FAQs:  MAX3420E MAX3420E

General Questions

What is the MAX3420E?
Does the MAX3420E include a microprocessor?
What packages are available for the MAX3420E?

USB Questions

What USB speeds does the MAX3420E support?
Does the MAX3420E comply with the USB spec? Which revision?
How many endpoints does the MAX3420E support?
Why does the MAX3420E not support ISOCHRONOUS transfers?
Can I use the MAX3420E in a self-powered peripheral?
Can I use the MAX3420E in a bus-powered peripheral?
What external circuitry do I need to connect the MAX3420E to USB?
Can you recommend a 3.3V regulator?
What does the CONNECT bit do?

Interface Questions

How does a microprocessor connect to the MAX3420E?
You say the SPI interface is 3, 4, or 5 wires. What does this mean?
What SPI clocking modes does the MAX3420E support?
My CPU uses a 2.5V supply, but the MAX3420E uses a 3.3V VCC supply. Do I need external level translators?
What is the purpose of the MAX3420E INT pin?
Does the MAX3420E support active-low wired-OR interrupts? How about edge active interrupts?
How fast can I run the MAX3420E SPI interface (SCLK max frequency)?
Is there a low limit to the MAX3420E SCLK frequency?
I have an 8-pin microprocessor, and it takes 5 of its' IO pins to connect to the MAX3420E. How do I do IO?
Do I need to add external pullup resistors to the GPIN pins?
Can I drive optocouplers from the SPI interface pins?
What is the purpose of the VBCOMP pin? Does it power the MAX3420E?

Programming Questions

How does my firmware talk to the MAX3420E?
How do I program the MAX3420E to handle USB enumeration?
How do I program a BULK IN transfer?
What if a USB IN request comes in while firmware is loading the IN FIFO?
How do I know when to load an IN FIFO?
What if there is a USB transfer error? Do I need to write code to handle the error condition?
How do I program a BULK OUT transfer?
How about INTERRUPT transfers?
How do I program a SETUP transfer?
Do I need to program the USB data toggles?
The MAX3420E interrupt request bits are cleared by writing "1" to them. Is this backwards?
Do you have any programming tips?

Host Software Questions

How does my Windows® application talk to the MAX3420E?
What example code does Maxim supply?
I want to design a MAX3420E-based device that does not conform to a standard Windows class. What do I use for a Windows driver?
How does the MAX3420E compare with USB 'serial bridge' chips?
What are the advantages and disadvantages of the MAX3420E approach?

Miscellaneous Questions

Can my firmware determine which chip revision I have?
What is the current revision level of the MAX3420E?