k
1M
10000 100k
100000 1000000
80
0
10
10
1k
1000
45
80
1
1
100
100
100
GAIN
(5k Ω)
Gain (5kΩ)
-20
10
10
45
45
Gain (100kΩ
& 100pF)
GAIN
(100k Ω AND
100pF)
PHASE
(100k Ω||II100pF)
100pF)
Phase (100kΩ
11
1M
1000000
Open-Loop Gain and Phase
vs. Frequency
Open-Loop Gain and Phase
vs. Frequency
0
100k
100000
FREQUENCY (Hz)
FREQUENCY (Hz)
100
1k
1000
GAIN (dB)
10k
10000
CURRENT (mA)
1k
1000
PHASE (Degrees)
100
100
PHASE
Phase (100k
(100kΩ)
Ω)
-20
-20
-20
1010
-180
GAIN
Gain (100k
(100kΩ)
Ω)
CMRR (100kΩ || 100pF)
PSRR (100kΩ || 100pF)
GAIN (dB)
0
CMRR (100kΩ)
0
PSRR (100kΩ)
PHASE (Degrees)
40
PHASE (Degrees)
100
GAIN (dB)
100
0
OUTPUT VOLTAGE (V)
Open-Loop Gain and Phase
vs. Frequency
CMRR vs. Frequency
CMRR (dB)
PSRR (dB)
PSRR vs. Frequency
25
30
2
2.5
3
3.5
4
4.5
SUPPLY VOLTAGE (V)
4
5
5.5
2
2.5
3
3.5
4
4.5
5
5.5
SUPPLY VOLTAGE (V)
M9999-032612-A
Micrel, Inc.
MIC864
Functional Characteristics
V+ = VS/2 = 2.5V, V− = -VS/2 = 2.5V, RL = 100kΩ , RL and CL connected in parallel to GND; TA = +25°C, unless otherwise noted.
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MIC864
Functional Characteristics (Continued)
V+ = VS/2 = 2.5V, V− = -VS/2 = 2.5V, RL = 100kΩ , RL and CL connected in parallel to GND; TA = +25°C, unless otherwise noted.
March 2012
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MIC864
Functional Description
The MIC864 is a dual-operational amplifier with an input
range 0.2V greater than the supply rails and an output
range to within 15mV of the supply rails (100kΩ load).
The MIC864 can be operated from a single from 2.5V to
5.5V supply or a dual ±1.25V to ±2.75V supply. It
features a low 33µA quiescent current per channel with
a gain bandwidth product of 350kHz.
Compared with other operational amplifiers in its class,
the MIC864 offers dependable CMRR and PSRR. This is
achieved through transconductance normalization, which
ensures consistent performance across the entire input
voltage range. This feature eliminates a region of the
input voltage range where some earlier operational
amplifiers were subject to degraded CMRR and PSRR.
Transconductance Normalization
Hand-off between the NFET and PFET differential pairs
is managed by the transconductance normalization
circuit block. As the common-mode input voltage
transitions between high and low voltages, this circuit
block ensures smooth, consistent, and continuous
operation.
Class AB Output Stage
Low output impedance is achieved by driving the
common-emitter output stage with a class AB control
circuit. In contrast with the common collector output
stages of earlier operational amplifiers, this allows an
output range very close to the supply rails.
Input Stage
The MIC864 uses parallel NFET and PFET differential
input transistor pairs for a common-mode input voltage
range beyond the supply rails. When input voltages are
high, the NFET differential input pair operates. When
input voltages are low, the PFET differential input pair
operates.
Functional Diagram
MIC864 Block Diagram
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MIC864
Application Information
The MIC864 operational amplifier is optimized for
portable applications such as cell phones, computer
pads, media players, mobile chemical sensors, carbon
monoxide detectors, and smoke detectors. A 2.5V to
5.5V supply voltage range allows operation from the
regulated output of a lithium-ion battery. No-load supply
current is 33µA per channel for long battery life. An input
range 0.2V beyond the supply rails and an output range
to within 15mV of the supply rails (100kΩ load) maximize
dynamic range for improved signal to noise ratios in the
application. High, consistent CMRR and PSRR minimize
power supply noise coupling from adjacent circuitry.
Power Supply Bypassing
For single supply operation, connect a 0.1µF ceramic
capacitor between the V+ and V− power supply pins. For
dual supply operation, connect 0.1µF capacitors from V+
to GND and from GND to V−. Place these capacitors
within 0.2in (5mm) of the MIC864. If no large-value
capacitors are nearby then also include 10uF capacitors
connected in similar fashion.
Capacitive and Resistive Loads
The MIC864 is internally compensated for unity-gain
stability with load resistances between 5kΩ and 100kΩ,
and a 100pF load capacitance. A 68pF minimum load
capacitance is required to ensure unity-gain stability
across production and temperature variations. Care
should be taken to observe the minimum load
capacitance requirement in circuits with a gain less than
2, and in circuits with a capacitor connected between the
IN- and OUT pins.
Input protection
The IN- and IN+ inputs of the MIC864 are clamped to
the V+ and V− pins using ESD protection diodes.
Operation of IN+ or IN− beyond (V+) + 0.2V and (V−) −
0.2V is not recommended as this would turn on the ESD
protection diodes and violates the Absolute Maximum
Ratings.
Driving ADCs
ADCs (analog-to-digital converters) typically include
either a capacitive sample-and-hold or a capacitive DAC
at their inputs. During operation, they periodically
connect those capacitors to their inputs while sampling
the input signal. General practice is to place a RC lowpass filter between the operational amplifier supplying
the input signal and the ADC. The series resistor
between the operational amplifier output and ADC input
limits capacitive loading on the operational amplifier to
prevent instability. The capacitor between the ADC input
and GND minimizes glitches by supplying charge to the
internal ADC capacitors.
Feedback
Feedback resistors in the 5kΩ and 100kΩ range are
recommended. Load resistance and capacitance
requirements must be considered when designing the
feedback network, especially in unity-gain and low-gain
circuits (see “Capacitive and Resistive Loads” section for
further information).
When using high-value feedback resistors, place a lowvalue capacitor in parallel with the resistor connected
between IN- and OUT. This capacitor counteracts the
effects of the parasitic capacitance at the IN- pin which
forms a pole that may otherwise degrade stability.
However, a 68pF minimum load capacitance must be
included to ensure stability.
When AC-coupling signals to the MIC864 through a
capacitor, provide a DC-bias current path using a
resistor. Otherwise, there will be no source for supplying
the input bias current and the circuit will stop working.
March 2012
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Micrel, Inc.
MIC864
Package Information
8-Pin SOIC (M)
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This
information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,
specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual
property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability
whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties
relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
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into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
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© 2012 Micrel, Incorporated.
March 2012
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