HCPL-7800A Avago Technologies US Inc., HCPL-7800A Datasheet - Page 13

• Manufacturer Part Number: HCPL-7800A
• Description: Optocoupler
• Manufacturer: Avago Technologies US Inc.

Specifications of HCPL-7800A

• No. Of Channels: 1
• Isolation Voltage: 3.75kV
• Optocoupler Output Type: Analog
• Input Current: 16mA
• Output Voltage: 3.8V
• Opto Case Style: DIP
• No. Of Pins: 8
• Peak Reflow Compatible (260 C): No
• Bandwidth: 100kHz
• Amplifier Type: Isolation
• Number Of Circuits: 1
• -3db Bandwidth: 100kHz
• Current - Input Bias: 500nA
• Voltage - Input Offset: 300µV
• Current - Supply: 10.9mA
• Current - Output / Channel: 16mA
• Voltage - Supply, Single/dual (±): 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 8-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Output Type: -
• Slew Rate: -
• Gain Bandwidth Product: -
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant, Contains lead / RoHS non-compliant
• Other names: 516-1141-5

Application Information
Power Supplies and Bypassing
The recommended supply con-nections are shown in
Figure 17. A floating power supply (which in many ap-
plications could be the same supply that is used to drive
the high-side power transistor) is regulated to 5 V using
a simple zener diode (D1); the value of resistor R4 should
be chosen to supply sufficient current from the existing
floating supply. The voltage from the current sensing
resistor (Rsense) is applied to the input of the HCPL-
7800(A) through an RC anti-aliasing filter (R2 and C2).
Although the application circuit is relatively simple, a few
recommendations should be followed to ensure optimal
performance.

* * *
Figure 17. Recommended Supply and Sense Resistor Connections.
MOTOR
+
R
SENSE
R1
-
HV+
HV-
* * *
GATE DRIVE
39 Ω
R2
CIRCUIT
5.1 V
D1
* * *
C1
0.1 µF
C2
0.01 µF
+
-
The power supply for the HCPL -7800(A) is most often
obtained from the same supply used to power the
power transistor gate drive circuit. If a dedicated supply
is required, in many cases it is possible to add an ad-
ditional winding on an existing transformer. Otherwise,
some sort of simple isolated supply can be used, such as
a line powered transformer or a high-frequency DC-DC
converter.
An inexpensive 78L05 three-terminal regulator can also
be used to reduce the floating supply voltage to 5 V. To
help attenuate high-frequency power supply noise or
ripple, a resistor or inductor can be used in series with
the input of the regulator to form a low-pass filter with
the regulator’s input bypass capacitor.
FLOATING
SUPPLY
POWER
HCPL-7800