signal input of LM358 can be negative?

kerb huang

Intellectual 690 points

Other Parts Discussed in Thread: LM358

Hello,

Can negative signal be connected to input pin of LM358? use dual supply (+/- 5V)

Thank you,

kerb

over 9 years ago

0 Ron Michallick over 9 years ago

TI__Guru**** 165316 points

Kerb,

If inputs can go below GND pin then a series resistance should be added to keep current less than 1mA.
Output may be incorrect when this input current flows.

While GND pin is -5V, input can be -5V also; that is fine.

0 kerb huang over 9 years ago in reply to Ron Michallick

Intellectual 690 points

thank you！

0 kerb huang over 9 years ago in reply to Ron Michallick

Intellectual 690 points

Hi Ronald,

what is the output range of LM358 when the supply is +/-5V ?

Best reagards,
Kerb

0 Ron Michallick over 9 years ago in reply to kerb huang

TI__Guru**** 165316 points

Kerb,

VOH is VCC - 1.5V for light loads. A little less for more load.
VOL is VCC- (GND) pin is close to VCC- for loads less than 12uA.
Above 50uA, the VOL is closer to VCC- + 0.8V

0 kerb huang over 9 years ago in reply to Ron Michallick

Intellectual 690 points

thank you very much for your support!!!

Amplifiers

Amplifiers forum

signal input of LM358 can be negative?