Ampro Corporation 486E manual Power Sequencing, Advanced Power Management

Product Reference

Table 2–31. J3 Mating Connectors

Part Description	Mating Connector
Ribbon	3M 4325-7600
Discrete Wire	MOLEX Housing 55-22-2502
	PIN 16-02-0103

Power Sequencing

Some LCD panels can be damaged when the Vee bias supply is applied to the LCD substrate without first enabling the control and data lines. This can result in damage to the panel or reduction of its operational life. The video controller generates signals for sequencing the power in the proper order to protect the panel from these effects. If an external power supply is connected, special enabling signals ENVEE and ENVDD provided on the J3 connector must be used to enable this supply.

As an option, Ampro provides a Vee bias supply board that will interface to the Little Board/486e CPU through connector J4. This board contains circuitry to generate a Vee bias voltage that is already properly sequenced.

Advanced Power Management

The same signals that support power sequencing also provide for power management. On-board circuitry provides the following power management features in panel off mode:

!CRT - OFF

!FPD – OFF

!VGA subsystem registers and display memory - ON

In standby mode, the following occurs:

!CRT – OFF

!FPD Interface – OFF

!VGA Subsystem – OFF

!Screen DRAM – Low power mode (only DRAM is refreshed)

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