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DS26LS32MQML: Voh as a function of output current

Part Number: DS26LS32MQML
Other Parts Discussed in Thread: AM26LS32A

Hello,

The Voh_min specified in the current datasheet (SNOSAM6B) is equal to 2.5V for an output current of 440 uA with a supply voltage (Vcc) of 4.5V.

The first revision of the datasheet (from National Semiconductor) specified a typical Voh of 4.2V in the same conditions (Iout = 440 uA / Vcc = 4.5V) which is no more available in the current revision of the datasheet.

I have an application using the DS26LS32M where the output current is fairly higher than 440 uA and the nominal supply voltage is rather close to 5V.

In addition, the difference between the min (2.5V) and typ (4.2V) implies a significant spread (manufacturing process? Temperature? Other?) which has a significant impact on the circuit sizing. 

In order to be able to properly size the circuit in my application, I need curves of Voh = f(Ioh) under min/typ/max supply voltage conditions as can be found for instance in the AM26LS32A datasheet (SLLS115F, Figure 1). Are those data available from TI and can you please share them with me?

Kind regards,

Nicolas

  • Hi Nicolas,

    These curves do not exist for this datasheet - especially on parts > 10 years old there is generally less datasheet graphs and information that what we provide on newer devices unfortunately. Some datasheets do include this information from this period but it wasn't as consistent as it is on newer devices. 

    What I can say is that the AM26LS32A and the DS26LS32M are going to have very similar VOH curves - they have the same test conditions and results for the specs  - and as the naming suggests they are related in their design (not 1 to 1 but have a lot of similarities). The typical value is still probably hanging around the 4.2V - the biggest factor that is causing the huge sweep is mainly driven by temperature (things like process can have some tolerance - but the largest factor should be temp) where high temperature operation increases the output impedance - also even at high temp min values are not super likely as its essentially the bound. 

    Please let me know if there are any  other questions and I will see what I can do!

    Best,

    Parker Dodson