AD210 ,Precision, Wide Bandwidth 3-Port Isolation AmplifierSPECIFICATIONS(typical @ +258C, and V = +15 V unless otherwise noted)SOUTLINE DIMENSIONSModel AD210 ..
AD210AN ,Precision, Wide Bandwidth 3-Port Isolation Amplifierapplications. The AD210 will maintain its highperformance under sustained common-mode stress.Three- ..
AD210BN ,Precision, Wide Bandwidth 3-Port Isolation AmplifierSPECIFICATIONS(typical @ +258C, and V = +15 V unless otherwise noted)SOUTLINE DIMENSIONSModel AD210 ..
AD210JN ,Precision, Wide Bandwidth 3-Port Isolation AmplifierFEATURESHigh CMV Isolation: 2500 V rms Continuous63500 V Peak Continuous INPUT OUTPUT16FBT1Small Si ..
AD210JN ,Precision, Wide Bandwidth 3-Port Isolation Amplifierfeatures proprietary ESD protection circuitry, per-3A reduced signal swing is recommended when both ..
AD215AY ,120 kHz Bandwidth, Low Distortion, Isolation Amplifierspecifications are pre-served and to maintain the isolated supply full load ripple below the specif ..
AD8403AR50 ,1-/2-/4-Channel Digital PotentiometersSpecifications Apply to All VRs2Resistor Differential NL R-DNL R , V = NC –1 ±1/4 +1 LSBWB A2Resist ..
AD8403AR50 ,1-/2-/4-Channel Digital PotentiometersGENERAL DESCRIPTIONCK SHDNRS AGND4The AD8400/AD8402/AD8403 provide a single, dual or quadchannel, 2 ..
AD8403AR-50 ,1-/2-/4-Channel Digital PotentiometersSpecifications Apply to All VRsResolution N 8 Bits4Integral Nonlinearity INL –2 ±1/2 +2 LSB4Differe ..
AD8403ARU1 ,1-/2-/4-Channel Digital PotentiometersFEATURES FUNCTIONAL BLOCK DIAGRAM256 PositionReplaces 1, 2 or 4 PotentiometersRDAC11 kV, 10 kV, 50 ..
AD8403ARU10 ,1-/2-/4-Channel Digital PotentiometersSpecifications Apply to All VRs2Resistor Differential NL R-DNL R , V = NC –1 ±1/4 +1 LSBWB A2Resist ..
AD8403ARU100 ,1-/2-/4-Channel Digital PotentiometersSpecifications Apply to All VRs2Resistor Differential NL R-DNL R , V = NC –1 ±1/4 +1 LSBWB A2Resist ..
AD210
Precision, Wide Bandwidth 3-Port Isolation Amplifier
FUNCTIONAL BLOCK DIAGRAMPrecision, Wide Bandwidth
3-Port Isolation Amplifier
FEATURES
High CMV Isolation:2500V rms Continuous63500
V Peak Continuous
Small Size: 1.00" 3 2.10" 3 0.350"
Three-Port Isolation: Input, Output, and Power
Low Nonlinearity: 60.012% max
Wide Bandwidth: 20kHz Full-Power (–3dB)
Low Gain Drift: 625ppm/8C max
High CMR: 120dB (G = 100V/V)
Isolated Power: 615V @ 65mA
Uncommitted Input Amplifier
APPLICATIONS
Multichannel Data Acquisition
High Voltage Instrumentation Amplifier
Current Shunt Measurements
Process Signal Isolation
GENERAL DESCRIPTIONThe AD210 is the latest member of a new generation of low
cost, high performance isolation amplifiers. This three-port,
wide bandwidth isolation amplifier is manufactured with sur-
face-mounted components in an automated assembly process.
The AD210 combines design expertise with state-of-the-art
manufacturing technology to produce an extremely compact
and economical isolator whose performance and abundant user
features far exceed those offered in more expensive devices.
