GL850 datasheet(20/40 Pages) ETC

20 / 40 page

GL850 USB 2.0 4-Port HUB Controller

Page 20

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2.7 μs

Internal reset

External reset

Power good voltage, 2.5~2.8V

VCC(3.3V)

Figure 5.4 - Power on sequence of GL850

5.2.2 PGANG/SUSPND Setting

To save pin count, GL850 uses the same pin to decide individual/gang mode as well as to output the

suspend flag. The individual/gang mode is decided in the period of 1ms after power on reset. After that

period of time, this pin is changed to output mode. GL850 outputs the suspend flag once it is globally

suspended. For individual mode, a pull low resister greater than 100KΩ should be placed. For gang mode,

a pull high resister greater than 100KΩ should be placed. In figure 5.6, we also depict the suspend LED

indicator schematics. It should be noticed that the polarity of LED must be followed, otherwise the suspend

current will be over than the current limitation (2.5mA).

RESET#

GANG_CTL

1 ms

Input mode, strapping

to decide individual or

gang mode

Output mode, indicating

GL850 is in normal

mode or suspend mode

Figure 5.5 - Timing of PGANG/SUSPND strapping

GL850 Datasheet(PDF) 20 Page - List of Unclassifed Manufacturers