gl850 ETC-unknow, gl850 Datasheet - Page 20

• Manufacturer Part Number: gl850
• Description: Usb 2.0 4-port Hub Controller
• Manufacturer: ETC-unknow

5.2.2 PGANG/SUSPND Setting
©2000-2003 Genesys Logic Inc.—All rights reserved.
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 100Kè should be placed. For gang mode,
a pull high resister greater than 100Kè 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).
Internal reset
External reset
GANG_CTL
RESET#
Input mode, strapping
to decide individual or
gang mode
Figure 5.5 - Timing of PGANG/SUSPND strapping
Figure 5.4 - Power on sequence of GL850
2.7 ôs
Power good voltage, 2.5~2.8V
1 ms
Output mode, indicating
GL850 is in normal
mode or suspend mode
GL850 USB 2.0 4-Port HUB Controller
VCC(3.3V)
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