AD8132ARMZ Analog Devices Inc, AD8132ARMZ Datasheet - Page 21

• Manufacturer Part Number: AD8132ARMZ
• Description: IC AMP DIFF LDIST LP 70MA 8MSOP
• Manufacturer: Analog Devices Inc
• Type: Differential Ampr

Specifications of AD8132ARMZ

• Amplifier Type: Differential
• Number Of Circuits: 1
• Output Type: Differential
• Slew Rate: 1200 V/µs
• -3db Bandwidth: 360MHz
• Current - Input Bias: 3µA
• Voltage - Input Offset: 1000µV
• Current - Supply: 12mA
• Current - Output / Channel: 70mA
• Voltage - Supply, Single/dual (±): 2.7 V ~ 11 V, ±1.35 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Number Of Channels: 1
• Number Of Elements: 1
• Power Supply Requirement: Single/Dual
• Common Mode Rejection Ratio: 70dB
• Voltage Gain Db: 0.129dB
• Input Resistance: 3@5VMohm
• Input Offset Voltage: 3.5@5VmV
• Input Bias Current: 7@5VnA
• Single Supply Voltage (typ): 3/5/9V
• Dual Supply Voltage (typ): ±3/±5V
• Power Supply Rejection Ratio: 70dB
• Power Dissipation: 250mW
• Rail/rail I/o Type: No
• Single Supply Voltage (min): 2.7V
• Single Supply Voltage (max): 11V
• Dual Supply Voltage (min): ±1.35V
• Dual Supply Voltage (max): ±5.5V
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 8
• Package Type: MSOP
• No. Of Amplifiers: 1
• Gain Db Max: 1.015dB
• Bandwidth: 350MHz
• Supply Voltage Range: ± 1.35V To ± 5.5V
• Supply Current: 10.7mA
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Gain Bandwidth Product: -
• Lead Free Status / Rohs Status: Compliant

OPERATIONAL DESCRIPTION
DEFINITION OF TERMS
Differential Voltage
It is the difference between two node voltages. For example, the
output differential voltage (or equivalently output differential
mode voltage) is defined as
where V
−OUT terminals with respect to a common reference.
Common-Mode Voltage
It is the average of two node voltages. The output common-
mode voltage is defined as
BASIC CIRCUIT OPERATION
One of the more useful and easy to understand ways to use the
AD8132 is to provide two equal ratio feedback networks. To
match the effect of parasitics, comprise these networks of two
equal value feedback resistors (R
resistors (R
Like a conventional op amp, the AD8132 has two differential
inputs that can be driven with both differential mode input
voltage (V
There is another input to consider (V
is not present on conventional op amps. V
separate from the previous inputs.
There are two complementary outputs whose response can be
defined by a differential mode output (V
mode output (V
Table 10 shows the gain from any type of input to either type
of output.
V
V
OUT, dm
OUT, cm
V
+OUT
+D
OCM
–D
IN, dm
IN
IN
G
= (V
). This circuit is shown in Figure 64.
= (V
and V
) and common-mode input voltage (V
R
R
OUT, cm
+OUT
+OUT
G
G
−OUT
Figure 64. Circuit Definitions
+ V
− V
).
refer to the voltages at the +OUT and
+IN
–IN
−OUT
−OUT
AD8132
)/2
)
C
C
R
R
F
F
F
F
F
) and two equal value gain
–OUT
+OUT
OCM
) on the AD8132 that
OUT, dm
R
OCM
L, dm
is completely
) and a common-
V
OUT, dm
IN, cm
).
Rev. I | Page 21 of 32
Table 10. Differential and Common-Mode Gains
Input
V
V
V
As listed in Table 10, the differential output (V
the differential input voltage (V
does not matter if both differential inputs are driven, or only one
output is driven and the other is tied to a reference voltage, such
as ground. As seen from the two zero entries in the V
neither of the common-mode inputs has any effect on this gain.
The gain from V
depend on the ratio matching of the feedback networks. The
common-mode feedback loop within the AD8132 provides a
corrective action to keep this gain term minimized. The term
balance error describes the degree that this gain term differs
from 0.
The gain from V
of the feedback networks. The analogous term for this transfer
function (used in conventional op amps) is common-mode
rejection ratio (CMRR). Therefore, if it has a high CMRR, the
feedback ratios must be well matched.
The gain from V
independent of the feedback ratio matching. As in the case of
V
term minimized.
The gain from V
are matched only. The amount of differential output signal that is
created by varying V
feedback networks.
V
unity-gain transfer function. With equal ratio feedback networks
(as previously assumed), its effect on each output is the same,
that is the gain from V
output common-mode voltage is set with an internal voltage
divider to a level that is nominally midsupply. It is recommended
that a 0.1 μF bypass capacitor be connected to V
When unequal feedback ratios are used, the two gains associated
with V
mathematical analysis along with any intuitive understanding of
how the part operates.
IN, dm
IN, cm
OCM
IN, dm
OCM
controls the output common-mode voltage V
to V
OUT, dm
OUT, cm
become nonzero. This significantly complicates the
OCM
, the common-mode feedback loop keeps this
IN, cm
IN, dm
IN, cm
V
R
0
0
F
OUT, dm
to V
OCM
/R
to V
to V
to V
G
OCM
is related to the degree of mismatch in the
OUT, dm
OUT, dm
OUT, cm
OUT, cm
to V
is ideally 0 when the feedback ratios
directly depends on the matching
OUT, dm
IN, dm
is ideally 0 and is first-order
is 0, and first-order, does not
) times R
is 0. If not driven, the
V
0 (by design)
0 (by design)
1 (by design)
OUT, cm
F
/R
OUT, dm
G
OCM
. In this case, it
OUT, dm
OUT, cm
.
AD8132
) is equal to
column,
with a