1
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
10/99
CALIFORNIA MICRO DEVICES
CMC7106
Features
Tiny SOT23-6 package
Guaranteed specs at 2.7V, 3V, and 5V
Low supply current 0.3A typ. operating. Less
than 1A idle.
Rail-to-Rail Input and Output (RRIO)
Simple shutdown mode (with logic level control)
for power savings
1MHz gain-bandwidth
Input common mode range includes V- and V+
Applications
Test and Measurement Equipment
Cellular Phones
Portable Equipment
Notebooks and PDAs
Electronic Toys
C0600999
T
S
R
A
D
N
A
N
O
I
T
A
M
R
O
F
N
I
G
N
I
R
E
D
R
O
T
R
A
P
D
e
g
a
k
c
a
P
r
e
b
m
u
N
t
r
a
P
g
n
ir
e
d
r
O
s
n
i
P
e
l
y
t
S
l
e
e
R
&
e
p
a
T
g
n
i
k
r
a
M
t
r
a
P
6
6
-
3
2
T
O
S
R
/
Y
6
0
1
7
C
M
C
6
0
1
7
CONNECTION DIAGRAM
Product Description
The California Micro Devices CMC7106 is a high performance CMOS operational amplifier in a 6-pin SOT23-6 package.
Operating with low supply current, it is ideal for battery operated applications where power, space, and weight are critical
considerations.
Performance is similar to CAMDs CMC7101AY SOT Amp, with the addition of a shutdown pin to greatly reduce supply
current when idle. The shutdown mode is controlled by an extra pin, and is compatible with most logic family signal
levels.
Ideal for use in test and measurement equipment and personal electronics such as cellular handsets, pagers, cordless
telephones, and other products with limited space and battery power.
CMC7106 Low Power Operational Amplifier,
RRIO, with Shutdown, SOT23-6
10/99
2
CALIFORNIA MICRO DEVICES
CMC7106
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
Note 1
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating conditions indicate ratings for which the
device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the
Electrical Operating Characteristics.
Note 2
Human body model, 1.5K in series with 100pF.
Note 3
Applies to both single-supply and split-supply operation. Continuous short circuit operation at elevated ambient temperatures can result in
exceeding the maximum allowed junction temperature of 150C.
Note 4
The maximum power dissipation is a function of T
J(MAX)
,
JA
, and T
A.
The maximum allowable power dissipation at any ambient temperature
is PD = (T
J(MAX)
- T
A
)/
JA
. All numbers apply for packages soldered directly to a PC board.
)
1
e
t
o
N
(
S
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(
,
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)
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)
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r
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)
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7
.
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V < 7
V
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p
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T
n
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0
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< T
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<
5
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+
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e
R
l
a
m
r
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h
T
q
A
J
)
5
2
3
o
W
/
C
3
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
10/99
CALIFORNIA MICRO DEVICES
CMC7106
S
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if
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p
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0
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if
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t
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R
w
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.
0
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H
M
10/99
4
CALIFORNIA MICRO DEVICES
CMC7106
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
S
C
I
T
S
I
R
E
T
C
A
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A
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C
G
N
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T
A
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m
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s
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t
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l
n
U
J
R
,
V
0
=
-
V
,
V
3
=
+
V
,
C
5
2
=
L
M
1
>
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1
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=
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8
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=
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1
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R
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t
a
R
w
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l
S
0
7
.
0
/
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W
B
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d
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a
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0
6
.
0
z
H
M
5
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
10/99
CALIFORNIA MICRO DEVICES
CMC7106
S
C
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T
S
I
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E
T
C
A
R
A
H
C
G
N
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T
A
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5
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n
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il
ll
a
,
d
e
if
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s
i
w
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h
t
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s
s
e
l
n
U
J
R
,
V
0
=
-
V
,
V
5
=
+
V
,
C
5
2
=
L
M
1
>
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10/99
6
CALIFORNIA MICRO DEVICES
CMC7106
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
CONNECTION DIAGRAMS
TYPICAL PERFORMANCE CHARACTERISTICS
7
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
10/99
CALIFORNIA MICRO DEVICES
CMC7106
TYPICAL PERFORMANCE CHARACTERISTICS
10/99
8
CALIFORNIA MICRO DEVICES
CMC7106
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
TYPICAL PERFORMANCE CHARACTERISTICS
9
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
10/99
CALIFORNIA MICRO DEVICES
CMC7106
TYPICAL PERFORMANCE CHARACTERISTICS
10/99
10
CALIFORNIA MICRO DEVICES
CMC7106
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
Application Benefits
The CMC7106 is very similar to the CAMD CMC7101AY,
an improved version of the industry standard 7101 op
amp. The CMC7106 has the additional benefit of reducing
power consumption to almost nothing (<5microWatts @
5V) when the amplifier is not being used.
Packaging
Most of the benefits of the CMC7106 are due to the use of
a SOT package. The industry has readily adopted the SOT23-
5 footprint, and this similar version has six pins. This leads
to smaller finished products.
PC CARDS (PCMCIA type III cards) require low profile components.
At 0.056 inches (1.43 mm), the CMC7106 is ideal.
Signal Integrity
As products become smaller, the natural space used to
isolate circuits is lost. Signals can interact or pick up noise
in these designs. By using a physically smaller amplifier
package, the CMC7106 can be placed closer to the signal
source, reducing noise pickup and its small size makes it a
simple buffer.
Rail-to-Rail Input and Output allow the amplifier to operate
from lower supplies and also maintain signal level swings
under large signal amplitude conditions.
