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DFT Tips for implementing Boundary Scan in your design.
1) Simple rule - provide Boundary Scan control (master) to I2C device signal pins. Provide boundary
scan control to both SDA and SCL. WP (Write Protect) is not a required scan access signal but must
be terminated or scan controlled so that Writes may happen.
2) If you are a seasoned or senior boundary scan test engineer, you may consider writing your own
I2C protocol code so that you can read internal registers out of I2C devices. This could increase your
test coverage if you were to start reading out I2C device registers for temperature devices, voltage
monitoring devices, current monitoring devices or even fan monitoring and control devices. You
could even program the monitor trip points within some of these devices if Boundary Scan access is
provided to SDA, SCL and WP is set to allow writes.
3) Provide full boundary scan access and control to all signals on I2C multiplexing devices. This will
allow you to test through these multiplexers, increasing your test coverage.
scan control to both SDA and SCL. WP (Write Protect) is not a required scan access signal but must
be terminated or scan controlled so that Writes may happen.
2) If you are a seasoned or senior boundary scan test engineer, you may consider writing your own
I2C protocol code so that you can read internal registers out of I2C devices. This could increase your
test coverage if you were to start reading out I2C device registers for temperature devices, voltage
monitoring devices, current monitoring devices or even fan monitoring and control devices. You
could even program the monitor trip points within some of these devices if Boundary Scan access is
provided to SDA, SCL and WP is set to allow writes.
3) Provide full boundary scan access and control to all signals on I2C multiplexing devices. This will
allow you to test through these multiplexers, increasing your test coverage.
DFT Tips - I2C testing
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