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HCPL-7800A/HCPL-7800
Isolation Amplifer
Datasheet
Description
The HCPL-7800(A) isolation amplier family was designed
for current sensing in electronic motor drives. In a typical
implementation, motor currents ow through an external
resistor and the resulting analog voltage drop is sensed
by the HCPL-7800(A). A dierential output voltage is
created on the other side of the HCPL-7800(A) optical
isolation barrier. This dierential output voltage is pro-
portional to the motor current and can be converted to
a single-ended signal by using an op-amp as shown in
the recommended application circuit. Since common-
mode voltage swings of several hundred volts in tens of
nanoseconds are common in modern switching inverter
motor drives, the HCPL-7800(A) was designed to ignore
very high common-mode transient slew rates (of at least
10 kV/µs).
The high CMR capability of the HCPL-7800(A) isolation
amplier provides the precision and stability needed to
accurately monitor motor current in high noise motor
control environ-ments, providing for smoother control
(less “torque ripple”) in various types of motor control
applications.
The product can also be used for general analog signal
isolation applications requiring high accuracy, stability,
and linearity under similarly severe noise con-ditions.
For general applications, we recommend the HCPL-7800
(gain tolerance of ±3%). For precision applications Avago
Technologies oers the HCPL-7800A with part-to-part
gain tolerance of ±1%. The HCPL-7800(A) utilizes sigma
delta (Σ−∆) analog-to-digital converter technology,
chopper stabilized ampliers, and a fully dierential
circuit topology.
Together, these features deliver unequaled isolation-
mode noise rejection, as well as excellent oset and
gain accuracy and stability over time and temperature.
This performance is delivered in a compact, auto-insert-
able, industry standard 8-pin DIP package that meets
worldwide regulatory safety standards. (A gull-wing
surface mount option #300 is also available).
Features
• 15 kV/µs Common-Mode Rejection at V
CM
= 1000 V
• Compact, Auto-Insertable Standard 8-pin DIP Pack-
age
• 0.00025 V/V/°C Gain Drift vs. Temperature
• 0.3 mV Input Oset Voltage
• 100 kHz Bandwidth
• 0.004% Nonlinearity
• Worldwide Safety Approval: UL 1577 (3750 Vrms/1 min.)
and CSA, IEC/EN/DIN EN 60747-5-2
• Advanced Sigma-Delta (Σ−∆) A/D Converter Technol-
ogy
• Fully Dierential Circuit Topology
Applications
• Motor Phase and Rail Current Sensing
• Inverter Current Sensing
• Switched Mode Power Supply Signal Isolation
• General Purpose Current Sensing and Monitoring
• General Purpose Analog Signal Isolation
Functional Diagram
1
2
3
4
8
7
6
5
I
DD1
V
DD1
V
IN+
V
IN-
GND1
I
DD2
V
DD2
V
OUT+
V
OUT-
GND2
+
-
+
-
SHIELD
CAUTION: It is advised that normal static precautions be taken in handling and assembly
of this component to prevent damage and /or degradation which may be induced by ESD.
Lead (Pb) Free
RoHS 6 fully
compliant
RoHS 6 fully compliant options available;
-xxxE denotes a lead-free product
NOTE: A 0.1 μF bypass capacitor must be connected
between pins 1 and 4 and between pins 5 and 8.