The AD210 provides a complete isolation function with both
signal and power isolation supplied via transformer coupling in-
ternal to the module. The AD210’s functionally complete de-
sign, powered by a single +15V supply, eliminates the need for
an external DC/DC converter, unlike optically coupled isolation
devices. The true three-port design structure permits the
AD210 to be applied as an input or output isolator, in single or
multichannel applications. The AD210 will maintain its high
performance under sustained common-mode stress.
Providing high accuracy and complete galvanic isolation, the
AD210 interrupts ground loops and leakage paths, and rejects
common-mode voltage and noise that may other vise degrade
measurement accuracy. In addition, the AD210 provides pro-
tection from fault conditions that may cause damage to other
sections of a measurement system.
PRODUCT HIGHLIGHTSThe AD210 is a full-featured isolator providing numerous user
benefits including:
High Common-Mode Performance: The AD210 provides2500V rms (Continuous) and ± 3500 V peak (Continuous) common-
mode voltage isolation between any two ports. Low input
capacitance of 5 pF results in a 120 dB CMR at a gain of 100,
and a low leakage current (2 μA rms max @ 240 V rms, 60 Hz).
High Accuracy: With maximum nonlinearity of ±0.012% (BGrade), gain drift of ±25 ppm/°C max and input offset drift of
(±10 ±30/G) μV/°C, the AD210 assures signal integrity while
providing high level isolation.
Wide Bandwidth: The AD210’s full-power bandwidth ofkHz makes it useful for wideband signals. It is also effective
in applications like control loops, where limited bandwidth
could result in instability.
Small Size: The AD210 provides a complete isolation functionin a small DIP package just 1.00" × 2.10" × 0.350". The low
profile DIP package allows application in 0.5" card racks and
assemblies. The pinout is optimized to facilitate board layout
while maintaining isolation spacing between ports.
Three-Port Design: The AD210’s three-port design structureallows each port (Input, Output, and Power) to remain inde-
pendent. This three-port design permits the AD210 to be used
as an input or output isolator. It also provides additional system
protection should a fault occur in the power source.
Isolated Power: ±15 V @ 5 mA is available at the input andoutput sections of the isolator. This feature permits the AD210
to excite floating signal conditioners, front-end amplifiers and
remote transducers at the input as well as other circuitry at the
output.
Flexible Input: An uncommitted operational amplifier is pro-vided at the input. This amplifier provides buffering and gain as
required and facilitates many alternative input functions as
required by the user.
*Covered by U.S. Patent No. 4,703,283.
AD210 PIN DESIGNATIONS
AD210–SPECIFICATIONS(typical @ +258C, and VS = +15V unless otherwise noted)NOTES
*Specifications same as AD210AN.
1Nonlinearity is specified as a % deviation from a best straight line..RTI – Referred to Input.
OUTLINE DIMENSIONSDimensions shown in inches and (mm).
AC1059 MATING SOCKET
INSIDE THE AD210The AD210 basic block diagram is illustrated in Figure 1.
A +15 V supply is connected to the power port, and15V isolated power is supplied to both the input and
output ports via a 50kHz carrier frequency. The uncom-
mitted input amplifier can be used to supply gain or buff-
ering of input signals to the AD210. The fullwave
modulator translates the signal to the carrier frequency for
application to transformer T1. The synchronous demodu-
lator in the output port reconstructs the input signal. AkHz, three-pole filter is employed to minimize output
noise and ripple. Finally, an output buffer provides a low
impedance output capable of driving a 2kΩ load.
29
OCOM
+VOSS
–VOSS
PWR COMPWR
–VISS
+VISS
ICOM
+IN
–INFigure 1.AD210 Block Diagram
USING THE AD210The AD210 is very simple to apply in a wide range of ap-
plications. Powered by a single +15V power supply, the
AD210 will provide outstanding performance when used
as an input or output isolator, in single and multichannel
configurations.
Input Configurations: The basic unity gain configura-tion for signals up to ±10V is shown in Figure 2. Addi-
tional input amplifier variations are shown in the following
figures. For smaller signal levels Figure 3 shows how to
obtain gain while maintaining a very high input impedance.
