LPC47N227TQFP Standard Microsystems (SMSC), LPC47N227TQFP Datasheet - Page 186

• Manufacturer Part Number: LPC47N227TQFP
• Manufacturer: Standard Microsystems (SMSC)

Specifications of LPC47N227TQFP

• Lead Free Status / RoHS Status: Not Compliant

Output Drivers
To facilitate higher performance data transfer, the use of balanced CMOS active drivers for critical
signals (Data, HostAck, HostClk, PeriphAck, PeriphClk) are used in ECP Mode. Because the use of
active drivers can present compatibility problems in Compatible Mode (the control signals, by tradition,
are specified as open-collector), the drivers are dynamically changed from open-collector to
totem-pole. The timing for the dynamic driver change is specified in then IEEE 1284 Extended
Capabilities Port Protocol and ISA Interface Standard, Rev. 1.14, July 14, 1993, available from
Microsoft. The dynamic driver change must be implemented properly to prevent glitching the outputs.
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