CM2031 Datasheet, PDF (16/18 Pages) California Micro Devices Corp – HDMI Receiver Port Protection and Interface Device

CM2031
Note: This circuitry is used only in the CM2021. Depopulate the components for CM2031 applications in a CM2021/ CM2031 dual
footprint layout.
6 _{Footprint compatibility - The CM2031 has (built-in) internal backdrive protection.}
The CM2021 does not not have internal backdrive protection and requires the external R_CEC and D_CEC components.
7 _{(For CM2031) If CEC firmware is not implemented, do not populate with 0Ω resistor. If CEC firmware is implemented, then}
populate with 0Ω resistor.
(For CM2021) Populate with 0Ω resistor in either case.
Application Information (cont’d)
Design Considerations
DUT On vs. DUT Off
Many HDMI CTS tests require a power off condition on the System Under Test. Many discrete ESD diode
configurations can be forward baised when their VDD rail is lower than the I/O pin bias, thereby exhibiting
extremely high apparent capacitance measurements, for example. The MediaGuard^ΤΜ backdrive isolation circuitry
limits this current to less than 5µA, and will help ensure HDMI compliance.
Please review all of the current HDMI design guidelines available at:
http://www.calmicro.com/applications/customer/downloads/current-cmd-mediaguard-design-guidelines.zip
Rev. 5 | Page 16 of 18 | www.onsemi.com