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I am looking at LM6132 specifically. In the datasheet, the absolute maximum "Current at Output Pin" is +-25mA. Yet Digikey lists it's "Current - Output / Channel" as 4mA...

I assume digikey's value is the "recommended" output current.

The amp will be running off a +-12v power supply and unfortunately, in the section for 24v Vcc, the datasheet has no output current figure...

I am just curious as to what impacts I can expect with regard to life expectancy, if any, running the op amp at 10mA roughly 50% of it's life. That is, the opamp will likely be sourcing 10mA half the time it is powered on and 0mA the rest of the time.

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    \$\begingroup\$ Don't assume that Digikey's values mean anything at all. The datasheet is the only source for information that you can trust. \$\endgroup\$ Jan 17, 2020 at 0:16
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    \$\begingroup\$ Digikey just draws the values from the datasheets and sometimes they are misclassified or just wrong. \$\endgroup\$
    – DKNguyen
    Jan 17, 2020 at 0:26
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    \$\begingroup\$ Datasheet figs 17 18 19 20 21 tell you Isink and Isource change little with Vcc and are HIGHER at Vs = 3V than at 5V or 10V. \$\endgroup\$
    – Russell McMahon
    Jan 17, 2020 at 1:31
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    \$\begingroup\$ The device is not capable of sourcing (or sinking) 10mA (see figures 17 to 22 in the datasheet). You need to find an amplifier designed for high output current drive. \$\endgroup\$ Jan 17, 2020 at 9:37
  • \$\begingroup\$ As an alternative to finding a device designed for higher output currents, you could add outboard current boost circuitry, ti.com/lit/an/snoa600b/snoa600b.pdf \$\endgroup\$ Jan 17, 2020 at 10:41

3 Answers 3

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Absolute maximum is the minimum of what might be expected to damage a device.

Recommended operation conditions is when the device will work as specified.

In between, the device might not be damaged but it might not work as well as you expect it to (or might not work the way you expect it to which is considerably worse).

In your scenario example, excessive voltage output droop is to be expected, and probably other things like linearity, etc. Not to mention heat.

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I wouldn't expect the current drive capability to increase with supply voltage as usually the internals are driven from constant current sources.

According to the data sheet the part is not guaranteed to be able to drive more than a few mA (fig 18 & 20). I wouldn't expect the output to be able to drive the 10mA you indicate.

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4mA is the correct value based on a TYPICAL Output Isc Short Circuit Current test method. (actually 4mA sourcing , 3.5mA Sinking Typ)

Always abide by table values under Characteristics and stay well under Abs. Max.

However you should design for worst case of 1 mA or less load.

6.1 Absolute Maximum Ratings (Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.)

  • Current at Output Pin (3) ±25 mA
    • Continuous short circuit operation at elevated ambient temperature can result in exceeding the maximum allowed junction temperature of 150°C. (possible damage)
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