AD8556ARZ Analog Devices Inc, AD8556ARZ Datasheet - Page 24

• Manufacturer Part Number: AD8556ARZ
• Description: IC AMP CHOPPER 2MHZ 10MA 8SOIC
• Manufacturer: Analog Devices Inc
• Series: DigiTrim®r
• Type: Instrumentation Amplifierr

Specifications of AD8556ARZ

• Operating Temperature: -40°C ~ 140°C
• Amplifier Type: Chopper (Zero-Drift)
• Number Of Circuits: 1
• Slew Rate: 1.2 V/µs
• Gain Bandwidth Product: 2MHz
• Current - Input Bias: 49nA
• Voltage - Input Offset: 2µV
• Current - Supply: 2mA
• Current - Output / Channel: 10mA
• Voltage - Supply, Single/dual (±): 4.5 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• No. Of Amplifiers: 1
• Bandwidth: 700kHz
• Rail To Rail I/o Type: Rail-Rail I/O
• No. Of Channels: 1
• Supply Voltage Range: 2.7V To 5.5V
• Amplifier Case Style: SOIC
• No. Of Pins: 8
• Number Of Channels: 1
• Number Of Elements: 5
• Power Supply Requirement: Single
• Common Mode Rejection Ratio: 80dB
• Unity Gain Bandwidth Product (typ): 8MHz
• Single Supply Voltage (typ): 5V
• Dual Supply Voltage (typ): Not RequiredV
• Power Supply Rejection Ratio: 109dB
• Rail/rail I/o Type: Rail to Rail Input/Output
• Single Supply Voltage (min): 4.5V
• Single Supply Voltage (max): 5.5V
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Operating Temp Range: -40C to 140C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 8
• Package Type: SOIC N
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Output Type: -
• -3db Bandwidth: -
• Lead Free Status / Rohs Status: Compliant

AD8556
EMI/RFI PERFORMANCE
Real world applications must work with ever increasing
radio/magnetic frequency interference (RFI and EMI). In
situations where signal strength is low and transmission lines
are long, instrumentation amplifiers such as AD8556 are
needed to extract weak, small differential signals riding on
common-mode noise and interference. Additionally, wires and
PCB traces act as antennas and pick up high frequency EMI
signals. The longer the wire, the larger the voltage it picks up.
The amount of voltages picked up is dependent on the
impedances at the wires, as well as the EMI frequency. These
high frequency voltages are then passed into the in-amp
through its pins. All instrumentation amplifiers can rectify high
frequency out-of-band signals. Unfortunately, the EMI/RFI
rectification occurs because amplifiers do not have any
significant common-mode rejection above 100 kHz. Once these
high frequency signals are rectified, they appear as dc offset
errors at the output.
AD8556 features internal EMI filters on the VNEG, VPOS,
FILT and VCLAMP pins. These built-in filters on the pins limit
VNEG
VPOS
FILTER
FILTER
EMI
EMI
FILTER
VSS
EMI
–IN
+IN
LOGIC
DIGIN
1
2
1
2
+IN
–IN
+IN
–IN
VDD
VDD
VSS
VSS
Figure 51. Block Diagram Showing EMI/RFI Built-In Filters
A2
A1
OUT
OUT
3
3
R2
R3
R1
P2
P1
Rev. 0 | Page 24 of 28
VDD
R5
VSS
DAC
R4
AD8556
P3
P4
1
2
+IN
–IN
R6
A3
the interference bandwidth, and provide good RFI suppression
without reducing performance within the pass-band of the
in-amp. A functional diagram of AD8556 along with its
EMI/RFI filters is shown in Figure 51.
AD8556 has built-in filters on its inputs, VCLAMP, and filter
pins. The first-order low-pass filters inside the AD8556 are
useful to reject high frequency EMI signals picked up by wires
and PCB traces outside the AD8556. The most sensitive pin of
any amplifier to RFI/EMI signal is the non-inverting pin. Signals
present at this pin appear as common-mode signals and create
problems.
The filters built at the input of the AD8556 have two different
bandwidths: common and differential mode. The common-
mode bandwidth defines what a common-mode RF signal sees
between the two inputs tied together and ground. The EMI
filters placed on the input pins of the AD8556 reject EMI/RFI
suppressions that appear as common-mode signals.
VCLAMP
R7
VDD
OUT
VSS
3
FILTER
FILT/DIGOUT
EMI
RF
FILTER
2
1
EMI
+IN
–IN
A5
VDD
OUT
VSS
2
1
+IN
–IN
3
VDD
VSS
A4
OUT
3
VOUT