USB2642 datasheet(33/56 Pages) MICROCHIP

33 / 56 page

 2014-2015 Microchip Technology Inc.

DS00001578C-page 33

USB2642

7.4.3.22

ECh: Hub Controller Max Current For Self-Powered Operation

7.4.3.23

EDh: Hub Controller Max Current For Bus-Powered Operation

7.4.3.24

EEh: Power-On Time

7.4.3.25

EFh: Boost_Up

Bit

Name

Description

7:0

HC_MAX_C_SP

Value in 2 mA increments that the hub consumes from an upstream port

(VBUS) when operating as a self-powered hub. This value includes the hub

silicon along with the combined power consumption (from VBUS) of all

associated circuitry on the board. This value does NOT include the power

consumption of a permanently attached peripheral if the hub is configured

as a compound device.

Note:

The USB 2.0 Specification (References) does not permit this value

to exceed 100 mA.

A value of 50 (decimal) indicates 100 mA, which is the default value.

Bit

Name

Description

7:0

HC_MAX_C_BP

Value in 2 mA increments that the hub consumes from an upstream port

(VBUS) when operating as a bus-powered hub. This value will include the

hub silicon along with the combined power consumption (from VBUS) of all

associated circuitry on the board. This value will NOT include the power

consumption of a permanently attached peripheral if the hub is configured

as a compound device.

A value of 50 (decimal) would indicate 100 mA, which is the default value.

Bit

Name

Description

7:0

POWER_ON_TIME

The length of time that it takes (in 2 ms intervals) from the time the host

initiated power-on sequence begins on a port until power is adequate on that

port. If the host requests the power-on time, the system software uses this

value to determine how long to wait before accessing a powered-on port.

Bit

Name

Description

7:2

rsvd

1:0

BOOST_IOUT

USB electrical signaling drive strength boost bit for the upstream port ‘A’.

: normal electrical drive strength = no boost

: elevated electrical drive strength = low (approximately 4% boost)

: elevated electrical drive strength = medium (approximately 8% boost)

: elevated electrical drive strength = high (approximately 12% boost)

Note:

“Boost” could result in non-USB Compliant parameters. OEM

should use a 00 value unless specific implementation issues

require additional signal boosting to correct for degraded USB

signaling levels.

USB2642 Datasheet(PDF) 33 Page - Microchip Technology

USB2642 Datasheet(HTML) 33 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

Datasheet Download

Link URL