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# LM224: Lm224 temp at 100°C

Part Number: LM224
Other Parts Discussed in Thread: TLV170, LM2902, TS321, , LM2902KAV

we want to use the LM224 at a Ta. of 100°C under following condition

3 OPAMP very low current

1 OPAMP only 5 MA sink

supply voltage 15V

can we use this part for Ta.=100°C?

is there other disadvantage at Ta.=100°C?

• Hi Otmar,

This part is not rated for 100°C ambient temperature, you can consult the recommended operating conditions table (6.3) to see this.

If you'd like a part that will be able to operate at 100°C, I would recommend the TLV170 - it's rated for 125°C operating. At higher temperatures, you'll have higher offset voltage and other parameters will shift as well.

-Paul
• Otmar,

LM2902 is rated for 125C.
Is there a special reason for wanting to use LM224?

Output dissipation is about 1V * 5mA = 5mW; Quiescent current dissipation 15V * 1.4mA = 21mW
Package type and board characteristics will affect final die temperature.

If you only need one amplifier, try TS321
• Dear TI

The given answers which I got do not satisfy me.

I want to use the LM224A because the offset voltages are lower than in LM2902 types. I need a quad Opamp.

Unfortunately my Ta is 100°C (15K higher than LM224A is rated).

Fortunately my power losses in the LM224A is lower than in the datasheet allowed: only 1 amplifier makes losses: Vout is 1V, Isink is 5mA, Vcc is 15V.
The other 3 amplifiers are used but the output current is < 1mA. --> intern losses very low.

question 1: how high is the allowed Tjunction max intern for the LM224A?

question 2:  how much intern losses are allowed @Ta 85°?

question 3: how much intern losses are allowed @Ta 100°?

question 4: how much intern losses are allowed @Ta 115°?

question 5: How do you calculate the intern losses? Vout is 1V, Isink is 5mA, Vcc is 15V.

Thanks in advance Dietmar Kiefer, Delta Energy Systems Teningen

• Dietmar,

LM2902KAV is the 125C low Vio version device in this product family.

Absolute maximum junction temperature is 150C; this temperature results in reduced expected lifetime.
Internal power loss is Vcc * Icc where Icc is the quiescent current that doesn't include load current.
Internal power loss from loads is (VOUT - GND) * IOUT when sinking current.
Internal power loss from loads is (VCC - VOUT) * IOUT when sourcing current.
Add up the three losses to get a total power loss.