Hi,
I have several questions relating to the TPD4S014 and its EVM on behalf of an engineer.
1.The TPD4S14EVM that was received upon EVM-order match the picture on the product page at TI.com. However, the EVM layout in the user's guide does not correspond to the actual board (earlier revision?). That means that the schematics, enumeration etc are incorrect. Do you have updated schematics for the TIDAP-19912-02?
2. In the datasheet (p.17, section 10.2) there are recommendations for the layout. What is not commented is the connection of ground to the USB contact. What's your advice? Do you recommend to place a cap or coil between the ground and shield in the USB-cable and the chassi on the card? In the EVM user's guide, the schematic depicts connection between earth on the USB bus (J2/3:5) directly to the chassi (pin 8,9), whereas there is a decoupling cap of 10uF between VBUS and the chassi (pin 6,7). Is this the recommended layout? It is hard to say how the design of the actual EVM looks like without the schematics and how it relates to the design rules in the datasheet.
3. In the schematics to the EVM user's guide, there are two kinds of ceramic capacitors (C1 and C2). One kind on one side of the PCB and another kind on the other side of the TPD4S014. Is there a reason behind this? In particular, why does the cap rated for a lower voltage (C1) face the outer world?
I appreciate your swift reply.
Thanks in advance,
Gustaf