Avago Optocoupler HCPL-2202 Failure Analysis
Gideon Analytical Laboratories received several Avago HCPL-2202 Optocouplers for failure analysis. These optocouplers have a totem pole output stages and optical receiver input stages with built-in Schmitt triggers to provide logic-compatible waveforms. They feature low input current (1.6mA to 1.8mA), Mbd typical signal rate, and guaranteed performance from -40 to 85 degrees Celsius. Some of their applications include isolation of high-speed logic systems, microprocessor system interfaces, and ground loop elimination. Our goal was to determine why the Avago HCPL-2202 Octocouplers had been failing.
Once receiving the Avago HCPL-2202, we went right to work conducting failure analysis. None of the packages had any mechanical or thermal damage. All of the packages in addition to a new part was tested to ensure the failures and operation. All of the defective optocouplers were failed on the output side. The input diodes were tested with a curve tracer. The samples differed in their respective results. X-rays revealed no damage on any of the wire bonds on any sample. Sample 1 had thermal damage around the ground rail and transistor, along with thermal damage on several trace lines. Sample 2 was decapsulated, revealing a crack in the die near the ground pin. There was also evidence of electrical over stress (EOS). EOS results in locally increased temperatures can lead to immediate failure by melting or vaporizing metallization layers, melting the semiconductor or by changing structures. Sample 3 also had evidence of EOS, this time on the ground rail. All of these failures of the Avago HCPL-2202 optocouplers were related to excessive power usage.
Yet another problem solved by the problem solvers of the electronic industry. Whether the problem is large or small, whether your company is located in New York, Japan, or any other part of the inhabitable globe, Gideon Analytical Laboratories is the analytical laboratory choice for you. With decades of experience, a team of expert professionals, and high-tech analytical equipment, Gideon will not let you down. Have your problem solved by the experts. Call Gideon Analytical Laboratories today.
Sample 3 diode tested normal
Curve Trace sample 1
Sample 3, more EOS on the ground rail
X ray revealed no damage to wire bonds
Sample 1, input diode mounted directly over the optical receiver
Sample 1 micrograph, no damage
Sample 1, thermal damage on ground rail and transistor, in yellow ring
Color differences in the ground rail denotes thermal damage
More thermal damage to trace lines
Diode in sample 2
Sample 2, crack in the die near ground pin
Sample 2, close up of the crack near the ground