VOUT29
VSIG±10V
+15VVOUTFigure 2.Basic Unity Gain Configuration
The high input impedance of the circuits in Figures 2 and
3 can be maintained in an inverting application. Since the
AD210 is a three-port isolator, either the input leads or
Figure 3.Input Configuration for G > 1
Figure 4 shows how to accommodate current inputs or sum cur-
rents or voltages. This circuit configuration can also be used for
signals greater than ±10V. For example, a ±100V input span
can be handled with RF = 20kΩ and RS1 = 200 kΩ.
Figure 4.Summing or Current Input Configuration
AdjustmentsWhen gain and offset adjustments are required, the actual cir-
cuit adjustment components will depend on the choice of input
configuration and whether the adjustments are to be made at
the isolator’s input or output. Adjustments on the output side
might be used when potentiometers on the input side would
represent a hazard due to the presence of high common-mode
voltage during adjustment. Offset adjustments are best done at
the input side, as it is better to null the offset ahead of the gain.
Figure 5 shows the input adjustment circuit for use when the in-
put amplifier is configured in the noninverting mode. This offset
adjustment circuit injects a small voltage in series with the
AD210low side of the signal source. This will not work if the source has
another current path to input common or if current flows in the
signal source LO lead. To minimize CMR degradation, keep the
resistor in series with the input LO below a few hundred ohms.
Figure 5 also shows the preferred gain adjustment circuit. The
circuit shows RF of 50kΩ, and will work for gains of ten or
greater. The adjustment becomes less effective at lower gains
(its effect is halved at G = 2) so that the pot will have to be a
larger fraction of the total RF at low gain. At G = 1 (follower)
the gain cannot be adjusted downward without compromising
input impedance; it is better to adjust gain at the signal source
or after the output.
Figure 6 shows the input adjustment circuit for use when the
input amplifier is configured in the inverting mode. The offset
adjustment nulls the voltage at the summing node. This is pref-
erable to current injection because it is less affected by subse-
quent gain adjustment. Gain adjustment is made in the feedback
and will work for gains from 1V/V to 100V/V.
29
+15V
VSIG
GAIN
50kΩFigure 6.Adjustments for Inverting Input
Figure 7 shows how offset adjustments can be made at the out-
put, by offsetting the floating output port. In this circuit, ±15V
would be supplied by a separate source. The AD210’s output
amplifier is fixed at unity, therefore, output gain must be made
in a subsequent stage.
29
+15V
+15V–15VFigure 7.Output-Side Offset Adjustment
PCB Layout for Multichannel Applications:The unique
pinout positioning minimizes board space constraints for multi-
channel applications. Figure 8 shows the recommended printed
CHANNEL INPUTS23
0.1"
GRID
CHANNEL OUTPUTS23Figure 8.PCB Layout for Multichannel Applications with
Gain
Synchronization:The AD210 is insensitive to the clock of an
adjacent unit, eliminating the need to synchronize the clocks.
However, in rare instances channel to channel pick-up may
occur if input signal wires are bundled together. If this happens,
shielded input cables are recommended.
PERFORMANCE CHARACTERISTICS
Common-Mode Rejection: Figure 9 shows the common-mode rejection of the AD210 versus frequency, gain and input
source resistance. For maximum common-mode rejection of
unwanted signals, keep the input source resistance low and care-
fully lay out the input, avoiding excessive stray capacitance at
the input terminals.
Figure 9.Common-Mode Rejection vs. Frequency
Figure 12.Gain Nonlinearity Error vs. Output
Figure 13.Gain Nonlinearity vs. Output Swing
Gain vs. Temperature:Figure 14 illustrates the AD210’s
gain vs. temperature performance. The gain versus temperature
performance illustrated is for an AD210 configured as a unity
gain amplifier.
Figure 14.Gain vs. Temperature
Phase Shift:Figure 10 illustrates the AD210’s low phase shift
and gain versus frequency. The AD210’s phase shift and wide
bandwidth performance make it well suited for applications like
power monitors and controls systems.
