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SN74AVC4T245: Improve reliability by add resistance on control pin

Part Number: SN74AVC4T245
Other Parts Discussed in Thread: SN74S04, SN7404

Tool/software:

Hi,

I saw a statement on the document SDYA009C (Designing With Logic, a TI's document): 

" the inputs of these devices must be connected to the supply voltage VCC via series resistor RS. 

This resistor should be dimensioned such that the current flowing into the gate or gates, which results from overvoltage, does not exceed 1 mA."

I find the document is released on June 1997.

I want to know if all logic chips devices must follow this rule? Or which serieses must follow this rule?

Is there any update in the document or any manufacturing process improvement that the input pins and control pins of logic chips do not need to add resistor any more?

Thanks.

  • That sentence talks about old, bipolar devices with multi-emitter inputs (e.g., SN7404, SN74S04). For all other devices, see the previous paragraph:

    If a low level is required, the input should be directly connected to GND; if a high level is required, it should be connected with a voltage source corresponding with a high level. In general, this is the positive supply voltage VCC.