Version: *B
Question:
What are the differences between the HX3 Rev. *A silicon and the HX3 Rev. *D silicon?
Answer:
The differences between the HX3 Rev. *A silicon and the HX3 Rev. *D silicon are shown in Table 1.
Table 1. Differences Between the HX3 Rev. *A Silicon and the HX3 Rev. *D Silicon
| Items | HX3 Rev. *A Silicon | HX3 Rev. *D Silicon |
| USB-IF Compliance | Requires Firmware on External EEPROM | No External EEPROM Required |
| FS-only Hub or Host Connected to HX3 Upstream Port | Not Supported | Supported |
| Suspend Power | 90 mW | 37.8 mW |
Question 2: Is the HX3 Rev. *D silicon USB-IF certified?
Answer: Yes, the HX3 Rev. *D silicon is USB-IF certified (TID# 330000060).
Question 3: Which HX3 parts have transitioned to the Rev. *D silicon?
Answer: All the HX3 parts currently available for order are based on the Rev. *D silicon. The following HX3 part numbers have been migrated from HX3 Rev. *A silicon to HX3 Rev. *D silicon.
- CYUSB3302
- CYUSB3304
- CYUSB3312
- CYUSB3314
- CYUSB3326
- CYUSB3328
- CYUSB2302
- CYUSB2304
Question 4: Is there a way to differentiate between parts with the HX3 Rev. *A and HX3 Rev. *D silicon.
Answer: Yes. Markings on ROW 3 of the HX3 package differentiate the Rev. *D silicon from the Rev. *A silicon, as shown in Figure 1. Cypress maintains traceability of the product to the wafer level, including wafer fabrication location, through the lot number marked on the package.
Figure 1. HX3 Rev. *A and Rev. *D Markings
Question 5: What is the impact of the HX3 Rev. *D silicon migration for customers who have designed using the HX3 Rev. *A silicon?
Answer:
- This silicon will be drop-in compatible for all part numbers. There is no need to change the board design or layout to use the HX3 Rev. *D silicon. Products manufactured are completely compatible with existing products from a functional, parametric, and quality performance perspective.
- Since the HX3 Rev. *D silicon passes USB-IF compliance (TID# 330000060) with internal ROM firmware, customers can save BOM by eliminating the EEPROM. In order to use internal ROM, the MOD_SEL pins need to be set to ‘1-1’. Please refer to Table 4: HX3 Boot Sequence of HX3 Datasheet.
- The HX3 Rev. *D silicon continues to support external EEPROM. If you use an external EEPROM with the HX3 Rev. *D silicon, you must use the Cypress-provided Version B7 firmware available from www.cypress.com/hx3. The MODE_SEL pins need to be set to ‘0-1’. Please refer to Table 4: HX3 Boot Sequence of HX3 Datasheet.
- If there is no valid firmware or configuration settings loaded on the EEPROM with the MODE_SEL pins set to ‘0-1’, then the HX3 enumerates in the vendor specific mode and will not function as a HUB.
- Older versions of firmware (for example, Version A9 and Version B3) are not supported in the HX3 Rev. *D silicon.
Question 6: When is the HX3 Rev. *D silicon being rollout out?
Answer: All HX3 customer shipments now are Rev *D silicon. Older version silicon (for example, Rev *A) is no longer shipped now.
Question 7: Can you still order the HX3 Rev. *A silicon?
Answer: No, the HX3 Rev. *A silicon is no longer available.
Question 8: What is the advantage of the HX3 Rev. *D silicon when you use an external EEPROM for configurations, such as custom VID/PID?
Answer: Using the HX3 Rev. *D silicon results in BOM cost reduction. The HX3 Rev. *D silicon requires a 2 Kb EEPROM (part number ST24LC02B) for storing custom configuration settings. The HX3 Rev. *A silicon requires a 16Kb EEPROM (part number ST24LC128) because it also has to store the boot firmware to pass USB-IF compliance.