100100k10k1k10
FREQUENCY – Hz
PHASE SHIFT – Degrees
GAIN – dBFigure 10.Phase Shift and Gain vs. Frequency
Input Noise vs. Frequency:Voltage noise referred to the input
is dependent on gain and signal bandwidth. Figure 11 illustrates
the typical input noise in nV/√Hz of the AD210 for a frequency
range from 10 to 10kHz.
10010k1k10
FREQUENCY – Hz
NOISE – nV/Figure 11.Input Noise vs. Frequency
Gain Nonlinearity vs. Output:Gain nonlinearity is defined as the
deviation of the output voltage from the best straight line, and is
specified as % peak-to-peak of output span. The AD210B provides
guaranteed maximum nonlinearity of ±0.012% with an output span of
±10V. The AD210’s nonlinearity performance is shown in Figure 12.
Gain Nonlinearity vs. Output Swing:The gain nonlinearity
of the AD210 varies as a function of total signal swing. When
the output swing is less than 20 volts, the gain nonlinearity as a
fraction of signal swing improves. The shape of the nonlinearity
remains constant. Figure 13 shows the gain nonlinearity of the
AD210 as a function of total signal swing.
AD210
Isolated Power:The AD210 provides isolated power at the
input and output ports. This power is useful for various signal
conditioning tasks. Both ports are rated at a nominal ±15V atmA.
The load characteristics of the isolated power supplies are
shown in Figure 15. For example, when measuring the load
rejection of the input isolated supplies VISS, the load is placed
between +VISS and –VISS. The curves labeled VISS and VOSS are
the individual load rejection characteristics of the input and the
output supplies, respectively.
There is also some effect on either isolated supply when loading
the other supply. The curve labeled CROSSLOAD indicates the
sensitivity of either the input or output supplies as a function of
the load on the opposite supply.
CURRENT – mA
VOLTAGEFigure 15.Isolated Power Supplies vs. Load
Lastly, the curves labeled VOSS simultaneous and VISS simulta-
neous indicate the load characteristics of the isolated power sup-
plies when an equal load is placed on both supplies.
The AD210 provides short circuit protection for its isolated
power supplies. When either the input supplies or the output
supplies are shorted to input common or output common,
respectively, no damage will be incurred, even under continuous
application of the short. However, the AD210 may be damaged
if the input and output supplies are shorted simultaneously.
LOAD – mA
RIPPLE – mV p-p
234567The isolated power supplies exhibit some ripple which varies as
a function of load. Figure 16a shows this relationship. The
AD210 has internal bypass capacitance to reduce the ripple to a
point where performance is not affected, even under full load.
Since the internal circuitry is more sensitive to noise on the
negative supplies, these supplies have been filtered more heavily.
Should a specific application require more bypassing on the iso-
lated power supplies, there is no problem with adding external
capacitors. Figure 16b depicts supply ripple as a function of
external bypass capacitance under full load.
10mV
0.1µF
100mV
1mV
CAPACITANCE
RIPPLE – Peak-Peak Volts
1µF10µF100µFFigure 16b.Isolated Power Supply Ripple vs. Bypass
Capacitance (Volts p-p, 1MHz Bandwidth, 5 mA Load)
APPLICATIONS EXAMPLES
Noise Reduction in Data Acquisition Systems: Transformercoupled isolation amplifiers must have a carrier to pass both ac
and dc signals through their signal transformers. Therefore,
some carrier ripple is inevitably passed through to the isolator
output. As the bandwidth of the isolator is increased more of the
carrier signal will be present at the output. In most cases, the
ripple at the AD210’s output will be insignificant when com-
pared to the measured signal. However, in some applications,
particularly when a fast analog-to-digital converter is used fol-
lowing the isolator, it may be desirable to add filtering; other-
wise ripple may cause inaccurate measurements. Figure 17
shows a circuit that will limit the isolator’s bandwidth, thereby
reducing the carrier ripple.
Figure 17.2-Pole, Output Filter