Simplified Board Layout
Board layout is helped in a couple of ways due to the
small size. Op Amps can be placed where amps are
needed, shortening signal paths and PCB traces subject
to noise pick up. Compared to a dual or quad device,
two or four strategically placed SOT Amps reduce cross-
talk and avoid long traces.
Lower Power Supply Current Drain
The CAMD CMC7106 is similar to the CAMD CMC7101AY,
which has lower power supply drain than other SOT Amps.
The CMC7106 lower supply current means longer operation
in battery operated products, and even further savings in a
shutdown to idle mode.
Higher Output Drive
The CAMD CMC7106 has higher output current than other
SOT Amps. It can be used as a driver in addition to use as
a signal level amplifier.
Rail-To-Rail Input Swing
When the amplifier is used as a buffer, the input of the
amplifier follows the input signal and if this is large
compared to the available supply voltage, it is important
that the Op Amp has a wide CMVR (Common Mode Voltage
Range). RRIO Op Amps have a CMVR equal to (or greater
than) the supplies and this allows large signal swings
without clipping or distortion.
Shutdown Operation
Compared to a typical SOT Amp, an additional pin,
Shutdown, is used to control the idle mode of the
amplifier. It allows the amplifier to be placed in a very low
power consumption mode, effectively reducing the current
to less than 5 W (at 5V supply).
To use the shutdown pin, a logic level signal is connected
to the shutdown pin, which is configured as a digital input
(Logic 1 turns the amplifier on). This makes the input
directly compatible with common logic family parts. If the
shutdown feature is not desired, the pin should be shorted
to V+ (pin 4).
Turn On and Turn Off (Shutdown) Characteristics
The turn off delay, t
OFF
, is defined as the time between the
Shutdown signal crossing and the disable threshold (typically
V+ - 1 volt) and the time for the amplifiers output to
come within 10% of its final value. It is largely governed
by a propagation delay within the CMC7106 of a few
hundred nanoseconds followed by an exponential decay
determined by the load resistance in parallel with the load
capacitance.
The turn on delay, t
ON
, is defined as the time between the
Shutdown signal crossing the threshold and the time the
output reaches to within 10% of its final value. It exhibits
a larger propagation delay through the amplifier which
increases as V+ decreases (see the typical Performance
Characteristics). The delay is followed by output slewing
to the final value.
The delay time for V+ equal to 5 volts is about 4 S, and
since the slew rate is 1V/S, a five volt signal requires about
10 S to reach its final value. With V+ equal to 3 volts,
however, the propagation delay increases to 20 S yielding
a total turn-on time of 24 S for a 3 volt signal.
11
1999 California Micro Devices Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
10/99
CALIFORNIA MICRO DEVICES
CMC7106
High Side Current Sense
To monitor a load current, it is necessary to insert a current
sense resistor into the power supply feed, as shown in
Figure 1. The resulting voltage drop is proportional to the
load current, but as both ends of this resistor are at (or
very near to) the supply voltage, it is difficult to use a
conventional Op Amp.
The CMC7106 is ideal for this application as the inputs
can operate at either supply rail (or at ground when used
with a single supply). The output voltage is directly
proportional to current in the load, scaled by the gain of
the amplifier. To reduce the power loss in the sense resistor
and also keep the supply voltage to the load immune to
load current variations, a small value R
sense
is used.
An excellent application for this circuit is in a battery charger,
where the charging current is monitored to detect end of
charge (battery current will rise as the
cells top off), and charging must be reduced to prevent
damage (out gassing or over heating).
The sense resistor can be placed in the negative side (known
as Low Side Sensing), however this is less desirable due to
disruption of the ground path.
Low Current 3.3V Regulator with Disable
Over the past few years, power supply voltages in systems,
particularly in PCs, have migrated from 5 volts to 3.3 volts
while at the same time, saving power particularly in portable
systems has become a major issue. On the other hand, there
are legacy devices which still mandate the use of a 5 volt V
cc
.
Frequently in systems, a finite amount of current is needed for
the 3.3 volt ICs. The circuit shown below provides a stable 3.3
voltage supply derived from the 5 volts at currents up to 100
Applications of the CMC7106
Figure 1. High Side Current Sense
(1)
Figure 2. 5V to 3.3V Regulator with Disable
mA while drawing only 300 As when enabled. It takes advantage
of the CMC7106 op amp which provides a power down disable
(shutdown) compatible with all 5 volt logic families and an ultra
low current reference, the LT1389. When disabled, the circuit
draws essentially zero current but when enabled exhibits load
regulation of 0.05% from 0 to 100 mA, and line regulation of
0.01% from 4.5 V < Vdd < 5.5 V.
Input Common Mode Range Considerations
The CMC7106 is capable of accommodating input common
mode and output voltages equal to both power supply rails.
Nor will voltages that exceed the supply voltages cause phase
inversion of the output. However, ESD diode clamps are
provided at the inputs that can be damaged if static currents
in excess of 5 mA are allowed to flow through them. This
can occur when the magnitude of input voltage exceeds the
rail by more than 0.3 volt. To preclude damage, a current
limiting resistor, R
s
, in series with the input is recommended
as illustrated in Figure 1, whose value for R
s
is given by:
V
in
- (V+ 0.3 V)
R
s
>
5 mA
For V+ (or V-) equal to 2.7 volts and V
in
equal to 10
volts, Rs should be chosen for a value of 1.5 K or
greater.
Shut-down Pin Current Limiting Considerations
The Shut-down pin also provides ESD clamp diodes that will
be damaged if the signal exceeds the rail by 0.3 volt either
from a logic gate or other signal source. If possible, the current
should be limited to less than 5 mA by inserting a resistor
between the gate or source and the Shut-down Pin whose
value is determined by Equation (1) above.
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