LMC7221: output FET

Hanno Reimer

Intellectual 1510 points

Part Number: LMC7221
Other Parts Discussed in Thread: TLV7022, TLV9032, LM393LV, TLV1805, TLV9022

Could you please tell us if the output FET in the LMC7221 is a self-locking type?

over 3 years ago

0 Paul Grohe over 3 years ago

TI__Mastermind 49906 points

Hello Hanno,

We are not sure what you mean by "self locking"?

Do you mean "latching"? If so - no, it is not a latching output.

Are you asking about start-up behavior? The LMC7221 does not have a specified start-up behavior. The output is expected to be "high-Z" during start-up, but there is a possibility of output "glitches" during initial start-up when below minimum supply voltage.

0 Hanno Reimer over 3 years ago in reply to Paul Grohe

TI__Intellectual 1510 points

sorry, what I meant was, is the out transistor an enhancement mosfet?

0 Joe Vanacore over 3 years ago in reply to Hanno Reimer

TI__Genius 10485 points

Hello Hanno,

We are looking into an answer to your question and will get back to you by the end of business tomorrow, 12/2.

Regards,

Joe

0 Paul Grohe over 3 years ago in reply to Hanno Reimer

TI__Mastermind 49906 points

Hello Hanno,

This is somewhat an unusual question.... Normally we do not discuss the "internals" of our devices, as that is considered proprietary information.

Most likely it is an enhancement MOSFET. Otherwise it would be conducting when the power is off (Vgs=0), which could cause problems for wired-OR bus configurations.

If you were relying on the output type to provide some sort of known start-up, we do have devices with POR for known start-up conditions, such as the TLV7022, TLV1805, TLV9022, TLV9032 and LM393LV families. That would be preferable than relying on an unspecified "side-feature" of a device.

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LMC7221: output FET