ACPL-C79B, ACPL-C79A, ACPL-C790
Precision Miniature Isolation Ampliers
Data Sheet
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.
Description
The ACPL-C79B/C79A/C790 isolation ampliers are
designed for current and voltage sensing in electronic
power converters in applications including motor drives
and renewable energy systems. In a typical motor drive
implementation, current ows through an external
resistor and the resulting analog voltage drop is sensed by
the isolation amplier. A dierential output voltage that is
proportional to the current is created on the other side of
the optical isolation barrier.
For general applications, the ACPL-C79A (±1% gain
tolerance) and the ACPL-C790 (±3% gain tolerance)
are recommended. For high precision applications, the
ACPL-C79B (±0.5% gain tolerance) can be used. The
product operates from a single 5 V supply and provides
excellent linearity and dynamic performance of 62 dB SNR.
With 200 kHz bandwidth, 1.6 µs fast response time, the
product captures transients in short circuit and overload
conditions. The high common-mode transient immunity
(15 kV/µs) of the ACPL-C79B/C79A/C790 provides the
precision and stability needed to accurately monitor
motor current in high noise motor control environments,
providing for smoother control (less “torque ripple”) in
various types of motor control applications.
Combined with superior optical coupling technology, the
ACPL-C79B/C79A/C790 implements sigma-delta (∑-∆)
analog-to-digital converter, chopper stabilized ampli-
ers, and a fully dierential circuit topology to provide
unequaled isolation-mode noise rejection, low oset,
high gain accuracy and stability. This performance is
delivered in a compact, auto-insertable Stretched SO-8
(SSO-8) package that meets worldwide regulatory safety
standards.
Functional Diagram
Features
• ±0.5% High Gain Accuracy (ACPL-C79B)
• –50 ppm/°C Low Gain Drift
• 0.4 mV Input Oset Voltage
• 0.05% Excellent Linearity
• 62 dB SNR
• 200 kHz Wide Bandwidth
• 3 V to 5.5 V Wide Supply Range for Output Side
• –40°C to +105°C Operating Temperature Range
• Advanced Sigma-Delta (∑-∆) A/D Converter Technology
• Fully Dierential Isolation Amplier
• 15 kV/µs Common-Mode Transient Immunity
• Compact, Auto-Insertable Stretched SO-8 Package
• Safety and Regulatory Approvals:
– IEC/EN/DIN EN 60747-5-5: 1414 Vpeak working
insulation voltage
– UL 1577: 5000 Vrms/1min double protection rating
– CSA: Component Acceptance Notice #5
Applications
• Current/Voltage Sensing in AC and Servo Motor Drives
• Solar Inverters, Wind Turbine Inverters
• Industrial Process Control
• Data acquisition systems
• Switching Power Supply Signal Isolation
• General Purpose Analog Signal Isolation
• Traditional Current Transducer Replacements
NOTE:
A 0.1 µF bypass capacitor must be connected
between pins 1 and 4 and between pins 5 and 8.
Figure 1.
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
