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LM2901: LM2901 Data Sheet. It appears to me these two data statements are conflicting?

Byron Taradena
Prodigy 40 points
Part Number: LM2901

I need help understanding LM2901 Data Sheet. It appears to me these two data sheet statements are conflicting statement?

I must be messing something?

Byron in Tucson AZ.

8.3 Feature Description
LMx39 consists of a PNP Darlington pair input, allowing the device to operate with very high gain and fast response with minimal input bias current. The input Darlington pair creates a limit on the input common-mode voltage capability, allowing LMx39 to accurately function from ground to (VCC – 1.5 V) differential input. This isenables much head room for modern day supplies of 3.3 V and 5 V.
The output consists of an open-drain NPN (pulldown or low-side) transistor. The output NPN sinks current when the positive input voltage is higher than the negative input voltage and the offset voltage.
The VOL is resistive and scales with the output current. See the Specifications section for VOL values with respect to the output current.

9.2.2.1 Input Voltage Range
When choosing the input voltage range, the input common-mode voltage range (VICR) must be taken in to account. If temperature operation is above or below 25°C the VICR can range from 0 V to VCC– 2 V. This limits the input voltage range to as high as VCC– 2 V and as low as 0 V. Operation outside of this range can yield incorrect comparisons.
The following list describes the outcomes of some input voltage situations.
• When both IN– and IN+ are both within the common-mode range:
– If IN– is higher than IN+ and the offset voltage, the output is low and the output transistor is sinking current
– If IN– is lower than IN+ and the offset voltage, the output is high impedance and the output transistor is not conducting
• When IN– is higher than common mode and IN+ is within common mode, the output is low and the output transistor is sinking current
• When IN+ is higher than common mode and IN– is within common mode, the output is high impedance and the output transistor is not conducting
• When IN– and IN+ are both higher than common mode, the output is low and the output transistor is sinking current

  • 0
    TI__Guru 61046 points
    Hello Byron,

    The datasheet is in the process of being updated. Some administrative issues are currently keeping it from being released - but it will be updated.

    The section 8.3 text is backwards. The output will sink current (goes low) when the inverting input (IN-) is higher than the non-inverting input (IN+).

    The 9.2.2.1 text is correct.