ZHCSQH7D November 2021 – April 2024 TUSB2E11
PRODUCTION DATA
The USB 2.0 specification does not specify high-speed output differential swing VOD during disconnect without external load. Only chirp level and the HS host disconnect threshold are specified. Specification implicitly assumes high-speed output differential swing VOD doubles during disconnect. However, the high-speed output differential swing during disconnect depends on the USB 2.0 TX output swing and pre-emphasis setting, as the common-mode voltage increase saturates the output swing level. If the output swing level is saturated, the VOD may not double.
The HS host disconnect threshold shall be adjusted to provide the most margin to avoid false disconnect as well as failure to detect a disconnect. See Table 8-2.
| USB HS TX Pre-Emphasis | ||||||
|---|---|---|---|---|---|---|
| USB HS TX Amplitude (Vp-p) | 0.5dB (0h) | 0.9dB (1h) | 1.2dB (2h) | 1.7dB (3h) | 2.1dB (4h) | 2.5dB (5h) |
| 740mV (0h ) | 545mV (1h) | 545mV (1h) | 545mV (1h) | 545mV (1h) | 545mV (1h) | 545mV (1h) |
| 760mV (1h ) | 565mV (2h) | 565mV (2h) | 565mV (2h) | 565mV (2h) | 565mV (2h) | 565mV (2h) |
| 780mV (2h ) | 585mV (3h) | 585mV (3h) | 585mV (3h) | 585mV (3h) | 585mV (3h) | 585mV (3h) |
| 800mV (3h ) | 585mV (3h) | 585mV (3h) | 585mV (3h) | 585mV (3h) | 585mV (3h) | 585mV (3h) |
| 820mV (4h ) | 605mV (4h) | 605mV (4h) | 605mV (4h) | 605mV (4h) | 605mV (4h) | 605mV (4h) |
| 840mV (5h ) | 625mV (5h) | 625mV (5h) | 625mV (5h) | 625mV (5h) | 625mV (5h) | 625mV (5h) |
| 860mV (6h ) | 645mV (6h) | 645mV (6h) | 645mV (6h) | 645mV (6h) | 625mV (5h) | 625mV (5h) |
| 880mV (7h ) | 645mV (6h) | 645mV (6h) | 645mV (6h) | 645mV (6h) | 645mV (6h) | 645mV (6h) |
| 900mV (8h ) | 665mV (7h) | 665mV (7h) | 665mV (7h) | 665mV (7h) | 665mV (7h) | 645mV (6h) |
| 920mV (9h ) | 685mV (8h) | 685mV (8h) | 685mV (8h) | 665mV (7h) | 665mV (7h) | 665mV (7h) |
| 940mV (Ah ) | 685mV (8h) | 685mV (8h) | 685mV (8h) | 685mV (8h) | 665mV (7h) | 665mV (7h) |
| 960mV (Bh ) | 705mV (9h) | 705mV (9h) | 705mV (9h) | 685mV (8h) | 685mV (8h) | 665mV (7h) |
| 980mV (Ch ) | 725mV (Ah) | 705mV (9h) | 705mV (9h) | 705mV (9h) | 685mV (8h) | 685mV (8h) |
| 1000mV (Dh ) | 725mV (Ah) | 725mV (Ah) | 705mV (9h) | 705mV (9h) | 685mV (8h) | 685mV (8h) |
| 1020mV (Eh ) | 725mV (Ah) | 725mV (Ah) | 725mV (Ah) | 705mV (9h) | 705mV (9h) | 685mV (8h) |
| 1040mV (Fh ) | 745mV (Bh) | 725mV (Ah) | 725mV (Ah) | 705mV (9h) | 705mV (9h) | 685mV (8h) |